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ksoggs
13th May 2006, 19:03
I have posted about this stuff before, but today i found new proof.
i was told check for intake gasket leaks at the y-pipes... so with bike warm and running i douced the gaskets with spray carb cleaner... bike didnt even notice... so i am ruling out the intake leak.

but what i did notice... I got ballsy and put my hand over the exhaust, (before it got too hot.) and when i pressed my hand firmly against the pipe of the good cylinder my fingers felt like they were on vibrate... poppoppoppoppoppoppop
then i moved my hand to the funky side... and i had my proof.
even with the bike warmed up and what i THOUGHT was running well...
popdunkdunkpopdunkdunkpopdunkdunkpop
it is like one cylinder is running full time, and the other is only really firing every other time...

so with intake leak out of the question, and this being only in one cylinder....

i have to assume that it isnt fuel related... it must be either mechanical (valves, lifters) or ignition... im not sure how these things spark, but is it possible something could only be triggering the spark 1 out of 2 times on the one cylinder?? are these things electronic ignition? or points? or what?

CBAS5
13th May 2006, 19:10
Harley engines do fire unevenly with the front cylinder being dominant as far as my non-technical mind knows. I could be wrong. So that may be what you are experiencing.

Some things you can do is:

1) Pull the plugs and see if they are about equal - would indicate both cylinders working properly
2) Pull the wire off the front spark plug and see if the engine will still run with only the rear cylinder - the idle will bog down significantly, but it should keep running.

Shu
13th May 2006, 19:36
How does the bike run?

With the upgrades you have listed about your bike it ought to run real hard.

Oh and those are Bassani pipes.

Now on to the problem.

I could be ignition related. Do you know what ignition you have in the bike? Is it stock or is it an aftermarket unit? Stock ignition in your bike was dual fire. If it is an aftermarket, is it single fire? For the dead miss to be so consistent, I would look at ignition.

ksoggs
13th May 2006, 19:42
Ignition is stock, as far as i know...

here is a video i took of the exhaust oddities...

check out my fancy tool... ya gotta love it.

www.scorpion3d.com/bike/exhaust1.avi

www.scorpion3d.com/bike/exhaust2.avi

they may take a minute to load, but you can hear and see for yourself what i am talking about.

CBAS5
13th May 2006, 20:03
Here is an article that you might find useful:

http://www.wildwestcycle.com/f_firing.html


Some excerpts:

The idle is an irregular, lumpy rumble; utterly unmistakable.

So here's the firing order.

Front Bang, rotate 315 degrees - Rear Bang, rotate 405 degrees - Front Bang, rotate 315 degrees, - Rear Bang, etc.
So there it is. The engine sounds like it does because the firing order is irregular, it kind of lopes along, as it has since 1903. And probably will until the next century, if the traditionalists have their way. I hope so.

Gone
13th May 2006, 20:13
Have you tried increasing the idle and adjusting the mixture screw? Lean cylinder would have nothing to fire.
Recently, did you change the jet(s)?
Recently, adjusted the float level?

My typical, out-of-the-box thinking.
Let us know how it goes.

Gone
13th May 2006, 20:20
Well, now that I watched your video, I think you need to do a compression check. The card being sucked back into the pipe acts like a burned exhaust valve or the exhaust valve is not closing completely. Hence, on the intake stroke, as the piston pulls air in through (normally) the intake valve, with an exhaust valve leaking, the air would be pulled in from the exhaust valve and pull your playing card toward the exhaust pipe.

DONNY
13th May 2006, 20:21
I'm pretty sure mine does the same thing. At an idle, the front cylinder has a steady pop-pop-pop-pop-pop, and the rear is more like pop----pop----pop-pop-pop----pop-----pop. I thought it was strange myself, but it runs too strong to be wrong, and also, my plugs look good on both cyls.

shotgun46
13th May 2006, 20:24
how does the bike run while riding ? the video sounds normal to me !

ted
13th May 2006, 20:26
Sounds like a Sportster idling. How is it running?
Ted

ksoggs
13th May 2006, 21:11
It seems to run just fine above idle, but before i learned the proper way to warm it up, i used way too much choke and fouled out a few plugs, and both times i changed them, the back cylinder was WAY blacker than the front. one time the front looked perfect, and the back looked all black and sooty.
the one time the plugs got fouled, it would backfire ALOT but only from the back cylinder.

I am aware that the cylinders don't run in opposition to eachother like most engines do... the fire one right after the other, then slient, silent, pop pop, silent silent pop pop. thus the cool harley sound. but mine runs more like silent silent pop pop silent silent pop cough silent silent pop pop silent silent pop cough. and i am no harley guru, but i doubt that is normal.

and then after feeling the exhaust i noticed a HUGE difference. the front cylinder is a steady rhythmic STRONG pop. like it litterally pushed my fingers away. the back cylinder was far weaker, hardly moved my fingers away, and as explained before, it was more like a <weak>pop then what felt like 2 very faint coughs, then another weak pop.

so to break it down in time....

(cycles) 1 2 3 4 5 6 7 8 9 10
front cyl POP POP POP
back cyl pop coughcough pop coughcough pop

that is my assumption as to what is going on inside.. based on sound and feel of the exhaust pressure.

my understanding is a harley should be closer to
(cycles) 1 2 3 4 5 6 7 8 9 10
front cyl POP POP POP
back cyl POP POP POP


I am hoping it isnt a valve, but based on my general (non-harley) mechaincal understanding, this is sounding like the most likely suspect...
that or ignition somehow skipping a cycle.

i cant see how it could be fuel or air, since they both use the same carb and intake... anything air or fuel related would equally effect both cylinders the same. So i am trying to figure out what else is cylinder dependant, as those are more likely suspects in my mind.

also, notice the jumping tach at idle.. that could be normal, i dont know... but seems rather jumpy to me.

ksoggs
13th May 2006, 21:14
someone do me a favor... if you have the true (seperate) dual exhausts, feel your exhaust, see if both pipes feel the same, or if yours too seem much more rhythmic and and stronger on one side than the other. let me know what you find.

Gone
13th May 2006, 21:27
Somewhere along the line, with the conversion and dual pipes, the carb. got rejetted. Have you tried to adjust the mixture and idle screws? Funny as it may seem, try it: you might like it.

ksoggs
13th May 2006, 21:45
Somewhere along the line, with the conversion and dual pipes, the carb. got rejetted. Have you tried to adjust the mixture and idle screws? Funny as it may seem, try it: you might like it.


here is a list of the performance stuff on my ride... and yes, one of them is the jets. .45 idle jets dealer installed and tuned.

i am willing to try anything. you think i am too rich or too lean?
(i just find it hard to understand how carb mixture can effect one cyl and not the other when they share the same carb and intake.)




Buell ThunderStom High Flow Heads
16797-98Y 16827-98YB

Buell 1200 Jug-piston Set

Force Winder Intake

Bassani ProStreet Slashcut Exhaust

Screamin-eagle Cam Kit

CV Carb.
.45 slow jet (27170-89)

CBAS5
13th May 2006, 21:51
i cant see how it could be fuel or air, since they both use the same carb and intake... anything air or fuel related would equally effect both cylinders the same.

