I seem to have a loading problem. The motor tends to load up at idle VERY quickly. I really don't even need to let it idle..I can make a full throttle blast and it will smooth out, but if I let off for a turn and get back into it, it stutters a bit and take a sec to clear back out again. It is an 87 LT250 with a new B7ES NGK plug. I am running Golden Spectre at 16 ounces to 5 gallons. Temp outside is around 30 degrees. Could the oil just be too thick for this temperature and keeping me teetering on the edge of a plug foul? SHould I go to a hotter plug? Any other suggestions?

 

sounds to me like you need new rings. Also try a b8es that is the standard plug for that bike. Also use b9es in the winter. Also check the carb could be clogged pilot jet

 

it sounds like you need to rejet your carb for this cooler weather. I normaly run a 20:1 ratio. I may suggest to try running a hotter plug if the problem persists.

Matt

 

I'd put a B8ES or even a B8EVX plug in the bike, and have you ever checked the jetting? The pilot screw should be about 1 1/2 turns out, and make sure it is tight. I have seen them set at 1 1/2 turns, then within 2 minutes of riding the bike is running bad again, loading up and all down low. Use a dab of silicone, or a low low strength thread locker to keep it where you want it. The 1 1/2 turns out is with a 250 main, below 41 degrees and 0-5000 feet, higher the temp is outside the further you unscrew the pilot. You will know when it is right, makes a big difference in the quad. Later

 

Well, I picked up a b9es and tried that. Also, I wondered about the pilot jet screw and checked it...it was about 2 1/2 out. I reset it to two turns, but will try the 1 1/2 turns shortly.
I doubt it is the rings, because the bike really starts nice (second kick when cold in 25-30 degree weather) and runs great when it is cleared out.
I called Eric Gorr and he suggested that it could be a bad trans seal and it may be sucking oil into the crankcase. I'll have to check the fluid, top it off and keep an eye on it. That one would be easy to keep track of...

 

You might also check your jet needle as it appears that your problem is in the part of the band in which that circuit functions. Nominal setting is the 3rd position. If it's in the 4th position, you may be a little fat. On the other hand, if it is in fact in the 3rd position, you might move the needle to the 2nd position in order to lean out the 1/4 to 3/4 throttle part of the band.