It's driving me nuts, maybe I can't see the forest cause of the trees😜, but the old quad fired up, carb cleaned multiple times. Shows no signs of vacuum leaks, yet when revved up, it cycles up/ down like you shut the key off& immediately turned it back on. Guess I'll see if the float is jacked up, all I can figure for now

 

Kinda like.....pulsating quickly within 100 RPMs up/down

 

Wow. Float is good, no vacuum leaks, still unsure of pulsating issue...jets are clean, I'm still missing something but what?

 

May try looking in the air snorkel to if critter has built an nest restricting air flow or take airbox lid off to if runs better if does then check the air snorkel for dirtdobber or rats nest

 

Sounds like the rev limiter is coming in. If it comes in at lower revs than it should the CDI may be on its way out. Some bikes also have a lower rev limit when in reverse, can't remember if the 300 has but, if it does, faulty reverse wiring can cause this too.

 

Thanks, intake is all clear as also the exhaust, I was leaning towards limiter but was unsure, thanks for the replies!

 

try new spark plug first before replacing CDI box..

 

Is atv charging good?

 

I'll hookup my multimeter, didn't think about stator output

 

check at batt bout half throttle