I really don't know what i'm talking about, but since you fouled the rear plug could it be plug related? The rear spark plug not firing as well as the front spark plug?

ted
13th May 2006, 21:55
Your reasoning about the carb effecting both cylinders equally is a bit off. To put it simply, the uneven firing lets the airflow in the carb slow down during the longer lag in intake. Another thing is, cams with long overlap sometimes allow air to pass the jet in the carb an extra two times. Especially with individual free breathing pipes. If you have the aircleaner off, you might see a fog in the carb throat due to that. I see you have a Forcewinder too. Some of the earlier ones had a design glitch, something about a breather that needs to be modified??
Ted

Gone
13th May 2006, 22:01
I've been thinking about the valve thing; even the stock cams have some overlap. With overlap, the intake/exhaust valves do not completely close during portions of the ottocycle. The exhaust valve is open "some" during the intake stroke and helps inertia and cylinder fill; what the duration is, I don't know, but your SE cam kit with overlap makes sense now. (For your information, I'm not a Harley mechanic, but I've done some automotive work and am applying a lot of it to my sporty).

Anyway, adjust the idle screw to get about 1000 rpm; adjust the mixture screw in/out, see what the idle does and adjust to get a smooth idle. Before doing too much adjusting, it will help to turn the mixture screw in and "smoothly" seat the needle while counting how many turns out it was. I don't have the heads, compression, and pipes you do but my screw is out 3.5 turns with 9.5:1 compression, ported 883 heads, Ramflo ac, and stock pipes. 45/180 jets in the CV carb. You may need to go to a slightly larger idle jet; 48 maybe with your mods.

Not knowing the cams' duration, I expect it may be kind of "agressive" and the idle may not be smooth but I would think the exhaust pressure should be equal between the cylinders.

You say it runs fine, just doesn't idle smooth? Could be the cams agressive nature at idle and just needs mixture/idle adjustment.

MOREHP
13th May 2006, 22:06
someone do me a favor... if you have the true (seperate) dual exhausts, feel your exhaust, see if both pipes feel the same, or if yours too seem much more rhythmic and and stronger on one side than the other. let me know what you find.

I just checked mine both pipes firing with the same force both sounds the same. When I was tuning my engine I fouled a set of plugs and cleaned them up and reinstalled them. My idle sucked til I got a new set. Start with the easy stuff first my money is on the plugs. Good Luck!!!

ksoggs
13th May 2006, 22:34
plugs are a week old. i changed them right after learning how to properly warm up the bike. these plugs have stayed pretty good so far. they are just some $1.50 cheapys like autolite or champion. i didnt want to spend the money on a good set till i had everything tuned pretty well. I dont mind fouling out $3 in plugs, but would rather not do it to $15 plugs.

Ok, i am up for some experimentation. I would be thrilled if you guys are right and it is just an adjustment. And with that i am off to the garage.

sportynube, how hard was it to port your heads? or did you have them done? I am thinking about porting mine just for a lil better breathing.

Gone
13th May 2006, 22:40
NRHS is one of the forum sponsors. Here is their web link:
http://www.nrhsperformance.com/

I had mine done by Big Boyz Cycles; Bean called it a "street port."
http://www.bigboyzcycles.com/

Best of luck.

Shu
13th May 2006, 22:55
I agree, check the easy things first. Do a compression check on both cylinders. Do a leak down test on both as well. Those two test will identify if you have a valve or ring problem and also the condition of the engine/conversion. Next replace the spark plugs because they are cheap. Put in some Champions (local autoparts store for less than $3). Check the resistance of the plug wires. Check the connection (both ends) on the wires...push the plug boots up and check them good. Check the coil input wires and connection.

Then fire it up and TUNE your idle mixture (once FULLY warmed up). I am running a set of the SE cams and if the tach is bouncing more than 100 rpms at idle, then your idle mixture is off. If you do not get the idle mixture screw to affect the quality of idle, then I would pull the carb and take it apart and use a can of carb cleaner and clean every passage.

Also, what main jet do you have in it? With that combination, you should have had one listed on your parts list for the conversion. Most likely a 190 or so.

Have you checked the carb to intake seal?

ksoggs
14th May 2006, 01:11
I agree, check the easy things first. Do a compression check on both cylinders. Do a leak down test on both as well. Those two test will identify if you have a valve or ring problem and also the condition of the engine/conversion. Next replace the spark plugs because they are cheap. Put in some Champions (local autoparts store for less than $3). Check the resistance of the plug wires. Check the connection (both ends) on the wires...push the plug boots up and check them good. Check the coil input wires and connection.

i dont have a compression tester, or i would do that. Dont even know how to do a leak down test. Plugs are a week old, probably not even 100 miles on them. plug wired are good quality but are slightly old, i have thought about replacing them. I will have to check the wires carefully and the connections at the coil.


Then fire it up and TUNE your idle mixture (once FULLY warmed up). I am running a set of the SE cams and if the tach is bouncing more than 100 rpms at idle, then your idle mixture is off. If you do not get the idle mixture screw to affect the quality of idle, then I would pull the carb and take it apart and use a can of carb cleaner and clean every passage.

Also, what main jet do you have in it? With that combination, you should have had one listed on your parts list for the conversion. Most likely a 190 or so.

I did not see a main jet in the parts list for the conversion, this too i found odd. I will look closer, but i am fairly certain it isnt in there.

Have you checked the carb to intake seal?

If you are refering to the seal between the carb and y-pipe and between the y-pipe and cylinders, then yes... i had it running and hosed it down with a can of carb cleaner, and i didnt notice anything at all. so i assume those seals are good.
between the air cleaner and carb i didnt worry about as i didnt see how that could effect anything.

Shu
14th May 2006, 01:40
I may be worng, but I think AutoZone and several other autoparts stores have a loan a tool program (deposit required) and they might have a compression tester. Just a thought. Or I think they are only maybe $30
A leak down test is done with the compression tester guage. You pressurize the cylinders and then watch to see if it leaks down and how quickly.

I'd say it is an idle mixture problem though.

ksoggs
14th May 2006, 02:33
Interestingly.... as much work as had been done to this bike.... the mixture adjustment was still a virgin. all pluged up nice and pretty... My dremel made short work of that.

so i warmed the bike up... got it running about as good as could be expected... and then got twisting....

as i tightened things up a bit (closed the needle) it ran a little rougher, and sputtered and tried to die a few times... so i figured that wasnt the way i needed to go.

so i start to back the needle out, (open it up) and it came back to where it was... then a little more made it a tad bit better, and then nothing... nothing at all.. i almost backed it out till the needle fell out... nothing at all. it did get a faint hint better than before i started playing, but it stopped having any sort of effect right before i would have thought it would be good.
got me all excited... one way... oh that is bad, hmmm other way, oh wow, this is good, that is nice... ok maybe a lil more.... um.. ok maybe more... mooooooree... whats going on? mooooooooooooooorrrre... ok fine be that way!

so based on a little reading, i am guessing my jet is too small? And now i need to get to a harley shop and get the next largest jet?

and anyone care to tell me what a pain that well be to put in?

acording to the dealers paperwork, it is a .45 idle jet they put in... so what do you suggest? perhaps a .48? or a 50? i dunno, never jetted a harley before.

shotgun46
14th May 2006, 02:37
no shim the needle then see what happens !!

ksoggs
14th May 2006, 02:44
no shim the needle then see what happens !!

ok im a newbie... what does shimming do? and how does one do that?

shotgun46
14th May 2006, 03:12
makes you run a tad richer ! just a thought but give it a try !!

ksoggs
14th May 2006, 03:35
ok, is that something i can do on my own here with common household items? or will i need parts?

cuz i dont think many dealerships are open now... and if i have to wait to buy shims, why not just get a jet?

again i have no idea what a shim is, os the advantage of shimming over jetting, or any of that... but it would all be good to know before i go to the dealer tomorrow.

i did a search, but no where could i find an explaination of shimming the needle. lots of talk about it... but nothing saying what it is or what exactly it does, or why to do it and when.

shotgun46
14th May 2006, 03:39
http://members.aol.com/roundr1/CVK40.html look here down to the bottom it tells ya about the needle hope this helps !

