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smackie
6th October 2007, 03:45
well finally got the dyno run in on my little set up, ther only mods i have mod as far as tuning are the custom map for turbota on the ignition and i put a 170 main jet in there to ensure it was rich for break in.

bike feels like it has a ton of power doing short roll on from 3000 rpm up but at WOT wasnt pulling as hard as i had expected. still feels like a world of improvement over my last set up but the number dont seem that far apart. though i might be running a little lean in parts, but to my surprise.....

anywho, i am going to attempt to tune it myself at least to get the A/F ratio closer to what it should be any tuning tips would be appreciated and with tuning (after seeing the dyno) what can i realistically expect to get from this now?

last set up was SE intake, Cycle shack slip ons and 551 cams

running the SE mikuni 42 which should have (this is mostly conjecture after talking to the boys at the harley joint)

25 slow, 96 needle on middle clip and a 170 main (i put the 170 in). dont know what the mixture screw is set at.

they reccomended a 20 slow, 98 needle on middle clip and a 165. (which i now have with me but not installed)

rfranz1952
6th October 2007, 04:07
Something strikes me as very wrong with that Dyno. The torque and RPM curves should always cross at 5,250 rpm. These don't cross until about 6500. The bottom end looks funky too.

You should get your money refunded or a redo, I think.

smackie
6th October 2007, 04:17
that threw me off...way off at first, but it has two different scales
torque is on the right side adn only goes up to 85 while the HP is on the left and goes up to 105 hp. scales are all dicked up, but if you scale both sides appropraitly it is corect

cjburr
6th October 2007, 04:32
definitely looks rich to me, here's my dyno with the V&H shortshot staggered pipes and the same parts you have.

http://i25.photobucket.com/albums/c97/cjburr/SAVE0009.jpg

You've got the supposed "hottest" 2 into 1 pipe made and according to NRHS's dyno sheets they post you ought to easily be over 100hp and probably 110hp with a great tune on it.

I'm beginning to wonder if a 2 into 1 is worth the money if most of your riding is just every day street riding, it will be interesting if some tuning eliminates some of that massive dip in the torque down low.

Haven't dynoed mine with the Bassani 2 into 1 yet but my heads will be here this week, unfortunately I'm leaving to work on the new Aries 1X rocket for 5 weeks and a week of much needed vacation after that so the dyno will have to wait for me.

I'd definitely get the A/F at around 13 to 1 and see where you are at before you start tweaking the timing and the rest. My TC88 was set at the normal setting for a high compression motor for that dyno and I was blowing oil past my guides due to the bad seals.

Best of luck, I'll be watching with interest, Chris

smackie
6th October 2007, 04:52
thanks CJ,

that is what i was thinking too.

yours is still not together?

XLFREAK
6th October 2007, 04:56
Yes, I agree it is running rich and 13 would be the target number. Definitely use a different dyno machine. Tune the air/fuel mixture so it flat lines at 13. Your power will not only increase it will pull smoothly.

cjburr
6th October 2007, 05:15
thanks CJ,

that is what i was thinking too.

yours is still not together?

soon my friend soon, my new head guy also found me around 15cfm at the low and mid lifts for the .575 cams, so much for the "computer matched CNC porting" at stage3 tailored for my cams and actually got a little more on the high lifts.

I'll put the V&H's back on as the tune is just as it was for that dyno I posted and we'll see if I can break 90hp with my 85hp pipes. Then I'll put on the Bassani 2 into 1 and we'll get a decent comparison between the two pipes.

This may be BS too but the dyno will tell, if it comes across as I don't trust anyone and their claims......it should because I don't.

I hope you reach your goals and that NRHS did their work correctly for you and you don't end up with an oil burner like some of us.

