there has been many attempts at doing this, the problem is, the crankcase is the intake of the motor..A 2 stroke is really a 4 stroke in all reality..its just doing 2 strokes on top of the piston..and 2 under the piston..the crankcase acts as the intake system of a 4 stroke, with the piston being the valve, and the cases being the manifold...someday someone will figure out a reliable way to isolate the crank from the piston(closing the crank off from the bottom of the piston) which will allow almost zero oil for the top end..just enough to keep the piston/cylinders lubed and still have enough case volume to feed the hp level we need from the cc of the motor......but until then..we have to throw oil at them....
technically eric, your sketch is off...not much air volume in the case itself..(the crank throws take up most of that area..the flow goes up the cylinder with the piston..then as the piston comes down it pushes it back up the transfers....(hence the reason a normal carbed/injected motor with injectors pointed into the reeds gets air/fuel(and oil if premixing)into the wrist/rod bearings..and cools the underside of the piston...and why the pro doesnt..the injectors dont inject until the air is pushing up the transfers on the way to the top of the piston...Good thought... but how is the air going to get pumped into the cylinder with the case sealed?
Die hard....I agree up to a point that some of the bearing issues are oil related..(not enough flow)but I also think it has to do with guys clutching a little light...and not that it is light enough to over rev when the track is in the snow...but when they are airing it out...the locals I know who have gotten bearings..all are very agressive riders,all run custom clutching, all air them out regularly and all rev them pretty tight...when combined with low oil flow..I think it is a recipe for disaster... I also think it is imperative on the pro to keep off the gas for a few minutes after stopping..I see a lot of riders fire and go and back hard in the throttle right after a stop..As of late I know two pros that have lost a PTO Rod Bearing this season. Both 2011s. One had 1500 miles and the other had around 900 miles. Both completely stock.
IMO I think they lost these bearings due to the lack of lubrication. I cranked up my Oil pump 3 turns on my 11 and didn't on my 12 yet at the beginning of the season. I was seeing if I was going to have any run-ability issues as far as fouling plugs or throttle response issues with the increased oil injection. So far no issues at all. I will be turning up my pump on my 12 ASAP. I want my motors to last a little longer than that
when you coming up to ride eric? do you guys even get snow down there? bwahahaha...
