Well, just a small amount of dirt getting in there can plug idle passageways and cause the very problem you're having. I had one cylinder start running rough on mine last summer. I pulled the carbs to give them a cleaning and swapped in a spare set. It ran good again with the spares. I cleaned my originals but really didn't find anything that I could see, like large clumps of crap. I put them back on and the bike ran good again. Something like this can happen any time, even like the day after you rebuild or clean the carbs.
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Should the Regulator be too Hot to Touch?
- Thread starter freddy3
- Start date
No, you need to turn it off, adjust gap, then restart and check again. Timing can be adjusted with the motor runing. Just leave the timing plate screws snug, not fully tight, and you can tap the plate one way or the other using a screwdriver and small hammer.
freddy3
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Okay, I think(?) I may've improved things a bit. Here's what I did:
1) I checked the cam adjuster setting, which was perfect (the pin was absolutely flush with the end of the tube). Then, I started the engine and noted that the pin barely moved within the tube (<1mm of travel).
2) I re-measured the point gaps, as per the Service Manual: both still set to .35mm.
3) I re-checked the static timing, as per the Service Manual: same results as before - line on stator is still located to the left of the "F" marks on the stator.
4) I installed a new set of points and gapped them to .35mm.
5) I re-checked the static timing, but the results were the same, so the old points were good.
6) I attached the Dwell meter (set for 8 cylinders) to the right set of points and got the readings in green (though the needle was bouncing around a bit - maybe the width of 1-2 lines on the meter):
7) I reduced the gap on the right set of points (by eye) and retested with the Dwell meter. Still too far over to the right side. So I kept reducing the gap and retesting with the Dwell meter until I got a reading around the 11 mark, which is the red line (n.b. I didn't bother to measure the gap, but to get this reading, I had to adjust the point gap to the point where the contacts were barely separated!).
8) I repeated step 7 on the left set of points, but the best I could get was just shy of the 10 mark (the blue line in the photo above).
9) I attached the inductive timing light and started the engine. With the engine running, instead of the rotor's timing mark being too far to the left of the "F" marks on the stator, it was too far to the right. But I was then able to rotate the points plate to get the firing mark to line up perfectly between the "F" marks on the stator.
After that, I readjusted the idle speed and was able to lower it a bit from its previous ~1500~1600rpm to ~1300rpm (normal is ~1100~1200rpm). It was almost dark and I didn't have my helmet with me, so I was only able to drive it for a few hundred feet around the parking lot, but the idle seemed a bit smoother than it was.
Pardon what may be an obvious question, but it just occurred to me that I only checked the timing with the engine idling. Also, I didn't clamp the advance weights closed as instructed by the Service Manual when checking/setting the point gaps. Do I need to go back and retest @ 2500rpm and/or with the advance weights clamped shut, or is the idle timing sufficient since it was dead-on?
As an aside, I'm amazed at how much of this I've forgotten over the years.
1) I checked the cam adjuster setting, which was perfect (the pin was absolutely flush with the end of the tube). Then, I started the engine and noted that the pin barely moved within the tube (<1mm of travel).
2) I re-measured the point gaps, as per the Service Manual: both still set to .35mm.
3) I re-checked the static timing, as per the Service Manual: same results as before - line on stator is still located to the left of the "F" marks on the stator.
4) I installed a new set of points and gapped them to .35mm.
5) I re-checked the static timing, but the results were the same, so the old points were good.
6) I attached the Dwell meter (set for 8 cylinders) to the right set of points and got the readings in green (though the needle was bouncing around a bit - maybe the width of 1-2 lines on the meter):
7) I reduced the gap on the right set of points (by eye) and retested with the Dwell meter. Still too far over to the right side. So I kept reducing the gap and retesting with the Dwell meter until I got a reading around the 11 mark, which is the red line (n.b. I didn't bother to measure the gap, but to get this reading, I had to adjust the point gap to the point where the contacts were barely separated!).
8) I repeated step 7 on the left set of points, but the best I could get was just shy of the 10 mark (the blue line in the photo above).
9) I attached the inductive timing light and started the engine. With the engine running, instead of the rotor's timing mark being too far to the left of the "F" marks on the stator, it was too far to the right. But I was then able to rotate the points plate to get the firing mark to line up perfectly between the "F" marks on the stator.