Shu
14th May 2006, 03:39
At how many turns out on the mixture screw did it stop giving you better results? At how many turns out (turning in) did it start to stumble? You want to set your idle mixture screw between a lean stumble and a rich stumble. Also, do your adjustments in 1/4 turn increments and let the engine idle for 10 seconds or so after each adjustment to stabilize.

If the idle mixture screw never got a rich stumble, then either something is plugged up or the slow jet is WAY too small. Since you think you have a 45 slow, then I would say the later isn't the case, but could be wrong. A 45 should be pretty close for your setup, at most a 48.

I'd go out and get it up to full temp...ride the bike for about 20 hard miles. Then turn the idle mixture screw in until it stumbles. Then shut the engine off and carefully count the turns in until you get a gentle seat. Then turn it back out to that point again plus 1/2 turn. Then let the bike idle and turn it out in 1/4 turn increments (10 sec idling between) until it stumble or the idle slows slightly. Then set it half way between the lean (in) stumble and the out stumble. Try that. If you are more than 3 1/2 turns out, might try a 48 slow.

Since it sounds like you have the stock slide, slide spring, needle, etc, I would shim the needle .030" with some small washer to richen up the midrange. While you have the float bowl off, check to see what main jet it has in it. The main jet and slow jet will have a number stamped on them. With your set up, I would start with a 45 slwo jet, needle shimmed .030" and a 190 main. And then fine tune from there.

Shu
14th May 2006, 03:44
Here is a graph that shows what parts of the carb do what.

http://xlforum.net/photopost/data/500/CV_Carb_Dynamics2.JPG

Shimming the needle richens the mid range. Increasing the slow jet richens from idle to off idle (plus adds a little bit of fuel throughout the entire rpm range, but it is negligable).

Read this thread as well. http://xlforum.net/vbportal/forums/showthread.php?t=4465

ted
14th May 2006, 03:51
Go one size up on the slow jet first, then adjust idle. Needle does not affect idle. You might want to look into the 1988 needle. There are a few threads explaining it. But then again, after getting the slow jet right you might decide the needle you have is just fine. One carb circuit at a time is a good thought. I haven't heard anything suggesting needing a needle on your bike yet. It is always idle first then work up from there.
Ted

Gone
14th May 2006, 17:29
Shu,
I had gone to that website before but only did a "find" for what I was looking for. :doh The graph that depicts the component effect vs throttle position is a great troubleshooting tool.

Thanks for adding that to the post!

nemo
14th May 2006, 20:06
are you sure it's the carb?

ksoggs
15th May 2006, 18:57
are you sure it's the carb?

No, i am not sure its the carb, back in the begining of the thread we went thru a number of alternate solutions, and this was thought to be the best route to try.

Honestly, i would rather try and replace a $10 jet and fail, and then move on to more serious issues, then i would be to pul the engine and inspect valves or what ever else, only to find it could have been solved by a jet.

But i would be happy to entertain any other solutions, especially if they can be tested or confirmed without major engine work.

What do you think might be the problem apart from carb issues?

Gone
16th May 2006, 00:23
Out of curiosity, what was the last thing you did before you noticed the idle problem? I have found to retrace my steps helps me solve the problem.

Jets are $2.95 at the local indy. You said as you backed-out the mixture screw things got better to a certain point. I would think the 48 idle jet might make things better if not solve the problem. As Shu's chart shows, pilot jet and mixture screw are in effect at that point. But, I think someone mentioned the carb itself. It might be worth some disassembly to blow things out and make sure the passages are clean.

Did you do a compression test? If it's ignition or fuel, the compression will be the same; valve(s) will show lower compression in the rear cylinder (it's the rear, right?) May be worth a fresh set of plugs, although you said they had been in for only 1-week. But, you may consider switching front/rear plugs to see if the problem moves.

About the playing card; when you adjusted the mixture screw, did the one car NOT get sucked into the exhaust as much? When adjusting the mixture, you are adjusting the upper and lower explosive levels; if there's not enough fuel (and resultant gas expansion), there's less exhaust pressure or, as I see it, more evident valve overlap.

Yeah, I know: some of this sounds like BS. I'm not a BSer; just have difficulty explaining stuff.

Please keep us updated!

hoosier xlc
16th May 2006, 01:02
I might be way off base with this one, but did you check the gap on your plugs before installing them? I for one have not had any luck with champion spark plugs and I know that is exactly what HD plugs are. I have had better luck with NGK, and Autolite plugs. As I said in the PM I sent you if you are running the sparplug/headbolt covers, make sure they are seated properly, and the rubber doesn't have a tear or something in them, this will cause a spark arc to jump, and may cause a miss. You might trying turning the lights out in the garage with the bike running, and see if you have a spark arcing someplace. Just a thought, prolly not the correct though, but a thought anyways!

Scott

sfxtech
16th May 2006, 01:11
No, i am not sure its the carb, back in the begining of the thread we went thru a number of alternate solutions, and this was thought to be the best route to try.

Honestly, i would rather try and replace a $10 jet and fail, and then move on to more serious issues, then i would be to pul the engine and inspect valves or what ever else, only to find it could have been solved by a jet.

But i would be happy to entertain any other solutions, especially if they can be tested or confirmed without major engine work.

What do you think might be the problem apart from carb issues?
This maybe way out there, but my bike was showing symptoms like this as well. The front cylinder was very strong, and the back... well....not so. It turned out to be the vacuum line on the petcock. The diaphragm was leaking, and fuel was getting sucked directly into my intake. Sometimes it would run better than others, but it was never quite right. I didn't think it would affect just 1 cylinder like that, but it did. Over time as the diaphragm got worse both cylinders got really bad. I took it to the stealer at least 6 times for it.... then By the time I found the problem and took it in, the plugs were not only BLACK but soaked in gas.

ksoggs
16th May 2006, 03:52
When adjusting the mixture, you are adjusting the upper and lower explosive levels; if there's not enough fuel (and resultant gas expansion), there's less exhaust pressure or, as I see it, more evident valve overlap.

um.. no... i just turn the idle screw... how do i adjust upper and lower explosive levels??

Gone
16th May 2006, 11:03
Sorry, my attempt at explaining the theory of fuel mixture affecting the idle.

How are things going with the idle situation? Any better?

ksoggs
16th May 2006, 12:43
ok i got the 48 jet and installed it and got the bike back together at like 9pm last night... too late to be starting my bike up in this neighborhood.
I got the jet in, bought new wires (accel 8.8mm), and a set of bosch platinum +4 plugs (i am going to do the tuning with my champions or autolites or whatever i have in there now, as i dont want to foul out a set of $8 plugs)

I set my mixture screw back to the 2.5 turns to start on this new jet.. so as soon as i can fire it up without the old folks calling the cops, i will let you know how it goes.

