kfx 80 will not run need help

[mtmike]

i got a 2006 kfx80 that is hard starting, i cleaned the carb 3 times checked the manifold o- rings, and reed valve.i shot gas into the carb ,it somtimes acts like it is firing, but will not start, I burned the exhaust pipe to make sure it is free flowing, it seems to have good spark,,,,,went out to try to start it, well it fired up and i keep it running for about 5 min, turned it off,let it cool off a little bit, tried to restart it , and its back to the no start problem,,, i could really use some help with this problem,,,,,,,

[mtmike]

still haveing problems starting, after turning over the motor with it making nois like its fireing, the thing finnaly started, pushed it out of the garage, and would you believe, the dame thing will only go in resverse,, no forward,, i dont see any way to shift it into drive,,,i am not seeing the picture, i thought this model only went forward,,,,,HELP-HELP

[mtmike]

still cant get kfx 80 running wont tart cleaned carb a couple times, checked the reed valve, gets spark , put a on,off pitcock on,still didnt work ,its electric start, i turn it over for quit some time it might pop ,or fire, but this takes way to long,,, need help

[GeneralV]

If you know its not the carb, the next most common thing to fix on these is changing the piston rings or ring, depending if ot has a stock piston or not. I have 7 of them in our collection. Take the head off and cylinder and see if it is a 1 or 2 ring piston. Stock has 2, a lot of aftermarket only has 1. It will start with a burned up piston but you cant hardly make any power unless you choke it. They are easy to change and you can get a set of rings on egay for cheeeeep. $20 or so.

[mtmike]

it seams to have compression, when it starts it runs good, but when i stop it and try to restart it it will not start , i put a compression tester on it and it jumped up to 100 lbs, i also did a leak down test and blew the plug off the exhaust,i pluged the exhaust with a hose clamp and a plug that slid over the tail pipe.

[BertaRobinz]

I have had a bad experience even with the new kfx80. The exhaust also doesn't seem to work quiet well. Damn, I need an alternative to it. cheap trucks for sale

[NovaKaw650]

Quote: Originally Posted by mtmike

it seams to have compression, when it starts it runs good, but when i stop it and try to restart it it will not start , i put a compression tester on it and it jumped up to 100 lbs, i also did a leak down test and blew the plug off the exhaust,i pluged the exhaust with a hose clamp and a plug that slid over the tail pipe.

Why would you plug the exhaust??
If you have fuel and (good) spark, it's likely that the compression is too low.

[mtmike]

when you do a leak down test you plug intake,and plug the exhaust, to see what the leak down is past the rings.piston must be at tDc, compression stroke

[NovaKaw650]

2 stroke engine.
The piston is at TDC, so it's above the ports. You don't plug anything. In fact, if you could completely plug the exhaust and intake, you would blow the crank seals out.

[mtmike]

sounds good ial try it again