i gotta 97/98 kx80. i took parts off eachother to make one bike. its gettin fuel,compression,and spark but still wont turn over. about every four or five kicks itll let out a loud puff of air out the exhaust. any ideas on whats wrong?

 

Is the timing off? you can pull the 3 timing covers.. there is one big one on the side of the head, and one small and even smaller one on the side of the crank case.. the two smaller ones should come out with a flat screwdriver.. make sure there is minimal slack in the timing chain. and that both timing marks line up correctly. Once you have the timing covers off, pull the plug and you can turn the motor over easy with a socket and ratchet..

 

And if you find anything like that on your KX 80, run far away from it because it has morphed into something else.

I would throw some new reeds in and a fresh plug, then see what happens.

 

Did not realize that it was a 2-stroke bike.. All the small bikes we have.. are all 4 stroke..

 

Yeah, I kinda figured you were thinking of a klx, though I don't know if they make that in an 80.