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thessler
31st March 2011, 22:45
Hi
I think I have a problem, not sure. I followed the video in the stickys and mine will not line up the same. According to my interpretation of the video, with the front cylinder TDC you move the point plate untill the points just open at 40 deg. while manually holding the advance mechanism advanced.

On mine the plate is all the way over to the left as far as it can go and as soon as you touch the advance the points are open. If I move the plate to the right the points open and stay open. wheras in the video there is some movement of the cam lobe before the points open.

I just assembled the motor and have tripple checked all the timing marks before I put the cover on. Something in my gut says it's off but I can't see how.
This is a 1983 motor, used to have electronic ignition and has been changed over to points. I don't know if that matters or not.

Please give any thoughts. Thanks, Tom

draimondi
31st March 2011, 22:49
I don't know if i'm interpreting this correctly but sounds like you just need to adjust your points gap?

thessler
31st March 2011, 22:56
I'm probrably not explaining it right. The points are adjusted properly first. I'm good with that, but the point plate doesn't seem to want to rotate far enough to the left to get propper static timing. It is not hung up or anything it just seems the cam lobe is to far advanced to begin with.

draimondi
31st March 2011, 23:00
basically what you're looking for is when the points are on either the large or small lobe you have a point gap of .018 when on the lobe. when you're off the lobe the points should be closed. If they aren't closed then when you're off the lobes then you just adjust the points there is a screw there that you loosen and adjust the position.

when you put the engine at TDC then you should be just before the lobe and when you advance the cam it should open the points.

The video says and shows this much better than I can describe but i'm not sure of what exactly your issue is here. To me sounds like the points are always open?

draimondi
31st March 2011, 23:05
ok so that makes a bit more sense. So when the engine is at TDC you're already on the lobe rather than being just before it?

Sounds like you need to adjust the advance cam. I believe there is a bolt at the very end you can loosen and adjust that advance cam..... please research first and maybe someone else here can give you some advice on this before you do this. I have never done this and don't want to steer you in the wrong direction.

My guess is that the advance cam needs to be adjusted though and i'd do a bit of research on that.

Hope this helps.

72 Ironhead XLH
1st April 2011, 01:16
you dont static time at TDC, you use the vert line in the window ,thats the advance mark. Adjust the points first,Lock your weights in full advance, put a piece of cig paper between the points, rotate plate untill paper slips out. This should time you at 40 deg. advanced. unlock the weights and the timing retards for starting.

thessler
1st April 2011, 01:29
Yes I am using the vertical line in the window. My problem is if I lock my weights at full advance the points are open, in fact they are open way before full advance.
as soon as I move the weights at all the points open, there is no room to back off by rotating the plate. It's rotated all the way over counter clockwise . If I move it clockwise at all the points will be ontop of the lobe and wide open.
It may work but it sure doesn't feel right or look right.
Thanks, Tom

Doc o
1st April 2011, 01:54
If I'm reading this right it sounds like what I just ran into on my bike.
I checked out the advance weights and they where shot.
I replace them with a set of accel, problem went away.
Not saying this is your problem but you might check your advance unit.

draimondi
1st April 2011, 02:11
you dont static time at TDC, you use the vert line in the window ,thats the advance mark. Adjust the points first,Lock your weights in full advance, put a piece of cig paper between the points, rotate plate untill paper slips out. This should time you at 40 deg. advanced. unlock the weights and the timing retards for starting.

I knew I'd be wrong!! Haha I did mean using the vertical line not TDC as I stated. I knew what I was thinking... Hope you get the issue fixed.

Shadowdog500
1st April 2011, 10:22
You time the bike using the 40 Before TDC mark for the front cylinder not TDC.

Your marks on your flywheel are probably different than mine. For some reason HD changed the flywheel marks around for different years. in addition aftermarket flywheels use different marks as well. To find the 40 Before TDC mark for the front cylinder on your bike simply put the rear cylinder on TDC and look for the 40 Before TDC timing mark for the front cylinder nearest the hole. Use that mark to time your bike as I do in the video and you should be fine.

Chris

Hopper
1st April 2011, 11:20
Hi

This is a 1983 motor, used to have electronic ignition and has been changed over to points. I don't know if that matters or not.

Please give any thoughts. Thanks, Tom


If all else fails to reveal the problem, suspect your aftermarket advance unit/points cam.

If you use the search box at the bottom of this forum page (not the useless one at the top), you will find others on here have had similar problems. It turned out to be the Taiwan Trash auto advance unit and/or points cam were made wrong, wrong angles, wrong location etc.
Some were 180 degrees out and the owner had to take the points backing plate out and put it back in "upside down" to get the right cam lobe operating the points for the front cylinder.