After that, I readjusted the idle speed and was able to lower it a bit from its previous ~1500~1600rpm to ~1300rpm (normal is ~1100~1200rpm). It was almost dark and I didn't have my helmet with me, so I was only able to drive it for a few hundred feet around the parking lot, but the idle seemed a bit smoother than it was.
Pardon what may be an obvious question, but it just occurred to me that I only checked the timing with the engine idling. Also, I didn't clamp the advance weights closed as instructed by the Service Manual when checking/setting the point gaps. Do I need to go back and retest @ 2500rpm and/or with the advance weights clamped shut, or is the idle timing sufficient since it was dead-on?
As an aside, I'm amazed at how much of this I've forgotten over the years.
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sgallaty
Antihero
Is your points backing plate bent? or the points plate itself? You should be able to get a decent dwell with the right gap. I'm having a hard time visualizing it right now
also you can test dwell with a conductivity tester. rotate the engine through one full rotation and you can see the degrees through which the points are closed.
also you can test dwell with a conductivity tester. rotate the engine through one full rotation and you can see the degrees through which the points are closed.
freddy3
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Neither plate appears (or has any reason) to be bent and the points are new.
So I gotta figure that either I'm doing something wrong (in setting the gap) or there's something else that's off somewhere...
How do you know when one set of points are at their widest opening?
The Service Manual says to gap the points when they're at their widest opening, but it doesn't say how to tell when that is. So I've been rotating the crankshaft until I reach the "T" mark on the stator (Top Dead Center) and set the right point gap. Then, I rotate the crank one revolution to the "T" mark to set the left point gap. Does that sound right?
So I gotta figure that either I'm doing something wrong (in setting the gap) or there's something else that's off somewhere...
How do you know when one set of points are at their widest opening?
The Service Manual says to gap the points when they're at their widest opening, but it doesn't say how to tell when that is. So I've been rotating the crankshaft until I reach the "T" mark on the stator (Top Dead Center) and set the right point gap. Then, I rotate the crank one revolution to the "T" mark to set the left point gap. Does that sound right?
sgallaty
Antihero
I would just rotate the engine with the plugs out, probably with the rear wheel in 1st on the center until the points opened widest =)
sgallaty
Antihero
check for true in the through-rod, worn/crooked bushings and bearings, and play or wobble at the end of the advance rod shaft, check for centering of the plate....
it sounds like something is offcenter or mislocated.
again though, I'm having a hard time visualizing how you could end up not being able to set the gap right.
Is the rider that lays on the gap cam worn? ... is the gap cam crooked or wobbly? I've seen that -once-....
it sounds like something is offcenter or mislocated.
again though, I'm having a hard time visualizing how you could end up not being able to set the gap right.
Is the rider that lays on the gap cam worn? ... is the gap cam crooked or wobbly? I've seen that -once-....
freddy3
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I agree (that something seems off-center or mislocated), but the advance rod (and advance weight/spring assembly) was recently replaced, so I don't think that's the problem.
What do you mean by gap cam "rider"? Do you mean the felt pads next to the points that actually ride on the cam?
I'm not sure how to check any of the other items you mentioned??
What do you mean by gap cam "rider"? Do you mean the felt pads next to the points that actually ride on the cam?
I'm not sure how to check any of the other items you mentioned??
sgallaty
Antihero
These tolerances are pretty big, I mean you would see it with your eyes that something was wrong if there was an eccentricity big enough to interfere with the points closing.
This is a headscratcher.
yes the felt pads on the cam - just inspect everything and make sure all the bits are attached and in their right places.
This is a headscratcher.
yes the felt pads on the cam - just inspect everything and make sure all the bits are attached and in their right places.
freddy3
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I can't tell you how many times I've been over everything and if something was visually off, I'm pretty sure I'd see it.
Very much a headscratcher.
I have a thought... I can snap some macro photos of the points and advance unit and post them here. Maybe you or someone else can spot the problem.
Very much a headscratcher.
I have a thought... I can snap some macro photos of the points and advance unit and post them here. Maybe you or someone else can spot the problem.
sgallaty
Antihero
Go for it
I want to see the advance plate, and each of the points
I want to see the advance plate, and each of the points
freddy3
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Here you go:
Advance unit (springs, weights, backing plate) replaced late last year
Points replaced last night
How many miles are on the bike and how many on the cam chain? As I said earlier, a stretched out cam chain will cause you to run out of adjustment slot. Mine was right near the end of the adjustment slot. I could still time it correctly but was almost out of slot. After installing a new chain, that put my timing plate right back in the middle of the adjustment slot.