Chris

TnG
6th October 2007, 06:02
Still wondering about rfranz1952 comment, never seen a dyno chart that didn't cross torque and HP @ 5250 RPM. Why does HP not even start until 3000 RPM? If this is just a wide open throttle pull we're not seeing any of the part throttle readings, and therefore can't comment on needle size or settings, the needle will be out of the mainjet, so to bring this chart more inline all I can say is try the next leaner main jet. Keeping in mind it may throw your part throttle setings off. Have you looked at the carb tuning info at the Mikuni site for this carb.? Seems like good info to me.

smackie
6th October 2007, 07:01
TNG.
most dyno charts the hp and torque numbers read even across the board..this one doesnt so it wont cross at 5252.
would be easier to read that way. but still works fo rthat purpose

secondly horse power dont kick in till 3000 grand from what i am assuming is the reversion i see before 3000. HP is below 40 due to that so probably wont read on the chart...this is my assumption at least.

i agree about the carb jetting. just trying to get close...you said you are running a 97 needle right?

rfranz1952
6th October 2007, 07:10
that threw me off...way off at first, but it has two different scales
torque is on the right side adn only goes up to 85 while the HP is on the left and goes up to 105 hp. scales are all dicked up, but if you scale both sides appropraitly it is corect


Yeah, I see that now. Kind of hard to see the right hand scale on the graphic, but it is clearly different. Kind of an unusual (as in not the norm) way to do that.

Gone
6th October 2007, 08:13
If the dyno is telling the whole story, something isn't right........... It really seems to be struggling on the bottom - which might be the pipe/cam combination. But then, it's still soft on top, well below your equipment potential.

CBAS5
6th October 2007, 08:25
Here is what I have to say about it:

AFR too rich
Lines are very jagged: something isn't happy
Power output: should be better for your combination

Overall, the dyno does not look right. Not only do the curves not cross at 5252 rpm, but that's a HUGE dip between 2-3K rpm. That's a drop of 40 there: that is tragic.

Smackie,
Are you able to get the run files from your dyno? Not jpegs, but the actual run files.

smackie
6th October 2007, 17:38
Cbas5,

i am not sure what you mean by files. i am unsure either way but will try and check before i leave again so maybe i can post it if there are individual files of each run.

i am not sure this dyno is right, but my main purpose was to get a base line and the AFR. which i got it seems, just wondering if the choke knob might have been out slightly

where that dip is you dont really feel that unles you are WOT, partial throttle gets through that fine. but WOT it sputters...i wonder if that was it...i am assuming that is that also from reversion.

please explain the jagged line and something not being happy. i am not following and would like some more info on possibilities

lastly wasnt to impressed with the dyno operater, hence why i am going to try at least to tune it myself...not the most confidence in them.

Jimbos883
6th October 2007, 17:58
Smackie all 2 to 1 pipes have reversion down low. Don't believe me just look at other dynos with 2 to 1 pipes it's there. Your dyno is really hard to tell what is going on the because both plots start pretty high in the rpm range nad the values are different. First thing thatIi'd do is find a different dyno shop they don't know what they are doing. A good operator will tell you right off what the problem is by looking at the printout.

I agree fully with CJ and Cbas5 you are very rich, I not all fimilar with the HSR carb for tuning but I hear that they have great info on their website. With all the parts that you have on that bike it should be doing much better, hope you get it sorted out. I don't think you have a big issue with you pipe and cam combo but that's just my opinion. Maybe those RB pipes are another one of those things that don't really perform up to all their hype who really knows. I think you are the first dyno I've seem with that pipe.

NRHS Sales
6th October 2007, 18:47
There are many bad things happening in that dyno. First one is you are obviously way too rich at 12 to 1 afr. You need to be between 13.5-14 to 1 afr for best results. second question is why does it seem your rev limiter is kicking in at 6500 rpms? Was that the dyno operator rolling off the throttle perhaps? Something just is not right at 6500-7000 rpms. See how the air fuel also goes real lean there? thats not a normal thing. That engine can be run at WOT to a full 7,000 with no problem. That alone should give you another 4 hp or so. Get the carb jetted correctly and you should be right around 100 hp.

smackie
7th October 2007, 03:46
he said (dyno operator) that it must have been the rev limiter....rev limiter is set for 7000. he was just letting it off early in my opinion(the "real tuner" said the same thing after looking at it).

to be honest it is not a priority to worry about the 6500-7000 at this point so it didnt mean a whole lot to me.

i installed a 165 main and a 98 needle set on the second from the top (old needle was a 97 second from the top and the main was a 170)

dan
do you think the 165 main and the needle change will get me close or do i need to do more with the main?

obviously i know you arent a internet based walking dyno machine, but i have never tuned one or seen how much of a difference it would make changing stuff

i did take it out for a little cruise today (after the changes) and cant really say i noticed a differance....maybe a little crisper 4000 and up but hard to tell. i tried the roll on and the roll off. kept hitting traffic though. seemed like the motor was still loading up a little during the roll off (rich).