I forget now which cam lobe is the correct one for timing the front cylinder, the thick one or the thin one, but it is possibly in the manual, or you can find it in a search on this site. Others here who have done the job more recently may be able to tell you.

Seems like the Vulcan auto advance unit with the roller bearing pivots has provided better quality for some on here than the cheaper units.

Obviously, if you had the engine running before the rebuild with this ignition setup, it must have been ok then so should be ok now. But still worth checking you have the right cam lobe operating points for front cylinder.

thessler
1st April 2011, 15:05
Got it
Shadowdog hit the nail on the head. If I bring the rear cylinder TDC. A new mark a single dot appears in the window, i'm guessing this is it because now the plate is in the middle and there is room for adjustment.
Would anyone know why there is a line on the flywheel just like the video ? it seems to be lined up with the front TDC.
Anyhow there is less stress on me today I was sure I lined up the cam and pinion marks up.
Thanks for all the help ,Tom

draimondi
1st April 2011, 15:23
Great to hear! Thats the other thing that i failed to mention.... and its hard to see if you're turning the rear wheel and not looking into the window.

There is more than one mark and its not always the same throughout the different years.

Glad you got everything worked out!!!

Stick_Man
1st April 2011, 22:08
Got it
Shadowdog hit the nail on the head. If I bring the rear cylinder TDC. A new mark a single dot appears in the window, i'm guessing this is it because now the plate is in the middle and there is room for adjustment.
Would anyone know why there is a line on the flywheel just like the video ? it seems to be lined up with the front TDC.
Anyhow there is less stress on me today I was sure I lined up the cam and pinion marks up.
Thanks for all the help ,Tom


I know this shit all too well :p

The cycle in the video is a 70's something MC; the line is the advance mark for those years but is TDC for 80's IHs.

You want advance mark for 80's IHs; (check your manual). Otherwise you know how to get tdc, just go backwards from there to the first mark you see (on the front cyl)

Also: are you sure you have rear tdc? I know on front tdc you can not move the cam; I could only do it on front advance mark. The single dot is front advance on the '81....

Stick_Man
3rd April 2011, 16:14
Just curious -- on the 80's IH's where exactly is the front advanced mark -- the single dot -- supposed to be? Near the bottom right or smack inthe middle of the window like pictured in the manual?

On my cycle however, an '81, it looks like the dot from earlier years...i.e. it shows up down near the bottom of the window. But it's advance for mine NOT tdc like it's supposed to be for those years.

I guess it's an earlier crank, but how are the marks -- front tdc and advance -- switched????

Boy aren't old cycles fun? :D

Shadowdog500
3rd April 2011, 18:26
There is a photo that shows flywheels with all of the marks by year somewhere in the stickies. I'm surfing on my phone right now so I am not going to be able to find them for you.

Never assume that your flywheel has the proper marks for your year. Go through the procedure I gave to locate the mark on your flywheel.

Chris

IronMick
3rd April 2011, 19:20
With the engine not running i have always seen the mark pretty well in the center of the timing hole. With the engine running and using a timing light it seems to vary a bit but i can usually get it pretty close.

thessler
4th April 2011, 14:44
stick man
yes it turned out the front timing mark is one dot.
I saw the video and found the same line in the video and went with it. My mistake, in the video he metions your marks may be different but once I saw the same line I just got tunnel vision and thought this was it and I messed something up.

Stick_Man
4th April 2011, 15:46
With the engine not running i have always seen the mark pretty well in the center of the timing hole. With the engine running and using a timing light it seems to vary a bit but i can usually get it pretty close.

just to clear, the dots are supposedly different for pre '80 and post '80.

According to the book, pre '80 has a dot that shos in the lower part of the window. post '80 upper part of the window.

What I mean is that is appears I have a '79 dot; it shows low in the window; on an '81 cycle. But mine is front advance and not tdc like a '79.

jonnybravo
4th April 2011, 16:06
here's one to look out for, my 84 has bar = front TDC, next single dot =rear 40 deg advance, then double o's =rear TDC, then another single dot for front 40 degree advance, and yes working on old bikes is fun

IronMick
4th April 2011, 16:18
E80 is not the same as L80. One is the dot the other is the bar.

Never rely on what is in any manual unless you are magic and know with absolute certainty that the flywheels are original. Always look in the timing hole with the piston at TDC.

Roadster Rick
4th April 2011, 16:32
I have an E80 (Feb) and the bar is TDC and one dot (low in the window) is 40 degrees BTDC.....Thanks to Mick's posts I checked piston position to verify marks before setting the timing....Thanks Mick!!

Stick_Man
4th April 2011, 19:10
Yeah i did tdc after giving up trying to figure out the marks from the book. Although I almost broke a pencil in there while doing so.

I was just wondering ...