running like crap! pls help

[southslide]

hey fellas,
about 12months ago i got a 140 (not sure of motor brand) and the guy had put an inner rotor kit on, a massive mikuni carb and a huge exhaust on it. when i first got the bike it ran awsome and allways did, till.. i burnt out the inner rotor kit.. my bike sat there for about 6months doin nothing untill the other day i pulled a magneto outof another bike of mine and put it in the 140 so i could ride it, when i got the bike started it wouldnt idle, will not rev for crap like im struggling to get the revs up, its backfiring like crazy and running VERY VERY hot, and it has became an absolute PIG to start it =/

ant help would be great thanks.

 

[MiniFighter]

Did you check your valve clearences?

New fuel or still old?

Check plug?

 

[sean01]

as above plus clean the carb out and drain the old fuel out..

 

[Cactus Jack]

Another possibility (as indicated by these words "when i got the bike started it wouldnt idle, will not rev for crap like im struggling to get the revs up, its backfiring like crazy and running VERY VERY hot, and it has became an absolute PIG to start it ) ...... could be .... due to the engine sitting unrun for a long time , the valve guides could have dried out and one or both valves have gone down , stayed down , kissed the piston ... and got bendeded ...

You should ALWAYS remove the spark plug and valve adjustment covers to watch the rockers and valves plus feel for any tight spots while you gently turn the engine over by hand after it has been sitting for an extended period of time ... You should also change the oil and tip the bike over on both sides before even thinking of starting it too ...

Another good tip would be to oil the cam , rockers and valve stems with an oiling can before even attempting to turn the engine over by hand ...

Water in the float bowl can also cause similar running symptoms ...