'82 Atc 200 keeps fouling plugs, need info.

[kormos_93]

As the title says, my '82 atc 200 fouls plugs constantly. I cleaned & adjusted the carb & it runs great, has lots of power & doesn't seem to smoke from the exhaust at all. But after a couple of hours of riding it dies & the plug is BLACK, not wet, but Black & stops sparking. I change the plug & away it goes. Any info/advice would be great. Thanks.

(Tried a hotter plug & it lasts a little longer, but the result is the same in the end)

[tri again]

There's another thread just like this just today.
Guess we need an answer.
Have you tried the search key?
service manual?

You say it runs great?
slight Vacuum leak?

I got a 13 dollar spark plug cleaner from h freight just for that reason.
I wonder if your carb jets are stock or someone changed them.

Absolute worst case is new carbs are like 20 bucks and most have really good luck with them.

[yamahonda84]

Did you try changing your plug wire

[kormos_93]

New coil, new CDI, New plug, Tried a carb off an identical trike (know the original owner of that trike (that I borrowed the carb from), & it had a stock carb with the factory jets. Have the same problem even after I put it on my trike. I also tried moving the main needle up & down & adjusting the air/fuel mix screw.

[shortline10]

Your spark prob isnt FAT enough so it fouls the plug . Make sure the pulse generator is gaped correctly and clean the flywheel magnetic area and possibley a new stator if its on the weak side .
A carb rebuild kit prob wouldnt hurt either :lol:

[vonlindheim]

sounds like rings allowing oil to reach the plug. how easy does it pull start. this always tell me when my rings are going bad, because i can start it with one finger on the handle ( not good )

[newfietriker]

could it be something with the air filter?, a fellow here had the same problem with his bike, he took off the air filter, cleaned it all up, same thing, then he looked at the hose and it was clogged full of dirt, cleaned it out and good as new

[muthey]

what size spark plug are you running, a d8ea or a d7ea, they both work the d8ea is a little hotter, with where you are at it might be better to run the d8ea those are the ngk part numbers sorry

[RacerRichie]

should be running the D8ea plug.
do a compression test
what kind of oil are you using?

[kormos_93]

I cleaned the air filter, turns out it was clogged full of mud (causing too rich a mixture and fouling plugs) . It also had an exhaust leak. Compression is a little low but it seems to be a lot better now. Easy fix, I guess I just overlooked the filter. Thanks newfietriker.

[Big-B]

What if you have bought a brand new filter?