[Toehead]

Hey guys! I've been diagnosing a mid-throttle stumble for a while now. I thought it was the carb sync. Yesterday, it became much worse and the bike would barely run. At this point, it was clearly an internal carb problem, even though they were supposedly just serviced. Took them apart, and there was a nice coating of rust and white goo over everything! In addition, one of the carbs had the idle and main jets switched.........



Cleaned everything out nicely (ground the mixture tabs while I was in there) and it is a whole new machine.





Never trust that something has been done correctly until you do it yourself!

 

[LRCXed]

Never trust that something has been done correctly until you do it yourself!



Very well put toehead. Good to see another one lives and breaths fire again. Good job!

 

[Toehead]

Never trust that something has been done correctly until you do it yourself!



Very well put toehead. Good to see another one lives and breaths fire again. Good job!

False alarm

The stumble came back today after a nice long drive. It is a breakup (seems lean) between the main jet and the idle jet. Full throttle works well. It only rears its ugly head when you are cruising.. Suggestionsas to the circuit involved?



-Brendan

 

[Toehead]

False alarm

The stumble came back today after a nice long drive. It is a breakup (seems lean) between the main jet and the idle jet. Full throttle works well. It only rears its ugly head when you are cruising.. Suggestionsas to the circuit involved?



-Brendan

Took the carbs apart again. I was trying to avoid taking the idle jet out with an easy out, but that's my task tomorrow. The stumble must be found!



Larry, thanks again for all the informative posts and pictures explaining the various circuits in the carb.

 

[Toehead]

Figure i'll pose a question while I am here....





I have a pair of carbs from '79 with no accelerator pump and a pair of carbs off my '80 with the pump. Both are in similar condition.





Which would be the best style to rebuild?

 

[Blue Fox]

If everything else is equal, I would re-build the 80's with the accelerator pump. That added shot of fuel just seems to help out.

 

[Toehead]

All better!



Ultrasonic cleaning and a complete strip down fixed all my problems.

A list of problems I found on the carb:



Top seals in backwards

Jets switched on one carb

Perforated ACV on the left

ACV frozen on the right

Calcium deposits throughout