You've managed to get it timed by closing the gaps but you may have closed them too much. I think you can open them back up a bit and still get it timed correctly. Not as big as you had them but not as small as they are now. I would try to get about a .010" gap if possible. Ain't points fun ?
That was something I always wondered about - exactly where to gap the points. They don't give you a specific spot, just where they are open the most. That's hard to judge sometimes. That's what is so nice about the dwell meter, it tells you the gap. Yours may not be giving you the most accurate reading so low on the scale like that. I have a digital one that works quite nicely. It was available from HF at one time.
You've managed to get it timed by closing the gaps but you may have closed them too much. I think you can open them back up a bit and still get it timed correctly. Not as big as you had them but not as small as they are now. I would try to get about a .010" gap if possible. Ain't points fun ?
That was something I always wondered about - exactly where to gap the points. They don't give you a specific spot, just where they are open the most. That's hard to judge sometimes. That's what is so nice about the dwell meter, it tells you the gap. Yours may not be giving you the most accurate reading so low on the scale like that. I have a digital one that works quite nicely. It was available from HF at one time.
freddy3
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Excepting the past 10 or so years, I've been maintaining the bike myself (using the same Service Manual) for the past 36+ years and I've never had so much "fun" with the points (or timing) before. And I'm not sure why that is, but I'm guessing it has to do with my allowing a shop to work on the bike four years ago. Due to a screw-up, they ended up having to replace the OEM regulator, after which all the ignition/charging issues (that instigated this thread) began.
When I initially adjusted the points (to .35mm) and performed the static timing (as per the Service Manual) a couple of days ago, the timing plate was left more or less in its midway position, with reference to the adjustment slot. It's actually still not far off its center position now, after having adjusted the points via the Dwell meter and the timing via the inductive timing light.
If I remember correctly, the bike's got ~47,000 miles and the cam chain's OEM. So I guess it could be stretched. But wouldn't I have found the cam chain tensioner "off" or at least in need of some adjustment if the chain were in need of replacement? Neither was the case when I checked it prior to setting the point gap to .35mm, or, again, yesterday, when I re-did everything with the Dwell meter and timing light.
Of course, I'd need to measure them to be sure, but I'm guessing that the point gaps are probably ~.1mm currently. Are you suggesting that I reduce the gap further to 1/10th of their current opening?
I've actually been wondering whether I should combine the two procedures? That is, re-gap the points to .35mm as I'd done originally (since, other than the slightly rough idle, the bike ran perfectly during the subsequent 3-hour drive) and then see what I get with the timing light (instead of trying to time it statically, with the engine off). Because my gut tells me that my .35mm gapping tool is more accurate than readings I'm getting off a Dwell meter made for an 8-cylinder engine. Does that make sense?
When I initially adjusted the points (to .35mm) and performed the static timing (as per the Service Manual) a couple of days ago, the timing plate was left more or less in its midway position, with reference to the adjustment slot. It's actually still not far off its center position now, after having adjusted the points via the Dwell meter and the timing via the inductive timing light.
If I remember correctly, the bike's got ~47,000 miles and the cam chain's OEM. So I guess it could be stretched. But wouldn't I have found the cam chain tensioner "off" or at least in need of some adjustment if the chain were in need of replacement? Neither was the case when I checked it prior to setting the point gap to .35mm, or, again, yesterday, when I re-did everything with the Dwell meter and timing light.
Of course, I'd need to measure them to be sure, but I'm guessing that the point gaps are probably ~.1mm currently. Are you suggesting that I reduce the gap further to 1/10th of their current opening?
I've actually been wondering whether I should combine the two procedures? That is, re-gap the points to .35mm as I'd done originally (since, other than the slightly rough idle, the bike ran perfectly during the subsequent 3-hour drive) and then see what I get with the timing light (instead of trying to time it statically, with the engine off). Because my gut tells me that my .35mm gapping tool is more accurate than readings I'm getting off a Dwell meter made for an 8-cylinder engine. Does that make sense?
Last edited:
sgallaty
Antihero
I would check that your cam is still properly aligned with your crank. if your static timing puts you off that far, your cams may be out of alignment
