Engine shutting off after revving out.

#1
So recently i i staled a performance kit on my preadator 212 swapped mini bike. Bike ran great except i would feel it kind of top over up top and break up at higher rpm (that could just be me reaching the limit, may need bigger valve springs) but anyways, today while i was riding, the bike shut off. Full of gas, fuel open, etc. It seemed ok so i started it up and it happened again. Now it is happening every time i ride it, spark plug looks okay so i don’t think it’s that, carb is brand new and haven’t had problems with it between the 4 days of me ripping on this thing. I am unsure of the problem.
 

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#4
It could be that, however i had no problems with it until yesterday, and i rose it just as normal the other 3 days prior.
Well you’ll have to start checking stuff to figure out the problem, gotta figure out if it’s a fuel problem, spark problem etc.
Could you have sheared a flywheel key?
Just throwing common stuff out there
 
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#5
What carb, spark plug, main jet, etube, etc are you running? Elevation? Do you have a tach? If so what rpm is this happening at? If you dont have one pick one up on amazon for <$15.

My guess is you may be running rich up in the rpm range if you swapped jets or significantly above sea level.
 
#6
So recently i i staled a performance kit on my preadator 212 swapped mini bike. Bike ran great except i would feel it kind of top over up top and break up at higher rpm (that could just be me reaching the limit, may need bigger valve springs) but anyways, today while i was riding, the bike shut off. Full of gas, fuel open, etc. It seemed ok so i started it up and it happened again. Now it is happening every time i ride it, spark plug looks okay so i don’t think it’s that, carb is brand new and haven’t had problems with it between the 4 days of me ripping on this thing. I am unsure of the problem.
Run it with the spark tester on it. When it quits look for the light. It’s quick and easy elimination.
 
#8
Sounds like a sliver of fuel hose caught above the needle seat or maybe caught in the main jet. It made its way to a small hole that it won't fit through so now it's restricting fuel flow during full throttle operation.
 
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