just rebult my scrambler ,new piston ,rings and wrist pin.Changed fluids flushed everything. Iput it back together,cant get anyone to tell me how much oil and what kind to use in the counterbalance.Anyways tried a half quart as told by a fellow owner(he was unsure).I started it up and ran ,idled great for about 2 min,fouled a plug??? No biggey. Put in a new plug, started it,30 seconds later started smoking bad and would'nt stay running.It would startup haveing to give it almost full throttle, it would start to die ,hit the gas and it pepped back up, then foul the plug again. I did this for 3 hours ,same results. drained the oil ,opened all the drain plugs ,the inital oil i had put in all came out and also about a teaspoon came out of the plug beside it, (the air box ?on an angle under the starter motor???)it was black oil. The smoke smelled like motor oil ,2 cycle smells different.DAmn thing sounds strong no raping or pinging .Did i use to much oil, seen on here 3.5 ounces..? cant wait to ride it again,perfect weather in ohio deer season:

 

try a search on counterbalance oil ton of topics on it...might help few different awnsers?