eats plugs

can some one please tell me what i can do to my bike to keep it from fouling plugs.

1. Most important, do not use gas with oxygenates, usually ethanol. If you arent sure about the gas, go buy race gas, at least for troubleshooting.

2. Jet it right.

3. DO the BK mod.

4. Do not touch the throttle when you start it.

1. Clean your pilot jet.

2. Lean up your pilot circuit or fuel screw.

3. Jet bike top top bottom.

4. Consider blue wire mod.

5. (not very helpful) run hotter CR8E plug

6. Use a proven starting drill. Don't touch throttle when cold until it starts. Don't run on choke longer than necessary. Don't shut down until thoroughly warmed.

Main thing, clean the pilot jet and don't overoil air filter to keep it clean.


the bike is only 2 days old its a 2002. i just did the bk mod but have not been able to try it yet cause i need a new plug. but the bike was stock and still fouled them like crazy. i orderd a white bros full exaust system for it. stock plugs a CR8E. when i did the bk mod i tuned fuel screw in a half of a turn but i dont know if i fixed the problem yet.

I was having the same problems with my 2002. The shop Dropped the needle, turned air fule screw out, adjusted the floats, and put in a hotter plug. So far it seems to have worked. I also did the blue wire mod. I would ask your dealer to do the work, they might feel sorry for you and do it for free. They did for me.

As others have said, you have to make sure you are jetted right, that the gas you are using is OK, and that your float height is set. There are already tons of posts on jetting. Do a search and read them. Then take your carb apart and change things one at a time (move clip up or down, adjust fuel screw in or out, change pilot or main jet) so you can "feel" the effects of your changes...

my jetting is stock so what could be wrong with it.


couple of things

1: Dont put a hotter plug in BAD NEWS BAD Advice

2: Mods need to do some mods.

3: Check everything out first before deciding on Mods

Example is one other post regarding fowled (Ark-A-Doodle Dont)plugs. On advice, get the electrical checked out by the dealer. some have reported bad electrics in the bike.

So with that, if your bike is stock BONE STOCK, no pipe or after market gizmoes.

1: Clean Carb clean air filter real well. Tear carb completely apart make sure all the low speed air vents are opened.

2: Air filter Clean (Very Little oil) enough to just coat the foam "LIGHTLY"

If you have a Pipe on it or ?

1: BK

2: Blue Wire

3: Do Everything in carb clean above

The bike is 2 days old, I hope the carb is not plugged up already.

I would not mod a bike until the 30 day warranty is up because the dealer can blame the mods on the problems that are arising. i.e. bk mod.

thanks guys but i did bk mod with my own adjustments with the bk bolt and it runs awsome starts awsome and have no more fouling of the plug. thanks for every thing guys.

Last Thursday, I hooked up with my friend who has a '02 for a day of practice. As we rested between sessions, we talked about his plug fouling issue. This is his third "F" so he is very familiar with the YZ thumpers. What shocked me was what carb changes he had to make to cure his fouling problem. He went to a 38 pilot, left the main jet stock, went to a one step leaner needle, and went leaner on the needle clip(I don't remember if it was one or two clip positions). It worked. I noticed how well his engine carbuerated and the throttle response was very crisp.

Just posted this under another topic. Applies here too.

I've had your problem now. I was running a 162 main, FHN#3, 35pilot, 1 1/2 turns today. Was trying the lower clip and smaller pilot because I had just fouled a plug last ride. Wanted to be way too lean to prove a point to myself. Anyway, went through a new plug in less than an hour riding intermediate MX. Pulled the plug and it wasn't "sooty" at all. It looked like it had been painted black with a flat enamel. Was pretty evenly colored from the center electrode, center ceramic, bottom electrode, and bottom of threads. Never saw a plug quite like it.

Anyway, I have always run Shell 93 through it. They must have had the seasonal formulation change, because I clearly wasn't rich (and it had lean symptoms on pilot and needle), I only started it twice with no choke and no twist. The only other explanation is fuel. And I still have two gallons in it. I'm taking extra plugs tomorrow to see if it repeats. Oh yeah, CR8E.

can empathize now,


check out the wr post. taffy over there has got the best jetting. everyone who has tried it is happy and can't belive how much better there bike runs. copy what he does and add 10 on the mj. trust me, i did it and it flys.

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