84 atc 200s stalls out after 20 minutes. must wait to start

[iamlunchbox]

I recently purchased an 84 honda atc 200s. After riding it for about 20-30 minutes the idle slowed and it stalled out. Was riding normally, not heavy, never got out of 3rd gear. Tried pulling and pulling with no luck. Pushed it into the garage and let it sit while I ate dinner. I went back downstairs and checked the spark plug which I installed the day before and it was black around the threads with the tip being white. I pulled the plug back in, pulled the started and it fired right up. Any ideas? I have no clue where to start on this one.

[saleen_n_around]

Does it have a vented gas cap on it that might be clogged? Try riding it with the gas cap not all the way tight, like half turn loose.

[Vealmonkey]

It could be the coil, cdi or wiring. Sometimes old wiring or electronics will build up resistance with heat and just stop working. They will work again once they cool off, but they will quit completely soon.

[Taiser]

Yep what what they said above. Check the carb too, could be a sticky float, although 20 minutes is a long time to run, but something could be causing the float to stick up for a bit and not letting fuel in, could also be a clogged line from the tank to the carb or a bunch of gunk on the petcock tubes in the tank. I'd start by cleaning out the tank, petcock and carb, make sure the tank vent is not plugged and then go to the electrical. After it dies, check the electrical right away and see if you have spark. If you don't it's probably (in order of crapping out), the coil, the CDI then the stator. See where that takes ya, good luck!

[iamlunchbox]

thanks guys. I probably wont get to play with it tonight but will in the next few days and will let you know what I find.

[NewfieBish]

my buddy had an old 200 (M?) and it always done that, and it was the coil, i think it was the magneto coil after, but yeah, i've also heard tell of gascaps on those 200's not venting right as well, but it defenitely is one of those 2

[iamlunchbox]

rode it around today and it looks like its the gas cap. I put the cap on a quarter turn and it ran fine. Turned the cap all the way on about 5-10 minutes later it stalled out.. When i took the cap off you could hear it sucking air as i removed the cap. Anybody know of a place to buy aftermarket or should I break down and go to the honda dealer

[RAGDOLL MX]

check with Mike over at vintagemotorsports.net he usually has what you need, he has hooked me up with a ton of stuff