94 RM125 fouled plug???

Ok... I'm beatin my head against a freakin wall. I keep fouling my plug, I changed the top end, new ring, gaskets, yada yada yada... I got the proper plug NGK R4118S-9, I've tried BR9ES, and autolite 4062, all fouled. I tried 32:1, 40:1, and 50:1 all fouled. High test fuel, fouled. The only thing I havent done is change the air filter, could the filter make this big a deal??? I checked the reeds too, those are good, no cracks, (that I could see). The only other possibility I could think is, the gasket that goes into the crank from the pipe, (lil rubber O ring) is shot and some oil leaks from there, minimal... Any help????  

If the filter is clogged?  You bet!

Let's start from the beginning.  Let's put in fresh fuel, 32:1 ratio.  A fresh plug (BR8EG, not BR9EG). Let's clean that air filter in soapy water, rinse it, let it air dry, treat it with some foam filter oil, and let that dry for at least 12 hours. Find your air screw - it's brass and it's on the carb toward the airbox/carb junction.  Turn in it carefully until it just barely stops, then turn it out 2 full turns.  WHen you start your bike, give it NO GAS - just turn on the choke and kick it over. Let it idle for a minute before you turn the choke off.  Let it warm up for at least 5 minuted before you take off to ride it (may be cold fouling).. I know it sounds like a lot, but if you follow these steps you should be good.  If it still fouls, then we'll figure out what's wrong in your jetting, because that's the next likely culprit.  
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Ahhh see, I had my air screw out 1.5 turns, possibly to much fuel eh? Also I will try the air filter as I have no idea how long its been since thats been cleaned, and the fuel 32:1... Thanks a bunch bro  

No problem!

Good luck and let us know how it goes...  
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try a smaller main jet. start by removing the carb bowl
drain plug on the bottom of the carb.the main is in up in the bowl. take a socket and remove it the size is on the side of it.go to your dealer and get the next 2 or 3
sizes smaller.start with the next size down.run it for about 30 min.pull the plug it should be a golden brown.if it is black drop the main to the next size.
good luck.  

Thanks guys, I think we're on the right track, pardon the pun. I havent changed the main jet, I did the plug change and cleaned the filter. However it seems as though I'm still getting to much white smoke, ALOT. This leads me to believe I'm still runnin to rich, I backed the air screw out 3 full turns and still a ton of white smoke, I ran for a bit then pulled the plug and it was almost the same color as when I put it in, no charring or anything just looked like the normal plug color outta the box. Any more suggestions, I haven't fouled it yet so I think we're doing good...  

Are you putting out a lot of white spoke at idle, or when you're running it hard? Also, if you're at 3 full turns on the airscrew and it's still rich, you need to go down one size on the pilot jet.

The plug really won't show color until you run it hard, and even then it may take a bit.  
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At reving up theres alot of white smoke when I goose it. If I run it then bring it to idle for like 5-10 secs then rev it, much less smoke, I'm thinking when I run, it burns off the excess carbon, and at idle the carbon builds up??? I know 2 strokes are best WFO. Plug is still hot so hopefully we can keep it running and not foul 'em I'll keep ya posted.

Thanks a bunch for your continued help  

Lots of white smoke = bad crank seal. You ar eppulling crankcase oil into the combustion chamber which is the reason for the white smoke and the fouled plugs.

Check your oil level and see if it is going down after running it for a while.

Replaced the one on my son's cr125, runs like a champ.  The wet side can be replaced without splitting the case.  For my first time, took about 4 hours to take apart and 4 hours to reassemble.

markjtanner@gmail.com  

The plug is staying hot after a few times (so far) I will do the seal though it makes sence. I'm running a hotter plug too BR8EG so.. we'll see. I'll keep you updated. Which side is the wet side, kick side or fuel shut off side? And how much crank fluid do I replace back in the case?

Thanks again!  

I also heard I can put ATF in as crank oil? Is that the same as automatic transmission fluid? And I found the over fill screw I think it's roughly 650 mL's correct??  

650ML sounds right.  You can put ATF (auto tranny fluid), several around here do it, but to be safe I'd just run 10w30 motor oil.. besides, it's usually less expensive  
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So I changed the crank gasket and yet again, what a difference. When I started the bike there was virtually no smoke or a little white smoke. Before it would cloud my garage, it idles much better, the throttle is way more responsive and at about half throttle in like 3rd gear theres no bog as there was before. I think changing the crank gasket worked, I noticed also theres no blow by coming out of where the muffler goes into the case where as before there would always be a trickle of oil coming out. I'm gonna get out this weekend and ride for an extended time on some trails, hope the plug stays hot. I'll let ya know how it goes.
Thanks again to everybody for all your help!!      

The bike was sick this weekend! Worked out great, no problems except for the fact I ran outta fuel once and I thought I killed the plug. Fueled it up and 2nd kick, it fired right up. Ran through 3 tanks of gas no problems. SWEET!
Thanks fellas for all your help!