I few other little details that i noticed, that may or may not have any effect on anything.... i got the bike with chrome spark plug covers, not the combined bolt and plug covers, but just the plug covers. I understand they dont effect performance. but the rear cylinder had a rubber groumet that kept the cover from touching anything, and the fronts goumet was missing. I took them both off for the moment. as the new wires i got have super long plug boots, and they dont fit with the covers. Also, for the first time ever i pulled the plugs and both of them look to be in pretty good shape, no more black soot. but now the plugs are almost a yellow dry look. (i am almost certain the soot was from over choking, and now that i dont use choke, it is just entirely too lean. and maybe this new plug coloration is due to the lean-ness.) we will soon find out. I may grab a compression tester on the way home too, just to cover all the bases.

tim4hire
16th May 2006, 19:13
The spark plug covers are usualy the culprit in these circumstances.My experince went like this I got a set of the finned covers grommetts were on my wires were new put them on looked great try to start and no sparky took them off and wulla! Starts up no problems.Went and talked to my indy parts dealer whose employees there are bike builders and they said much to the shops chagrin ( at least they let them be honest) that theyve watched people come in buy a set put them on the bike right outside and wham!the bikes got problems they come back inside buy new wires,coils,plugs,and what not still got problems.They take the covers off geuss what no more problems!Now I asked and they said that yea some bikes are fine with them but they can't figure out why some are more tempermental about those things than others?

ksoggs
16th May 2006, 20:05
ok fired it up with the new jet and no more shiney covers... no noticable difference... seems to run rough no matter what. een with screw in all the way it seems rough, but then again there is hardly any change as i back it out... doesnt really "stumble" even backed way out on the 48. one cyl still runs strnger than the other... I am going to grab a compression tester and go from there.

sfxtech
16th May 2006, 20:23
ok fired it up with the new jet and no more shiney covers... no noticable difference... seems to run rough no matter what. een with screw in all the way it seems rough, but then again there is hardly any change as i back it out... doesnt really "stumble" even backed way out on the 48. one cyl still runs strnger than the other... I am going to grab a compression tester and go from there.
do yourself a favor and check the vacuum port on the petcock. I fought this for a long time, mine did the same thing, I think I may have worn out the adjustment screw from messing with it so much. All the way in, 1/2 turn out, 2 turns out, trips to the stealer... you get the idea.

Just my 2 cents

chrishajer
16th May 2006, 21:14
My $.02: It is very difficult to diagnose something like this over the 'net (not that we all haven't tried.) I just went back and reread the whole thread (twice) looking for something. The problem (for me) with diagnosing something like this without the bike in front of me is that there may be something completely obvious to me, that I would never think to have you check, because it's so basic in my procedure that it's just second nature. So, we lead you down a path, and you come back with your observations, and you have your own ideas about what might be wrong, and we go down that path, and so on.

I checked your profile, and you're in Ohio. I don't know of any shops near you I'd recommend (not that I don't trust the ones who are there, but I just don't know any of them) but my advice would be to find a mechanic you trust to just listen to your bike. To me, your audio and video appear normal, especially for those short pipes. I was looking at a stock TC88/EFI today with SE slip on mufflers, and there's a lot of humidity in the air here, so you can see the exhaust pulses in the pipes, and it looked just like yours to me.

If you're coming to Chicago sometime soon (just take I-80 West 350 miles), I'd be glad to lend an ear, but if not, find someone local you trust. Buy him a beer or a six and go from there.

p.s. I'm an IT guy too, so if you'd like to PM me, we can take it offline.

ksoggs
16th May 2006, 21:26
do yourself a favor and check the vacuum port on the petcock. I fought this for a long time, mine did the same thing, I think I may have worn out the adjustment screw from messing with it so much. All the way in, 1/2 turn out, 2 turns out, trips to the stealer... you get the idea.

Just my 2 cents


h yeah i forgot... i checked that too. i dont know exactly what i am checking for... but there was no gas in the line, no gas came out, the hose seemed in decent shape...
am i supposed to do anything special?
i did this all with engine off... i figured removing that with engine on would cause a major vaccuum leak, as well as cut off fuel supply.
so what else do i look for? what are the symptoms and tests for this petcock vacuum problem? mine seems normal to me, but i dont know if i am just not looking for the right things.


oh and i do have a local guy that is a good friends of my dads... he is an indy wrench and does great work.. but he isnt cheap and usually has about a 1 week waiting list to get the bike to him. so i am just trying to do as much as i can myself. (apart from the fact i like this stuff, and want to learn how to do it all, and you cant learn to walk when your mommy always carrys you)

chrishajer
16th May 2006, 21:31
If the indy does great work, then I would say you should try and learn from him (it would be worth it to see how he solves the problem if there is one.) A week wait is not too long, but I think I would just ride over there and see if he would listen to your bike. It might be something simple, might be nothing at all, but shouldn't cost anything just for a listen.

sfxtech
16th May 2006, 22:09
h yeah i forgot... i checked that too. i dont know exactly what i am checking for... but there was no gas in the line, no gas came out, the hose seemed in decent shape...
am i supposed to do anything special?
i did this all with engine off... i figured removing that with engine on would cause a major vaccuum leak, as well as cut off fuel supply.
so what else do i look for? what are the symptoms and tests for this petcock vacuum problem? mine seems normal to me, but i dont know if i am just not looking for the right things.


oh and i do have a local guy that is a good friends of my dads... he is an indy wrench and does great work.. but he isnt cheap and usually has about a 1 week waiting list to get the bike to him. so i am just trying to do as much as i can myself. (apart from the fact i like this stuff, and want to learn how to do it all, and you cant learn to walk when your mommy always carrys you)
looking at the petcock you will see a square bit behind it. On the bottom of that square bit is a small diameter hose with a 90 degree elbow in it, the hose is much smaller than the fuel supply line, it goes from there directly into your intake manifold. It was easier for me to remove my horn/horn cover, it gives you much better access to get to the hose. Remove that hose (It just pulls off from the bottom) and attach a clear hose of approximately the same diameter (about the size of aquarium air line), apply suction to the clear hose, either with a vacuum pump, or sucking on it. If you see fuel in the clear line, then you have a leak. If it is leaking, that means when the bike is running and the itake is sucking on that line, it is sucking fuel right along with it, causing a STUPID rich situation.
hope this helps, it sure solved all my problems....:tour

Shu
16th May 2006, 22:46
If you are adjusting the mixture screw and not getting any measurable results, then either the engine is not fully warmed up, the enrichener is sticking on a little bit, or you have dirty in one of the passages in the carb.

Oh and I run the spark plug covers (see my picture in my sig). I took the rubber gromet out, pushed my wire ends through it (so that the boot is what touches the chrome cover) and then snap them onto the plugs.

a45junkie
16th May 2006, 23:17
ok if it doesnt die when you put the screw all the way in, your idle speed must be really high.
put the screw in and slow down the idle till it dies
then turn it out a couple turns and adjust from there

chrishajer
16th May 2006, 23:22
One thing I haven't seen mentioned yet: if you turn the fuel mixture screw out more than 3-1/2 turns or so, you run the risk of the screw vibrating out, since it's held in by spring tension and a tiny little o-ring. If the mixture screw falls out, you might as well go buy a HSR42.

Also, turning the screw out more than 3-1/2 turns or more is no different than turning it out 3 turns. More than 3 turns out and you need a larger pilot jet.

ksoggs
17th May 2006, 00:09
my bike idles right around 1k always has.

i did a compression test and both cyl. register identicle

i swapped spark plugs and positions on the coil, (thinking maybe one half of the coil was shot)

nothing changes.

have not yet tested sucking on the vacuum to the petcock... going to try that now.

ksoggs
17th May 2006, 00:34
ok, i tired the vacuum suck test. got some clear line, and poped it on the petcock and sucked till i passed out and not a drop of gasoline.
I started the bike with the vacuum line off covered by my finger... and it was sucking strong... if i let go or even let it a little air in it got real crappy or nearly died.

So i am going to rule out the following

vacuum leaks
petcocks
Compression leaks
Valves
coil/plugs/wires


so i am open to other suggestions....

I am going to tool around for a little bit and try to warm it up, see if i have any better luck adjusting it then.

cuz adjusting this new jet hardly does anything. screw all the way in, and it runs ok... screw 1 turn out to 100 turns runs all the same, a little rougher than all the way in, but never coughs or studders.

Shu
17th May 2006, 04:50
If you can turn the idle mixture screw all the way in and it does not die, then again I suggest removing the carb, disassembling and cleaning all passages and checking everything.

