My Bike is eating plugs

[Cheb44]

I cant keep my 03 RM250 from fouling plugs.  Last two rides it killed two plugs, at a plug a ride this would get expensive lol.

Anyway I chopped both plugs from my last rides and they both are completely black all the way down.  I am assuming from a rich condition.

My problem is it seems as though I should be jetted right and I am afraid to change to much without some advice.

My current situation is:

32:1 yamalube 2r (switching to Belray)
165 main
45 inter
needle on second clip
and stock slide.

Any relevant mods are just a carb spacer, and a flywheel weight which I don't think would affect much, stock pipe, fmf silencer.

I know this year model is notorious for awful jetting but there has to be a sweet spot.  I know many change to the #7 slide does anyone with experience know if this will really make this big of a difference.  I don't ride in it all the time but I am not putting around either, pretty normal woods/Mx riding.

Also any maintenance items that might cause this?  It has a fresh top end with a brand spanking new cylinder due to a Wiesco Circlip gone awry.  After last rebuild I had discovered the power valve actuating arm stuck open and thought that this was my problem but since fixing all of that its still happening.  Only thing that hasn't been changed in the last rebuild were the reeds and they seemed okay.  Maybe run 40:1?  I hate to change ratio, that seems unnecessary.

Any help would be greatly appreciated.  Thanks guys.

[2005yz250]

What heat range plug are you running? I used to run a br9eg and would foul at least one every time I rode.  After switching to an 8, i am still on the same plug after six months.  Look in your manual and see what heat range plug the factory calls for.  Hope this helps

[ford832]

Mix ratio won't foul your plug.You need to do plug chops with a fresh or reasonably fresh plug at 1/4,1/2,3/4,full throttle at the very least to determine where you are rich and where you may be lean or ok and start leaning out your jetting from there based on your results.

[SachsGS]

Start with the basics -clean airfilter,repacked silencer- and then into the carb.Make sure your float height is within spec.,needle and seat not worn and then move into the jetting.

One trick is to record the jetting specs and then let a carb savvy guy ride your bike,he'll (she'll?) be able to recommend what jetting you'll need to get your bike in the ballpark and stop fouling plugs.

On occasion I've worked on chronic plug foulers where the problem was traced to a failing CDI component or a weeping transmission side crankshaft seal.I recently repaired one bike that had a loose electrical connector and was fouling plugs like crazy.A little squeeze with a pair of pliers and problem solved. 

[ford832]

I recently repaired one bike that had a loose electrical connector and was fouling plugs like crazy.A little squeeze with a pair of pliers and problem solved. 

Motoplat? 
Actually,that's what I'm doing today.A guy with a GasGas300 is coming over home for me to jet it for him.We just had new neighbours move in down the road yesterday so today I'll be doing plug chops up and down past their house.Welcome to the country neighbours!Get used to it.....

[SachsGS]

Yep.1977 Ossa Super Pioneer.