200m Hard on Plugs, But Dosen't Seem Rich

[Gearheadtom]

I have a 1985 200m with a 200e motor, only difference is that the 200e has high and low range. It seems to go through plugs very quickly, one almost every ride. I was told it did this because the engine in running rich, but if I suddenly put the engine to WOT it dies, like a lean fuel mixture. Is the problem to rich of a fuel mixture or somthing else? Also it dosen't burn any oil, it had new rings not to long ago.

[300rman]

my cousin's big red would eat plugs one every 20 minutes or so. wasnt running rich, CDI was fine.

after a top end rebuild (piston, rings, valves. etc) it stopped doing it. but it never smoked a lick, and had good compression and ran great.

still dont know why that fixed it.

[leokendall]

try a diff brand of plugs.
also move the spark advance a tad, and i mean a tad one way or the other.

[gravelyman]

the air filter may be clogged or the choke could not be working properly. or your bike's name might be obama and that would make it a P.O.S :-)

[Gearheadtom]

I did run NGK plugs in it, but they seemed a litle worse and were more exspensive, so I have been running Champions and they seem a bit better and are cheaper. Also I have heard of using a hotter plug to prevent fouling, would this help, and if it does what plug should I use?

[oscarmayer]

could be runnign lean on the top end.

[MTS]

Check your valves ;)

[Yamada]

Check your valves ;)

Valve clearance, bent valves or what!!!
My big red was fouling plug and it was due to a blown head gasket.
My ytm-225 also foul plug but still can't see the reason. I do know that the carb was dirty, maybe I will take it apart again.

[Gearheadtom]

The head gasket seems fine. Has lots of compresion, but misses a bit if I give it a bit of throttle, and gets worse when the pkug gets worse. I will check the valve gap tommorow if it is not raining, what is the valve gap? It is the same on the 200e and the 200m isn't it?

[Dirtcrasher]

Take a compression test. You can get a decent tester for about 30$ and you will use it forever.......

Then pour a tablespoon of oil in the plug hole and do another compression test.

If the compression increases, the rings are bad. If it stays the same, then it is a valve problem. Oil will temporarily seal the rings, but nothing can seal a unadjusted, bent valve or bad valve seat.

One way or the other, it seems that oil is making it's way into your combustion chamber. Gotsa finger it owt!!!!!!!!! :lol:

[Gearheadtom]

I know the compression is good. I can tell when I pull the engine over by the cord. I hasn't been run a lot since the rings have been replaced. I does burn a bit of oil when I first start it, but that is oil leaking by the valves. I think the problem is my gas. When I first got my trike the gas was orange, rust in it from the tank. I rinsed it out a couple times with fresh gas, but there still is some rust. Would this be the problem? If so, how should I get rid of the rust?