However, since you say it sounds like it is dropping the cylinder every other revolution, then to me that sounds like ignition.

tim4hire
17th May 2006, 09:48
Ksoggs just tryin to help here maybe the guys could use some more info did you buy the bike used and what upgrades were already done?What upgrades have you had done?Do you Know if you have an ingition type that can have the "Map" downloaded to?Also when did you notice this?After you had any work done to it?

Gone
17th May 2006, 11:55
Rechecked the Clymers; normal idle is 950 - 1050 rpm.

ksoggs
17th May 2006, 16:09
Ksoggs just tryin to help here maybe the guys could use some more info did you buy the bike used and what upgrades were already done?What upgrades have you had done?Do you Know if you have an ingition type that can have the "Map" downloaded to?Also when did you notice this?After you had any work done to it?


Yes, sorry i thought i had mentioned this earlier....

i bought the bike just a few months ago... i got it as it sits now... the only things i have done to it are change the oil, put in new plugs, wires, and a turn signal bulb.

oh, and now the jet, and the carb tuning attepts...


i know nothing about the ignition or the MAP..... from what i can tell based on paper trails and looks... the ignition is fully stock.

the bike has run really rough since day one... at first i just thought it was the way sportsters were supposed to be... (this was the first sporty i have ever dealt with) but later i learned that it was overly lumpy, and something just wasnt right.

I am contemplating upgrading the ignition as that is the only major engine component that hasnt been upgraded.... I have a post in the ignition forum asking for suggestions on a good ignition, but after a few days i have no responces yet.

once i am going the bike runs real good, but you can still feel that back cylinder missing. I am sure it would run even better if both cyl were running well. Again, i am not a seasoned sporty rider... this thing seems crazy powerful and fast as it is now... but i am told based on all my bike has on it, that it should be soil-yourself fast.

so i mean if it never ran any better than it does right now i guess i wouldnt mind too much... but i cant imagine having a gimpy cylinder is good for the longevity of the engine. and if i got the performance, i wouldnt mind being able to use it.

I put a mech. stethoscope to both heads to listen for any funny noises, but both heads are the same, i tested compression on each, and both seem the same, I checked for intake leaks, both seem sealed up tight.

I am running out of options....

I have a friends whose dad has been a harley man for YEARS... i am going to let him take a look as soon as it stops raining (been raining a week straight here)
see if he finds anything i havent yet. but he is used to the older bikes, and i dont know how much help he will be on these newer ones.

oh also... while running at idle.... if i pull the back plug boot... it keeps chuging along, more lumpy, but a steady rhytmic bump bump bump bump

if i put the boot back on, it goes back to the bump bump bump bump bump bump bump bump bump bump bump...

if i pull the front plug it just dies almost instantly.

chrishajer
17th May 2006, 16:26
oh also... while running at idle.... if i pull the back plug boot... it keeps chuging along, more lumpy, but a steady rhytmic bump bump bump bump

if i put the boot back on, it goes back to the bump bump bump bump bump bump bump bump bump bump bump...

if i pull the front plug it just dies almost instantly.
I think you're on to something there! If you pull the rear plug wire, the bike still runs, because the front is the only cylinder doing meaningful work. If you pull the front plug wire, it dies, because the rear is doing no work. So, the problem is with the rear cylinder.

Now we're getting somewhere.

I know you said you checked for an intake leak (I think you did anyway.) But maybe there is a rear cylinder intake leak around the manifold. how did you check, or can you check again?

If you swap the front plug to the rear cylinder (plugs, not wires) and repeat the test with pulling the wires, does it still die when you pull the front cylinder wire? (that would show that it's not the plugs that are the problem.)

Head gasket leak on the rear cylinder (you would typically hear that.)

Pushrod or valve problems in the rear cylinder? Did you do compression and leakdown tests already?

Is the problem any different when the bike is hot vs. cold?

ALSO, going along the lines of the intake leak - if it runs crazy strong now, but the idle is bad, due to the rear cylinder, that too points to an intake leak. Intake leaks affect the idle more than when the bike is under power. It can still run strong with an intake leak. Idle will just be crap.

I think you're getting somewhere here.

ksoggs
17th May 2006, 16:57
I think you're on to something there! If you pull the rear plug wire, the bike still runs, because the front is the only cylinder doing meaningful work. If you pull the front plug wire, it dies, because the rear is doing no work. So, the problem is with the rear cylinder.


i have suspected this and been suggesting that for some time, but many people kept telling me "nah it is fuel mix" so i listened... but that path seems to lead me no where


Now we're getting somewhere.

I know you said you checked for an intake leak (I think you did anyway.) But maybe there is a rear cylinder intake leak around the manifold. how did you check, or can you check again?


I ran the bike normally at idle... and then took a can of carb and choke cleaner and hosed down both intake ports at the Y-pipe, figuring if there was a intake leak it would suck some of the carb cleaner into the cylinder and cause it to sputter or choke (if i spritz some carb cleaner in the AC intake while it is running it coughs and nearly stalls and then blows a puff of black smoke) so i figured i would get similar reslts if it sucked it in via an intake to y-pipe leak.

I was just told about the propane test.. i will try that tonight... (turning on but not lighting a porpane torch and pointing it at the y-pipe seals to see if the idle INCREASES)


If you swap the front plug to the rear cylinder (plugs, not wires) and repeat the test with pulling the wires, does it still die when you pull the front cylinder wire? (that would show that it's not the plugs that are the problem.)


I have swapped the plugs back and forth to assure it wasnt the problem... and even put new plugs in, plugs have no effect at all. I did not try the wire pulling test AND changing plugs, just cuz i assume the plugs are both fine. the wires on it now are both BRAND NEW and made no difference, so i am also assuming it isnt the wires.

I guess it could be something with the length of wire... maybe the coil isnt sparking enuf to send a good spark down the wire to the back cyl... i could put the old back (long) wire on the front and keep the new back (long) wire on the back... that way we can rule out wire length as a variable.

i am really stretching here..


Head gasket leak on the rear cylinder (you would typically hear that.)

Pushrod or valve problems in the rear cylinder? Did you do compression and leakdown tests already?


i did buy a compression tester, and both cylinders read the same...

first time i ever did this... so to make sure i did it right....

I pulled both plugs
put the tester on one cyl
cranked it over
each crank bumped the needle up a jump untill the needle reached and stuck at like 120 (psi??) i think that was the reading...

then moved to next cyl... did same... registered the same...

i did not see any way to do a leakdown as the tester i have just has a valve that hold the needle at highest pressure reading... and then a button to relese the pressure


Is the problem any different when the bike is hot vs. cold?


well it runs better warm, as anything would... but no there is no night and day difference... when it is cold it just acts cold...


ALSO, going along the lines of the intake leak - if it runs crazy strong now, but the idle is bad, due to the rear cylinder, that too points to an intake leak. Intake leaks affect the idle more than when the bike is under power. It can still run strong with an intake leak. Idle will just be crap.

I think you're getting somewhere here.

I agree with that as well... but you can still feel a miss even under acceleration and cruising speed. it is less appearant, but still there.

I also felt the exhaust under throttle... locked the throttle at a lil over 2k and felt the exhaust...

same thing...

front.. P P P P P P P P P P P P P P P P P P (strong and steady)
back.. p p...p.....p p...p.....p p...p (weak and pulsating)

chrishajer
17th May 2006, 17:20
i have suspected this and been suggesting that for some time, but many people kept telling me "nah it is fuel mix" so i listened... but that path seems to lead me no where

Kind of why I mentioned "going down one path" - but we have to start somewhere.



