atc 200 revs high when started

[smokey]

Today when i started my atc 200 it reved up real high. Any ideas what would cause this. I made sure it had gas to the carb and mesed with the idle screw bud it did not help any.

[ClayW]

The slide in the carb may be varnished up a bit and sticking. Take the cable loose on top of the carb and slide that slide out. Clean it, and down inside the carb, and put it back together. see if that helps. You may also be sucking air some where.

Clay

[Savage99]

My trimoto did that to me....one of the lines on the carb had come off...not sure what it was (not fuel) maybe some sort of air or vacum line but as soon as I noticed it and put it back she ran fine.

I have a question for you....how hard is it to pull your motor over to start it with the pull starter? I just went through my engine (it's still on the floor) and it seems to be real hard to pull now.

Mark.

[Savage99]

Funny thing this post came up because I just got my 1981 atc200 started this evening and the same thing happened to me. I ran some carb cleaner through it, checked the air and fuel lines and no help. When it revs it revs at top speed and there is no throttle left....I guess we are in the same boat. Any help out there?

[Savage99]

Could this be happening if I am getting a slight air leak in the top end, like if a gasket is not sealing properly? Just an idea and it is a little moist around the cylinder gasket. If I take it apart can I use a little gasket seal there? It is one of those metal gaskets that are layered and I wasn't sure whether you could use that stuff on those type of gaskets. Thanks.

[smokey]

Funny thing this post came up because I just got my 1981 atc200 started this evening and the same thing happened to me. I ran some carb cleaner through it, checked the air and fuel lines and no help. When it revs it revs at top speed and there is no throttle left....I guess we are in the same boat. Any help out there?

yep thats what mine does, about a month ago i went through the top end and put in new pistion rings.

[200xkwit]

my 200x did the same thing yesterday. i just put a new top end in it and i used a new metal gasket but when i tighten the head down i didnt tightin it enough so it started to leak and still slightly leaks. so eveyone agrees this is the cause for it?

[AirManCam]

It's either a leak in the top end, or your floats could be sticking.

[Savage99]

I figured it out with a lttle help...I had the 'piston' on the top of the carb (attached to the throttle cable) in backwards. Turned it around a the problems solved. Now onto other problems...when it starts the engine revs fine for a while then speeds up and slows down and then backfires slightly and then stalls. I think it is either a carb problem or a timing issue. Any ideas?

Mark.