TOPIC:

Finally got my bike running real strong on all four. Put a timing light on it and got it timed out pretty close to perfect.. It backfires a little "pop pop" when I rev it, not alot but some... It ran better than ever but now I have another problem. After running the bike for a good 10-15 minutes pretty hard it wants to die like its completely out of gas. I can pop it in gear and do a rolling start and kind of rev it for awhile to keep moving but it just dies. I've had a similar problem before, and switched out the coils with "new" used ones from a junk yard. I can't think of what else wouldn't work right when it warms up other than the coils, so I'm thinking I need new coils?
Also I (think) I disconnected the pump accelerator circuit by disconnecting the rod from the accelerator pulley to the accelerator pump because I lost the tiny spring that holds the ball and pin in, in the second carb while cleaning it. Could this cause this?
Thanks for the advice,
Ed

Sounds like your gas cap is not venting and causing a vaccuum in the tank. Go for a ride with the cap unlocked and see if it does it again, or if it starts doing it again pull ign key (after 25+ years they all just pull out, don't they?) out and unlock gas cap. Accel pump works only when you twist the throttle and gives a shot of gas till the carbs catch up, is not in operation during cruising speeds.

P.S. I lost one of those "jesus" clips too, only God knows how I found it!!

Post edited by: Bluemeanie, at: 2008/02/09 17:56

Ran it for awhile today with the gas cap off and didn't have the same problem. Do I just need a new gas cap then? Thanks a bunch.
Also: When I try to time it, the book says get cylinders 1 and 4 on the F. It stays steadily at the 1 and 4 mark, and if I try to move it towards the F it putters off and dies pretty quick. Any ideas?
Thanks,
Ed

Also: What are the screws on the outside of the carb that adjust gas mixture? the one on the second carb is stripped out pretty bad, I can't get it to come out so I can replace it. I think I got it in the right amount of turns, could this be affecting it some? How many turns out from a light seat do you usually go?
Thanks,
Ed

Is there a way to move this into carb section...? It probably belongs there . Anyway, played with the bike some more, its not dying while riding anymore, just has a real odd Idle, it'll idle all the way up to 3 RPMs while sitting, just for a few seconds then come down and stay at 1.5 pretty smoothly. Oh, and it lags a bit I think when it revs down.
Example: Coming up on a stop, when I pull the clutch in it'll take a while to get back to idle, like just stay revved and move real slow back to 1 and a half.
Other than that it has the best performance its ever had, those bikes go...
damn.
-Ed

sounds like a vacum leak, check around the carb intake boots,

youtube.com/watch?v=L4taqaZfK9k
Thats the same thing I have going on, except while riding it takes forever for the RPMs to come back down.
Could it be related..? I can't find any vacuum leaks, tried spraying carb cleaner around while running it to listen for a difference..
Ed

Hey! That's my bike.

My trouble was with one coil. When the bike was cold, it would run fine until the bike got up to temperature. Once hot, the coil would not fire until I got the rmps up over 3000rpm. No idle, no fun in traffic. Below is a link to my thread on this.

Link to my problem

Your situation sounds like a vacuum leak to me. I had one of those on the same bike and instead of WD-40 on the carb boots, I used starting fluid. The bike revved up right away. Now, don't go spraying around starting fluid on a hot bike. I was frustrated a the time and didn't care if the bike burned since I had so many problems with it.

After all the fixes, the bike is running great.