I ran the bike normally at idle... and then took a can of carb and choke cleaner and hosed down both intake ports at the Y-pipe, figuring if there was a intake leak it would suck some of the carb cleaner into the cylinder and cause it to sputter or choke (if i spritz some carb cleaner in the AC intake while it is running it coughs and nearly stalls and then blows a puff of black smoke) so i figured i would get similar reslts if it sucked it in via an intake to y-pipe leak.

Yes, that's how you do the test. The idle might go up (if the spray is flammable) or down (if it's not) but based on spraying some into the air cleaner (which is what I do too to see if it's going to go up or down) yours should go down, but it did not. Weird.

The other thing that can happen is the sprayed fluid seals the (minor) leak, and the bike runs better, but doesn't get sucked into the engine enough to cause it to die.

My money is still on intake leak (without seeing the bike of course.)

I was just told about the propane test.. i will try that tonight... (turning on but not lighting a porpane torch and pointing it at the y-pipe seals to see if the idle INCREASES)

That's a good test too.


I have swapped the plugs back and forth to assure it wasnt the problem... and even put new plugs in, plugs have no effect at all. I did not try the wire pulling test AND changing plugs, just cuz i assume the plugs are both fine. the wires on it now are both BRAND NEW and made no difference, so i am also assuming it isnt the wires.

It's not the plugs then.


I guess it could be something with the length of wire... maybe the coil isnt sparking enuf to send a good spark down the wire to the back cyl... i could put the old back (long) wire on the front and keep the new back (long) wire on the back... that way we can rule out wire length as a variable.

You could do that. For your bike, the length of the wire doesn't matter much. There are specs for the resistance based on the length but the coil does not care how long the wire is.


i am really stretching here..

Yep :p



i did buy a compression tester, and both cylinders read the same...

first time i ever did this... so to make sure i did it right....

I pulled both plugs
put the tester on one cyl
cranked it over
each crank bumped the needle up a jump untill the needle reached and stuck at like 120 (psi??) i think that was the reading...

then moved to next cyl... did same... registered the same...

That's correct-enough. You should have the throttle locked wide open when you do the test. The numbers will be higher and more accurate. But if they're the same, that's good. A Thunderstorm top-end should have more like 160PSI hot, with the throttle open, depending on the cam. But 120, and equal, probably rules out compression as a problem.


i did not see any way to do a leakdown as the tester i have just has a valve that hold the needle at highest pressure reading... and then a button to relese the pressure

It's a different tester. It's more expensive. It would tell you if there were leaking valves or rings. If you don't have it, there's plenty of other stuff to check first.



well it runs better warm, as anything would... but no there is no night and day difference... when it is cold it just acts cold...

OK



I agree with that as well... but you can still feel a miss even under acceleration and cruising speed. it is less appearant, but still there.

I also felt the exhaust under throttle... locked the throttle at a lil over 2k and felt the exhaust...

same thing...

front.. P P P P P P P P P P P P P P P P P P (strong and steady)
back.. p p...p.....p p...p.....p p...p (weak and pulsating)


Hmm, this seems to conflict with your 'soil-yourself fast' comment :) but I understand what you mean.

ksoggs
17th May 2006, 17:40
Hmm, this seems to conflict with your 'soil-yourself fast' comment but I understand what you mean

well see that part almost scares me.. cuz it is FAST now... my car is fast... and this bike as it is now makes my car seem like it is a pinto.

so if it is this fast with a gimpy cylinder, i am almost wondering if i should just leave it as a one cylinder for my own safety.

the previous owner said that he used to enter it in dyno contests and won in his class every time he entered.

chrishajer
17th May 2006, 17:43
Don't leave it broken. Running on one cylinder is not good. Even if it's better when the RPMs are up, it won't fix itself. Any dyno sheets or numbers? Sheets would be better to see the curve. But numbers would be good too.

We can always adjust it so your throttle doesn't open all the way to make it slower for you once it's fixed ;)

OR we can change the gearing to make it slower!

Or ......

ksoggs
17th May 2006, 19:46
i was waiting for you to say

"or we could pull the engine and put it in my bike"

chrishajer
17th May 2006, 20:19
:roflblack

Come on up to Chicago. I could use a 5-speed.

ed_in_az
17th May 2006, 20:26
I finally looked at this thread, read some of the later posts here. I don't have much to add, but I would pull the intake manifold and pipes and look in to see if there is any visible obstruction. Additionally I'm wondering what would the symptoms be if the breather was plugged on the rear head?

Good luck.

chrishajer
17th May 2006, 20:35
I think pulling the manifold is a good idea too, if for no other reason than to check the condition of the seals. You might see something interesting there anyway when you take it apart.

Also. if a breather is plugged, the crankcase gasses will find another way to escape: through the weakest gasket, past the rings and back into the carb or out the exhaust, or normally, just out through the front head breather. It's just not ENOUGH breathing but it will still breathe.

ksoggs
19th May 2006, 03:20
ok after some advice from a harley mech... re-did the compression tests...

one stroke compression is 90psi on both cylinders.

multistroke max pressure is 180psi on both

(the back cylinder actually read slightly higher on both)

the first compression stroke jumped her to 90, then second bumped it to about 140, then third pump hit 180ish.

I dont know what these readings are SUPPOSED to be for a 10:1 engine, but they are nearly identicle, so that makes me think compression and valves are fine

I also found out i have the screamin eagle ignition module for the 883 engine... but it is no longer an 883... the dealership tells me unless it is pinging real bad there is nothing to worry about with the module.

the dealer had no idea what could be wrong, want me to bring it in so they can make money off me...

called my dads indy mech, and he is booked and is supposed to be calling me back...


In the mean time i think i am going to get a new ignition.

what does everyone think of the crane hi-4 fireball?

should i go for single fire or dual fire?

chrishajer
19th May 2006, 05:15
Compression sounds fine and like you did it correctly this time. 180 PSI sounds about fine for 10:1 but it really depends on the cam. 180 PSI is a good running street motor.

The 883 module has more total advance IIRC than the 1200 module. If it's not pinging I think it's OK - I need to check the specs to be sure though.

the dealer had no idea what could be wrong, want me to bring it in so they can make money off me...
MAYBE, it's the type of problem they need to see to have any idea what the heck is going on. Maybe, just maybe?

Why are you getting a new ignition? Why not find and fix the problem first? Change only one thing at a time for best results.

ed_in_az
19th May 2006, 05:46
I'm new to Harleys but not to engines. Cheap plugs will give you cheap results and you won't really get it tuned until you put decent ones in. It'll quite possibly change once you get good plugs and you'll be tuning again.

Hmmmmm. That reminded me of my last Japanese cruiser. It only ran well on Platinum plugs. It ran really really well on them and like crap on regular plugs. It must have had an electrical glitch, but I just used the platinums and all was well.

KC_Sportster
19th May 2006, 05:54
Hmmmmm. That reminded me of my last Japanese cruiser. It only ran well on Platinum plugs. It ran really really well on them and like crap on regular plugs. It must have had an electrical glitch, but I just used the platinums and all was well.

Deleted my original post when i read further that the plugs were changed out on this. I've experienced just what you mention with Japanese bikes. Don't want to get off topic but what brand of plugs do Harleys like best?

ed_in_az
19th May 2006, 06:00
Deleted my original post when i read further that the plugs were changed out on this. I've experienced just what you mention with Japanese bikes. Don't want to get off topic but what brand of plugs do Harleys like best?

So far mines on the stock HDs. I did run champion cheapies on my 1st Sportster and it did fine.

chrishajer
19th May 2006, 06:49
The HD plugs are made by Champion, but that doesn't mean they're identical. Champion is just the OEM. There are specification differences, so there is no exact cross reference from Champion to HD. And who knows, maybe Champion saves all the plugs that pass QA for HD, and packages the rest up for Pep Boys?

ksoggs
19th May 2006, 12:35
MAYBE, it's the type of problem they need to see to have any idea what the heck is going on. Maybe, just maybe?


