Rebuilt carbs so well the bike won't run off idle.

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Bill Seward

Well-Known Member
Mar 24, 2007
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Holland NY
I tore down the carbs on my '85 a couple weeks ago. New diaphragms / slides, jets, and carb boots. New air cleaner, and spark plugs.
Engine fires up instantly on choke, and will idle OK after it warms up.
Touch the throttle and it dies.
I have the carbs balanced well, and there are no air leaks between the carbs and boots. One thing I did notice was that the slides didn't pulsate when the engine is idling. It doesn't seem that they retract as quickly as I remembered them doing before, either..
Any advice would be GREATLY appreciated.
By the way, this is the first time the carbs have been taken apart, or even removed from the engine.


Well-Known Member
Aug 8, 2008
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Bristol County, Massachusetts
Seems like the new pilot jets are the wrong size.

Note: I have had K&L pilot jets that were labeled same the Mikuni, but they were much, much richer.

A few quick thoughts,
Turn the A/F screws way in and see if there's improvement? Float levels-checked? Make sure the diaphragm needles are correctly installed, the little teet on the plastic bushing has the teet on it, make sure it's in the hole. The needles should have a little wiggle to them. Slides should move as soon as you move the throttle. I think I'd pu;; the plugs and see if there's an overly rich condition too, since they're new.

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