Likely cause of idle loss when stopping hard after a high speed run?

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I think that what was written in #25 is a clue.
When you brake hard, equivalent to going steep downhill, fuel goes to the front of the tank.
Learned that on my 16H going downhill, though on that machine hard braking is impossible.
 
I believe I found a smoking gun, (but there might be more)

I had a ignition wire that was close to the rotor on my ignition, it was close enough to wear a very small hole in the insulation, When stopping once in a while it would touch the rotor and cause a ignition ground out and die or backfire.
Likely cause of idle loss when stopping hard after a high speed run?
 
That's a nice find, but how does it affect comming to a stop? Wouldn't the misfire be constant?
 
maylar said:
That's a nice find, but how does it affect comming to a stop? Wouldn't the misfire be constant?
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not if the wire was moving enough while stopping to short out but away from the rotor otherwise, The photo shows the wire not in the original as found position but pulled out, it was underneath the rotor , real close.
 
jimbo said:
not if the wire was moving enough while stopping to short out but away from the rotor otherwise, The photo shows the wire not in the original as found position but pulled out, it was underneath the rotor , real close.
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While maybe true in your case, id expect it to be a very rare cause in other bikes.
 
Jumbo .... If you still working on this issue , I just read that out of whack carb balance can cause your symptoms at least it does with a pair of Bing carbs ...
 
MexicoMike said:
Because it is a known carburetor thing - it's why dashpots were installed on car engines back in the day, to slowly return the throttle the last few hundred RPM to idle, regardless how quickly you let off the pedal. The other option was to set a higher idle speed which also solves the problem but the dashpot eliminated the issue AND allowed the lower idle speed.

Obviously, some carbs/engine setups are more sensitive than others.
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This is what my mechanic told me. I had the same issue. Bike started and idle fine. First 5-10 minutes stop and go no problem. Take it out for an extended run at speed (55-70) over the same course and would idle out (just die at the intersection).

Took a video and share with my mechanic. He recommended adjust the idle after reaching operating temp. This fixed my problem with my Amal carbs. He said there is no vacuum adjustment on these carbs, so you must be at operating temp before setting the idle speed.
 
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