I am aware of that... I didnt say "i refuse to take it in" or "i wont pay a dime" But if i am going to take it anywhere, and pay anyone i would rather it be my dads indy, he has helped me out sooo much in the past. he is always willing to stop what he is doing and talk me thru things, or give me advice, if anyone is going to get my business it would be this guy. So far he his helped me a ton on the phone, and i have never gotten to the point of paying him to do anything, because he always gives me what i need over the phone and then i just do the work myself.


Why are you getting a new ignition? Why not find and fix the problem first? Change only one thing at a time for best results.

well, mainly because i have not found the problem yet, and sometimes you need to replace things to determine if they were the problem. A number of people have questioned ignition, timing, coil, spark, etc... Well all of the above can be checked and confirmed with an ignition upgrade. Right now as mentioned i have the wrong SE ignition and what seems to be the stock coil.
I want to change the coil to see if it does anything, but i want to get away from dual fire, and i dont have a single fire ignition, so i cant buy a single fire coil, and i would rather not spend the money on a dual fire, just to replace it when i get my single fire ignition
I also dont want to spend a long time tuning it and timing it, and all that just to have to re-do everything again after the new ignition. So i figure i could just buy the whole deal, new single fire coil and single fire adjustable ignition. A few of them i like even have a seperate timing control for the rear cylinder, so thinking that might prove a great diagnostic tool in finding the problem.

I totally understand where you are coming from... and i am trying to NOT do that.. i dont want to cover up the real problem behind some fancy gimmick or be off changing the constants before isolating the variables...

But that 883 SE ignition really bugs me. the way i see it, the only real difference between the 883 and 1200 is compression, displacement, and flow. So i have to imagine if you make two models one for each engine... the 883 is going to be suited for low compression, smaller combustion chambers, and more restricted flow. and the 1200 model designed for the opposite. Well i need that opposite, my bike is better flowing and higher compression than the 1200 even. And since everything else i have tested has passed muster, this "wrong" module is standing out like a sore thumb. The stealership guy told me the same thing when i asked "can i use an 883 SE module on a 1200?" they said "yeah not much difference, shouldnt bother ya" and then i went on to tell him why i was asking, and what i have... and then he changed his tune... "well yeah, with all that stuff, the slight differences between the modules might be amplified and you very well may need a different module i never came across that but i wouldnt rule it out"

That is just how i see it. I know i am not a professional, and you guys have alot more experience in this particular area, but have any of you been in this exact place. I have had a TON of great advice, and learend alot here... but it is sounding to me like i just have some wacky 1-in-10000000 issue that isnt anything you will find in a book.
"and the SE ign module is a great lil upgrade for every need, you can even run the 883 module on the 1200 for a slightly different curve (but if you do so be sure to not run the firestorm heads, buell jugs, bassini exhausts and forcewinder intake combo with the 883 module, as the rear cylinder may not recieve enuf spark for full combustion)" I doubt you will find that published anywhere... and it is doubtfull anyone on this board even has the ability to test that... so i gotta go out on a few limbs....

When you are fully stock, troubleshooting is alot easier... the further custom you go the more custom and personalized your problems and solutions tend to become. (i have a jeep that has about 30k in modifications and upgrades on it... needless to say the chrysler dealer is no longer much use to me.)

chrishajer
19th May 2006, 16:08
I am aware of that... I didnt say "i refuse to take it in" or "i wont pay a dime"
I never said you did and didn't mean to imply that. I was specifically addressing your comment:

the dealer had no idea what could be wrong, want me to bring it in so they can make money off me...
My only point, and I'll repeat it again, is that maybe they want you to bring it in because that's the best way for them to fix it. Maybe they, like me, just want to help you fix it without hours and hours of discussion. Might be quicker in person.


But if i am going to take it anywhere, and pay anyone i would rather it be my dads indy, he has helped me out sooo much in the past. he is always willing to stop what he is doing and talk me thru things, or give me advice, if anyone is going to get my business it would be this guy. So far he his helped me a ton on the phone, and i have never gotten to the point of paying him to do anything, because he always gives me what i need over the phone and then i just do the work myself.
Sounds like you have a good relationship with him, and the reason a lot of shops are so booked is that they are good and have a backlog of work. I would certainly stick with him.


well, mainly because i have not found the problem yet, and sometimes you need to replace things to determine if they were the problem. A number of people have questioned ignition, timing, coil, spark, etc... Well all of the above can be checked and confirmed with an ignition upgrade.
There's a serious flaw in that logic, and a lot of people make the same mistake. They think they've 'replaced everything in the ignition system' when they do the coil, module, plugs, and wires, because people tend to focus on components. There's a lot more that has to happen for the ignition to happen. There's the ignition switch, the run/stop switch, battery, circuit breakers, cam, and most importantly for me, the WIRING. Unless you've replaced all of that (and there's no reason to) you haven't replaced the ignition system. It can lead to a false sense of security: "Well, I've replaced the ignition system, so it can't be that" and you move on to something else, when it can still be ignition related.

Ignition system upgrades are just that: upgrades. They are not for fixing problems like this, IMHO.


Right now as mentioned i have the wrong SE ignition and what seems to be the stock coil. I want to change the coil to see if it does anything, but i want to get away from dual fire, and i dont have a single fire ignition, so i cant buy a single fire coil, and i would rather not spend the money on a dual fire, just to replace it when i get my single fire ignition
I also dont want to spend a long time tuning it and timing it, and all that just to have to re-do everything again after the new ignition. So i figure i could just buy the whole deal, new single fire coil and single fire adjustable ignition. A few of them i like even have a seperate timing control for the rear cylinder, so thinking that might prove a great diagnostic tool in finding the problem.

Those are all good reasons for installing the new ignition system. However, installing it to try and fix your unbalanced cylinder problem is a bad idea. i wouldn't suggest buying any component until it is determined definitively that the component is bad.


I totally understand where you are coming from... and i am trying to NOT do that.. i dont want to cover up the real problem behind some fancy gimmick or be off changing the constants before isolating the variables...

We're on the same page there, then. :)


But that 883 SE ignition really bugs me. the way i see it, the only real difference between the 883 and 1200 is compression, displacement, and flow. So i have to imagine if you make two models one for each engine... the 883 is going to be suited for low compression, smaller combustion chambers, and more restricted flow. and the 1200 model designed for the opposite. Well i need that opposite, my bike is better flowing and higher compression than the 1200 even. And since everything else i have tested has passed muster, this "wrong" module is standing out like a sore thumb. The stealership guy told me the same thing when i asked "can i use an 883 SE module on a 1200?" they said "yeah not much difference, shouldnt bother ya" and then i went on to tell him why i was asking, and what i have... and then he changed his tune... "well yeah, with all that stuff, the slight differences between the modules might be amplified and you very well may need a different module i never came across that but i wouldnt rule it out"

I will find the curves for both so we can stop guessing. I can't remember for sure what the difference is on your bike between 1200 and 883.


That is just how i see it. I know i am not a professional, and you guys have alot more experience in this particular area, but have any of you been in this exact place. I have had a TON of great advice, and learned alot here... but it is sounding to me like i just have some wacky 1-in-10000000 issue that isnt anything you will find in a book.
I doubt that it's a 1 in 10 million problem. But you're right, it's not going to be in the troubleshooting section of the manual. It is going to take more than that.

And, yeah, I haven't been in that EXACT place: I doubt anyone has. But I did have a similar problem. (mine was a bent pushrod, but from your description, I wouldn't even suggest that's your problem.) You need a mechanic to listen to it, and give you some ideas. Indy you trust is a great start.


