Fouling a lot of spark plugs...

Well I am real new to two strokes. I had my Yz for about three or so months and I am still fouling spark plugs. I ride in trails and sand pits, when they foul I am usally in a tight spot where I just hold in the clutch and manuver myself out of it. (IE:Rocky parts on trails). Is this because I'm not revving it up?

Thanks just let me know if you need specs of my motor, its somewhat worked.:thumbsup:

My first few months i went through 60$ worth of spark plugs, then i started to learn about jetting, coming from an air cooled 4 stroke which never fouled plugs it was all new too me. So find a jetting guide and print it out and memerize it :thumbsup:

Not reving high enough can cause plugs to foul so if your just trial riding without long wide open sections, you can maybe get a hotter plug, br8eg instead of br9eg. this will burn off that excess unburnt oil thus cleaner spark plug.

But try to rev high dont keep it at 1000rpm if you know what i mean, but jet your machine for what your riding style is and you'll be sorted!!!

Hope that helped

Alright thanks, I bought the bike from a guy up in the Catskills, I'm all the way down in NE PA. Do you think the jetting could be different because of the lower elevation?

Totally temperature altitude effects it, I bough my bike from a guy who practically lived on top of a mountain and i live near right at the sea on the coast so when it was up there it worked perfectly the day i brought it down to my house it fouled, those plugs where so wet. Have fun sorting it out its all worth it in the end the power of a properly jetted 2 stroke is better than what pipe can do for u. IS it a 125?

Its a 2003 Yz 134, port and polish v force reeds FMF SST and FMF shortie and a few other things.

My plugs were extreamly wet and completely black when they foul. So you guys should think I should rejet?

Its a 2003 Yz 134, port and polish v force reeds FMF SST and FMF shortie and a few other things.

My plugs were extreamly wet and completely black when they foul. So you guys should think I should rejet?

Without a doubt, rejet now before u waste any more plugs

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