engine uncotrolled reving.

[maximus1029]

My sons Apex has not been ridden in 6 months. I started it up last week and it started fine. I put it up on the lift, just to get the engine some running time. After about 10 minutes the engine started to race up and the overflow bottle blew up. The kill switch didn't work, and when I was getting ready to pull some wires off of the CDI it finally died. I am not looking for a new bottle before I start it again and try to figure out what is going on.

If anyone has a suggestion as to why it raced up it would be greatly appreciated.

[Doug10]

Sounds like it was loaded up on fuel to the point where it went hog wild.

[o4twinpeaks]

To me sounds like it went lean or out of fuel.

[FISH ON!]

Sounds like a fuel prob for sure. If it has been sitting for 6 months with fuel in the carb then first thing to do is a thorough carb cleaning and some fresh fuel. The bottle blowing is likely due to the tiny vent hole on the cap being plugged or closed up....doesn't take much. Completely disassemble the carb and clean it real good then put some fresh gas in it and let her rip. Be carefull not to mess the float setting when pullong the bowl off. Good Luck.

[mmsoup]

could be a couple of things

By the way, do you still have compression? You sure it didn't burn up?

We had two incidents over time with the throttle cable being stretched too tight which led to wide open throttle and it wasn't immediately apparent what had caused it. In both cases we had put Powermad Mud Covers on the bark busters a bit too tight and they had pinched the throttle cable.

Or, like Todd said it may have leaned out. Lean motors develop unstable idle and can have trouble idling down after they have been throttled up

The bottle blew cause things got too hot (Kinda makes you think lean again) And trust me, Todd can corroborate that my kids have had their share of trouble with overheating.

I second the check on the carb and if you know how, take a look for air leaks as well, around the base gasket, intake gasket, case halves and carb boot. We leak test ours frequently (Cause Dad has had to rebuild them more than he wants to take responsibility for lol)

Good luck

[redonkulousruntsracing]

crank seals could have dried out and retracted causing the air leak, something else to check