PuddlePirate
8th October 2007, 01:17
I hope you get this stuff figured out, man. I know you've been waiting on this for a while.

CBAS5
9th October 2007, 00:07
i am not sure what you mean by files. i am unsure either way but will try and check before i leave again so maybe i can post it if there are individual files of each run.

The actual run files. You would have to ask the dyno operator. The file that you can read with dynojet's software. That will allow you to plot the lines much better and perhaps gets something that will cross at 5252.

i am not sure this dyno is right, but my main purpose was to get a base line and the AFR. which i got it seems, just wondering if the choke knob might have been out slightly

If you can't trust the numbers, then how can you trust the AFR?

where that dip is you dont really feel that unles you are WOT, partial throttle gets through that fine. but WOT it sputters...i wonder if that was it...i am assuming that is that also from reversion.

That still looks very wrong. Did the engine missfire on you during that point? If so, then did it consistently misfire on all 3 dyno runs?

please explain the jagged line and something not being happy. i am not following and would like some more info on possibilities

It is something that Chris Hajer told me awhile ago. Jagged lines means that something isn't happy. Make it happy and you should make more power. A few possibilities (courtesy of Hajer):

timing
something else in the ignition
something in the chassis
fuel/air mixture
airflow
exhaust


Look at my dyno run:

http://i54.photobucket.com/albums/g115/sgozdzi/Dynos/My%20Dynos/BunnBreather.jpg

Do you see how jagged the lines are? Something there is not happy and I can probably make more power if I can fix it. At the time I was running a custom map. My best guess is that the timing at WOT was off. I will have to retune then put it back on the dyno again.

NRHS Sales
9th October 2007, 00:14
Smackie,
I think you are going in the right direction but Cbass is correct. Jagged lines mean engine is not happy. usually has something to do with igniton.

As far as the jetting. 165 or 162.5 sounds about right. But so many things can influence that, especially your exhaust. i would just be guessing without an air fuel reading.

smackie
10th October 2007, 06:53
Cbas5.
i wasnt able to get the files before i left....I am going to be gone for 3 weeks...well shit would have been nice.

i manually re-scaled it (crunched some numbers) and everything jived so i trust the numbers for the most part. the AFR seems fairly consistant so i dont doubt they are off. partial throttle the thing is a beast but WOT wasnt as impressive. the choke knob was me just pondering possibilities

with the dip i shouldnt say you cant feel it..you can, but isnt that bad unless you are at WOT. i am assuming it is reversion from the pipe, seen other dynos with it running two into one pipes. one person had a thunderheader i beleive and stuck in the anti reversion cones and it was better. to be honest i can deal with the reversion in that spot. dan said with the head set up i would probably have some...so it isnt a big surpirse to me. maybe i will try the lollipop thing again

it does kind of sputter consistantly at that spot when you hit at 2500 rpm.
roll on before that and it just sort of bogs between 2500-2900 hard to describe.

but other then the very basics of what it all means, dont have the experiance to make really edumacated guesses on what to do with a whole lot of confidence.

undestand the jagged line thing now...thanks for the input on everything though

I went with a 165 main and a 98 needle on the second clip (from the top)the old needle was a 97 on the second clip....going back to the 97, after a few rides didnt seem as sharp on the responsive on lower portion of the throttle. might go one more lower on the clip position and take it in again for another dyno. if i am way off just going to have them do it and see what i get.

with the TC88a ingnition aparently they dont have alot of experiance with those, so i think i am going to have to provide the computer and cable if i want them to dick with that.

the more i think about i think rejetting the main and dropping it (needle) a position should get me alot closer, partial throttle (1/2) response was great WOT isnt.

Dan,
one of the guys (the main tuner i guess) said he was pretty familiar with NRHS stuff and they have a 1250 kit for sale in there parts department from yall. they also said that one of there techs worked with/for you guys at some point..i didnt get a name though. will do when i go back. thanks for the input as well. wish i could have gotten up to you guys this summer for a real tune. :(

i will post my next few rounds when i get em down