Fuel Mixture

http://dirtrider.net/forums3/showthread.php?t=92818 That was difficult,I must rest now

Normally ppl on a 250 run 40-50:1 although the mixture isnt the real problem your jetting is. U can jet to any mixture but remember that you have to rev high with a 2 stroke. Even a perfectly jetting bike running a low rpms may foul a plug after a while.

Sounds like its rich, spooge is unburnt oil that comes outta the exhaust. I had that problem too, sometime it would bog cause it was so rich. I would say do a plug chop test, this is test to see if your jetting is rich or lean, To test your main jet, get on a long straight and full throttle through all the gears. When it tops out pull the clutch in and kill the engine and coast to a stop, or just let off the gas and brake. Pull out plug to see what it is like using a plug reading guide. Too rich is when its oily and you can foul plugs by this. Go down a size in the main and do the test again. CHeck plug. etc keep doing this till you find that perfect size when the plug is a chocolate brown colour.

Although your main jet may not be the only culprit. Use a jetting guide that you understand to get your jetting sorted. Spanky's jetting guide is the best in my opinion.

Have fun and I hope you get it workin.

Read the oil bottle. Engine temp will greatly effect spooge. Low temps=spooge.