"and the SE ign module is a great lil upgrade for every need, you can even run the 883 module on the 1200 for a slightly different curve (but if you do so be sure to not run the firestorm heads, buell jugs, bassini exhausts and forcewinder intake combo with the 883 module, as the rear cylinder may not recieve enuf spark for full combustion)" I doubt you will find that published anywhere... and it is doubtfull anyone on this board even has the ability to test that... so i gotta go out on a few limbs....

You won't, but seeing enough problems, you start to see patterns develop and it becomes part of your troubleshooting technique. That's why you want the guy with 30 years experience helping you, not the n00b out of MMI in his first year.


When you are fully stock, troubleshooting is alot easier... the further custom you go the more custom and personalized your problems and solutions tend to become. (i have a jeep that has about 30k in modifications and upgrades on it... needless to say the chrysler dealer is no longer much use to me.)
Agree 100% - BUT we're here to help you by sharing personal experience and by offering (hopefully) helpful advice. I am confident we'll find the problem, even if I'm wrong on my diagnoses along the way. It's all part of the process.

-- Chris :banana (my daughter just wanted to see the dancing banana :) )

ksoggs
19th May 2006, 19:15
I agree with everything, and i greatly appreciate your help and the help everyone has offered me so far.
I feel aweful that we are on page 8 and counting. That is alot of help.

I want to get it to my indy... already tried my friend-mechanic... but as i stated he wasnt much help, as he is all about the old bikes and these new ones are hebrew to him.

when i explained my problem to my dads indy, he immediately sprang back with a few questions, how many miles, have you done this, did you notice that? etc.. which made me feel good, it wasnt the... "hmmm well... maybe..." that i get alot of places... he said it sounded like a burnt valve... but i assume that would be indicated by poor compression in the one cylinder. which i dont have. he told me to run a one stroke compression test on both cylinders and call him back with results... when i called he was gone... so im waiting to hear back and see what his answer was...



so i anxiously await his next diagnosis.

chrishajer
20th May 2006, 00:01
Sounds like you're getting somewhere with the indy. That's good. Can't wait to hear what the next thing is.

I just started another thread re: troubleshooting. I will post the URL here in a minute.

--Chris

ksoggs
20th May 2006, 00:18
ok just got off the phone with the Indy, he says with compresson readings like mine it is most likely ignition related. plugs, wires, module, coil, something like that...

so i told him all the numerous tests i did with ignition... and he agreed everything sounds good, the only thing left is module, which is the only thing i cant test. he told me i will have to bring the bike to him next week to have it checked out.

chrishajer
20th May 2006, 00:24
I just posted some thoughts on the subject of troubleshooting in general:
http://xlforum.net/vbportal/forums/showthread.php?p=377356#post377356

--Chris

chrishajer
20th May 2006, 00:32
ok just got off the phone with the Indy, he says with compresson readings like mine it is most likely ignition related. plugs, wires, module, coil, something like that...
Agreed - the compression doesn't lead me to believe there's anything there. It would be nice to have a leakdown test to verify absolutely that there is no engine damage, but it's not likely anyway, so you can try other things.


so i told him all the numerous tests i did with ignition... and he agreed everything sounds good, the only thing left is module, which is the only thing i cant test. he told me i will have to bring the bike to him next week to have it checked out.
I wish you luck. The nice thing about going to a shop sometimes is that they have access to spare modules, so they can change a component without you having to buy it, to verify their diagnosis.

--Chris

ksoggs
20th May 2006, 23:29
ok more updates...
Took it to the dealer this morning, as i mentioned earlier, they told me they would need to see it in person and to bring it up on saturday. So i did... they were swamped, but they sent a tech out to the parking lot with me and he gave a listen, and i went over all the painful details with him.

He basically said there is no good way to test a module, short of yanking it out and plugging it into a diagnostic computer ($$$). He said the best test is to hop on the bike and ride for 30 miles or more on a hot day. he said most modules with problems will overheat and kill the ignition till they cool down. so he said take a nice long drive on a hot day and see if the module keeps up, if it cuts out, and wont fire back up till it cools down, then you may have a bad module.

(on that note, there have been a few times where i have started my bike, walked away, got distracted and when i walked back out the bike was shut off and there was this ticking noise. like just a single TICK every 15 seconds or so till i turned the ignition off... i wonder if this is simialr to what he is talking about... a bike sitting at idle with no air to cool it could have the same effect as a long ride on a hot day.. so i am not ruling out module YET.)

but the thing he said to test before anything else.... timing. He said it is possible for the timing to be so far off that the one cylinder hardly fires.
he said to time it the best i can and then see hoe it is.

did just that, came home and found the timing was WAY off.. ya know the grooves in the plate that holds the module, and rotates to adjust the timing.... well it WAS all the way cranked counter clockwise... and the mark was no where in sight. after almost a 1/4 to a 1/3 of the slot travel, i found the mark... lined it up, locked things down... and i noticed the idle had sped up by a few hundred rpm... so i took it back down to the factory 1050 my manual suggested... it sounded ALOT smoother, idled alot better, and wasnt nearly as ready to stall on me when i let off the clutch.

Felt the pipes hoping to feel equal pressure, but to my dismay, the rear cylinder was still less than half the pressure put out by the front. the front now has TONS of exhaust pressure... the back still has almost none.

So i still havent fixed THE problem... but along the way i keep improving things and making the bike in general alot better.

Oh after all this i went back to the mixture screw... it was a little more responsive now... you could feel AN effect... but still no "rich stumble" or "lean stumble" so i still could have the mixture way off. the 48 jet helped alot, but i may still be a jet off... i have no idea... wednesday i go to my indy, i have faith in him.

chrishajer
21st May 2006, 01:46
Sounds like you're on the right track. Looking forward to Wednesday.

--Chris

Shu
21st May 2006, 04:29
The 883 ignition curve doesn't ahve any more total advance thqan the 1200 (if my memory is correct), but has a steep advance slope curve. It advances quicker and totals earlier. I have an 833/1200 conversion with 10:1 compression and SE cams. And I run the stock 883 ignition. The curve is fine. Even though I still think your problem is ignition related since you decribe it as "dropping the cylinder every other revolution". But I do not think it is the curve of the module that is causing you problems. The timing needs to be backed off. Set it about 17 degrees at 1000 rpm idle (fully warmed up). The stock setting is 20 degrees by the way. Then pull the carb apart and CLEAN it because regardless of why the rear cylinder is dropping, the mixture screw still should be working properly. USe some carb cleaner (spray can with straw) and blow through all the passages after you have complete diassembled the carb. Then put it all back together, check the float level, check the diaphram for the slide, etc. While you have it off I would go ahead and replace the intake manifold gaskets, they are cheap and wasy to do. then put it all back together and dial in the idle mixture.

Ignitions typically either work or don't. The will begin to fail when hot at first and eventually just burn up. Coils act much the same way. Check your coil wire inputs, pull them off, clean up the terminals and maek sure the wire ends tha plug on to it are cleaned up on the inside.

When you were int he ignition, did you see any corrosion on the ignition pick up? Might want to just pull the ignition and clean the brass cup real good.

ksoggs
26th May 2006, 17:46
For all you following along and helping me out so far... I made a new post detailing my trip to the Indy.
My dad loves this guy and thinks he is the best things since sliced bread, but i have my doubts. Please read up and tell me what you think.

http://xlforum.net/vbportal/forums/showthread.php?t=29202

mikeymike
21st September 2006, 04:28
yeah mine does the same thing...but still runs great

mikes71sporty
21st September 2006, 21:33
Are you sure both cylinders are fireing? My bike was running on the front cylinder only for a couple of days....I posted an earlier thread on it... Good luck