Bike has no top end

[2StrokeCruiser]

Hi all, just got my 250 smoker top end rebuilt and the jetting kinda dialed in, its ruining a 165 main and a 45 pilot, running 40:1, the float adjusted and the needle in 3rd position.  It was runs great for about 15 minutes then it loses power like nobody's business. The powervalves open fine, but like i said, its bogging down 5th gear full throttle, and it just doesn't have that hard hitting power down low. It's also impossible to kickstart if its hot. I have to either bump start it or wait a half hour or so to kick it over. Any ideas. 

Before i forget, reeds are fine too. 

 

[Turboloader]

Hi all, just got my 250 smoker top end rebuilt and the jetting kinda dialed in, its ruining a 165 main and a 45 pilot, running 40:1, the float adjusted and the needle in 3rd position.  It was runs great for about 15 minutes then it loses power like nobody's business. The powervalves open fine, but like i said, its bogging down 5th gear full throttle, and it just doesn't have that hard hitting power down low. It's also impossible to kickstart if its hot. I have to either bump start it or wait a half hour or so to kick it over. Any ideas. 

Before i forget, reeds are fine too. 

 

Bro, the best "guess" would be to check your ignition system, start with the kill switch, then go to the coil, and usually the cdi is ok its solid state, check all wiring connections for corrosion, clean and snug em' up, then the big booger, the generator, you will need a puller for the flywheel/rotor. the stator rotor combo may be on its last leg. Its a hit and miss scenario.  Usually if you have good compression, good fuel air mixture, good fuel, the last culprit can logically be your ignition system, good luck, the dude!

[Still Bill]

Clogged fuel filter.

[redbikejohn]

Fuel tank breather blocked?

Might be stator coil. If it's a ktm (you don't say) it's a weak point but on the plus side you don't need to pull the rota stc say typed above.

Plug cap ?

Float level all OK?

[Kawi4life]

Piston and rings time?

[orangyktmthing]

Ignition coil or stator?

[2StrokeCruiser]

Piston and rings time?

a few hours 

[2StrokeCruiser]

I pulled the head off, one of the 0 rings was unseated so i put it back in and checked my pistion while i was in there, all good with it. Put bike back together, and it fired first kick. Rode it around a bit and shut off and started back up a few times. It had all of it's top end back. Now it is bogging down again and wont start...

[2StrokeCruiser]

Any idea why this is?

[2StrokeCruiser]

Even though this thread died, i figured it out. Base gasket was cut, local shop had a new one it fires right up now. Time to sell this sucker