- Jul 30, 2007
I have a 2002 CR 250 that I had bought brand new back in 02’. I have always run Honda HP2 synthetic racing oil with 93 octane mixed 32:1. The bike is all stock aside from my silencer. I have ridden this bike for years and NEVER had a problem until recently. The bike runs strong, but has been consistently fouling plugs, even under heavy riding. I am fouling on average about 4 plugs in a 3.5 hour ride. The plugs are wet with a film of gas and oil on them. I have never touched the carb, because I have never had a reason too. When it first started fouling plugs, I replaced the top-end, with a standard size piston and rings and I also replaced the reeds. It ran great but was still fouling plugs just as much. So then I decided to replace the clutch side crank seal. I know that it is possible if the clutch side seal is leaking, that it will draw tranny fluid into the cylinder, thus flooding out the plug. Well, this didn’t fix the issue either. So I then decided to tear apart the carb. There was absolutely nothing visibly wrong with the carburetor. It looked better than new inside, but I still removed all the jets and the choke, making sure everything was clean. I also checked the floats, which were not sticking. I put the carb back together and adjusted the air screw to 1 ½ turns out. (This is the stock setting that I have always used on the bike). I cleaned the airfilter and put a new BR8EG plug in it. Yet it is still fouling 3 or 4 plugs every ride. At this point, I am not sure where to start trouble shooting and my patience is running thin, along with my bank account from buying 4 plugs each ride. I also pulled the stator cover off thinking that maybe the flywheel cover was leaking water into the generator and causing a weak spark, which was causing the plug not to burn hot enough. The stator looks clean and free of corrosion. I haven’t actually taken it apart yet, but I was thinking of cleaning the brushes in hopes to strengthen the spark. Is there any easy way, or any way, to test the stator for malfunction? Also, my exhaust valve (RC Valve) has never been cleaned and could quite possibly be clogged up, but I didn’t think that would cause a rich condition. Any input on this issue would be greatly appreciated.