My sons Kazuma 50 usually runs great and has had very few problems but now it will not start. He rode it about a week ago and it cut off twice and was very hard to get re-started. We brought it home and now it will not start at all. I have looked at the plug, air filter and carb and can not find any obvious problems. I have pulled the plug and checked for spark and it looked fine. I tried a shot of ether and that did not even help. I pulled the plug and it seems like the compression stroke may be a little weak (doesn't blow my finger off the hole) but the intake stroke pulls hard enough to suck my finger in. It is only about 2 years old and probably only has 50 hours on it so I am hoping it is something simple like a timing adjustment or valve adjustment. Any thought?

Thanks

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Dirt Dobber

I would try adjusting the valves. Someone on here gave me this link,so forgot who, http://www.kaplancomputers.com...als/kmx50_manual2.pdf
I think that this manual is much better than the on that comes with the quads.

do u choke it ??????? and it might be to lean i have had this problem with some of my quads

Also for what its worth check the air vent in the gas cap.Make sure its clear from debri.

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Vbike 250-V4s
Roketa ATV-56A 150cc

after 2 years of riding and 50+ hours you need to check valve clearance. manual says .002 but to be on the safe side and make the valve adjusment last a little longer i'd adjust them to .003-.004, .002 to me just a little to tight.

Thanks for the link, I will give this a try. It looks like adjusting the intake valve will be a little tricky with the steering shaft in the way. Have you done this wothout removing the steering shaft?

Thanks again

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Dirt Dobber

the steering shaft doen't interfer, what i did was to stand the atv up on the back wheels and frame, then is pretty simple to do

I used an old plastic milk crate to set the quad on, I think standing it up would work better. Make sure to double check for oil leaks. I had a slow leak after adjusting my son's valves. I just had to replace the o-ring.

Thanks to everyone who responded, my sons 4 wheeler is back up and running as good as new. After trying several things on my own to get this thing going again, it appears that the Intake vale was out of adjustment to the point that it was not closing all the way. After I adjusted it according to the feedback I received here I could tell a big difference in the compression stroke. I also checked the exhaust valve as well and set it at .004. I put eveything back together and it started right up! I just wamt to thank everyone for their feedback and help.

r//
DD

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Dirt Dobber

Glad to hear that it is up and going.