RPMs'racing during shifting or throttle release. RESOLVED

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Ok here’s one. The bike rides fine but when releasing the throttle to shift, the RPM’s do not reduce for a few moments. I have check to see if the throttle slides was sticking due to air flow, as I have heard , but this is not the case. Here are some details
Pason ignition set a 30 btdc at around 4 g's.
Mikuni TM 34 mm flatslide
This is what has changed. I added a MKiii timing cover. I switched the white/black and the Yellow/black at the terminals of the Pason trigger as instructed. The instruction said that it would be severely retarded the other way so I wanted to make it proper. I had it running well before with the wires swapped but maybe that was a matter or rotor position.

Anyway I do not know if this is an ignition curve issue or a carb issue due to the switch in wb and yb wires, or something else all together.
 
Re: RPMs'racing during shifting or throttle release.

Doesn't an air leak cause the same symptom
 
Re: RPMs'racing during shifting or throttle release.

Too rich a mix will speed up on backing off WOT. Check all that implies.
Might try switching the triggers leads back, just in case and not for sure.
Of Course physically sticking slide/cable type symptoms you already aware.
Make sure kill switch is good functioning, not to fix problem just kill it before it grows.
 
Re: RPMs'racing during shifting or throttle release.

pvisseriii said:
This is what has changed. I added a MKiii timing cover. I switched the white/black and the Yellow/black at the terminals of the Pason trigger as instructed. The instruction said that it would be severely retarded the other way so I wanted to make it proper. I had it running well before with the wires swapped but maybe that was a matter or rotor position.
I must be missing something. Did you have to reverse the wires at the trigger because you swtiched over to a MkIII timing cover? WTF? Here's the instructions for the Sure-Fire. I must have missed it.
http://www.britcycle.com/Manuals/337PA2inst.pdf
 
Re: RPMs'racing during shifting or throttle release.

Well it has been at least 3 week and I have figured it out. The needle was not true. the flat slide would function perfectly but a slight bow in the needle would keep it from coming to idle just long enough to scew up shufting. Pulled the needle and could not visually see the bow. Rolled it on a flat surface and sure enough. Trued it up and functionality returned.

It is easy to see how this could happen with that nasty spring and the little green retainer you have to put in place. Just the price you have to pay for the pureness of the flat side carb.

This could easily happen with any needle on any carb. Check your needles. If them duel setups aren't syncing up and you have scratched your head after resleeving, it just might be a bow in the needle.
 
Re: RPMs'racing during shifting or throttle release.

pvisseriii, thanx for dropping the other shoe. I learned something = to keep in mind bent needles and symptoms, which I'd not thought possible w/o on purpose stomping.
 
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