hesitation under full throttle

jay760

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Question for the carb specialists,
When under full throttle I have a slight hesitation when changing gear, the bike is running slightly rich, would the hesitation be caused by too much fuel until the engine catches up or too little? whilst I realize I need a smaller main jet, I'm not sure which way to go with the needle,
Using 36mm slide carbs not original cv
 
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Are you blipping the throttle during shifts, or hard-banging it?

If you drop the throttle enough between shifts, the pilot circuit wakes up and starts delivering fuel simultaneous with the needle jet, and can create momentary overrich.

Just a thought, how to rejet is dependent on your bike...
 
I have Mk 11 Amals 300 main jet will have to look at the rest, have the needle at its weakest setting, but wouldn't have thought this would make much difference as it's on full throttle, 1''3/4 exhaust with reverse cone megas.
Normally run dellortos and have never experienced this with them as they pump fuel in to compensate for it.
 
Oh, man, it's been 40 years since I fooled with Amals. If they're old, could check the slide fits. Also, see if they have shallow cutaways. Could reduce pilot circuit a little, and lower the floats a little. These are just some things to try, but the best is zonal plug chops, especially on those main jets...
 
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