high rev

hello :) after repairing some stuff on my bike and when i went to try, it started but like it was full throttle. it did a little wheelie and the chain snapped out. i barely touched the throttle when starting it, just that tiny stroke to get the engine running. i changed the intake manifold and...

I have a 2-stroke china kit and originally I was able to hit the clutch while holding down the throttle and i could let go and it would rev down quickly and idle, but recently even if im not putting any gas on while moving and hit the clutch it revs super high and loud, and i can make it idle...

got a brand new 2 stroke gas bicycle kit when i ride at a high rpm and pu the clutch in the rpms dont come down but if i engage the clutch a tiny bit it will bring it back down to normal idle speed and it idles just fine whats wrong someone help please

This has recently happened to my '82 Hobbit were it will only idle with the choke on, and then quickly high rev and die with the choke off unless your giving it a bunch of gas. Is there a fix? I've taken it into a shop cleaned the carb twice, just put in a new crank so I highly doubt there is a...

when i get into higher speeds on my 80cc beach cruiser, I hear a fast knocking sound and would like to know if I should be worried about that? or what is causing it?