Re: air coming out of the left side of a 4 stroke motor.
There is one reason and one reason alone as to why any clutch wears out prematurely, slippage. How often do you use the engine power alone from a dead stop and how much riding do you do where the engine isn't running fast enough for the clutch to be fully engaged do you do?
Like scotto- said, there is a FAN under the FAN shroud that blows AIR across the fins to COOL the engine.
Dude, your other engine sized up because you 1st grossly overfilled it with oil then you 2nd ran it with no oil. Do you even know how an engine works?
Straight tubes suck, the beauty is in the bend.