2 strokes

[alanTDM]

Anybody on here know the ins and outs of 2stroke engines?
Just rebuilt and got bike started 2nd kick but cuts out after a few mins after revs increase Starts again ok but then still cuts out.

[Mark_Able]

Any noises when it cuts out? Could be being starved of 2 stroke oil? :

[jimmer]

Starved off petrol the revs will rise when it trys to get fuel could be blocked fuel pipe breather in tank.

[jj]

check for air leaks on inlet rubbers or exhaust

[finbar]

Yes...lots! [smiley=thumbsup.gif]

[crewy]

Could be the main jet blocked with a bit of crap, the air adjuster screw on the carb might need some tweaking, has it got a rave valve? they get a bit seized up and dont open. What engine is it on?

[Scotty]

Start with the basics, next time it cuts out, turn the fuel off immediately and crack the drain screw on the float bowl to see if there's any fuel in the carb - could be blocked fuel tap or filter, maybe the needle valve needs checking. Check for air leaks, reed valves sticking or broken.. you say just rebuilt - did that include crank seals? :-?

[Bennett]

Mine raises, however, it doesn't die again, but only sometimes.
Something to do with the carb? Check it.
BTW, I am no expert, I've been riding since last October.

[alanTDM]

This is a Kawasaki KMX200
The engine was stripped,new crankseals new piston and rings,all gaskets are new ,power valves are spot less carb was stripped and cleaned ,new air jet cause old one was to big ,float height is now with in tolerance 21mm-23mm.Reeds and block ok cant see any sign of cracks on the inlet rubbers and air cleaner is new.
checked the petrol in the bowl all ok and from what i can tell choke is working ok aswell.
sometimes does not always slow down from 3k rpm quick either when you shut the throttle off and when it does hit idle it cuts out.Air jet screw is set at 1/1/2 turns out tried it in various positions.
the way it cuts out would seem to be electrical rather than a fuel prob checked kill switch aswell thats ok and side stand switch in fact anything i an think of.

[Jon_W]

Sounds like the carbs are gummed.... The only electrical thing that would even come close to these symptoms is a cdi sensor fault...

I had this with the Honda when I last started it after a lay up. Just kept running it till the carbs cleared.

Are you getting big clouds of black smoke? Sounds like carburation...