I remember when I was a kid our mini bikes and go carts had centrifugal clutches that were open with a gear on them. Now the clutch and gears are enclosed. It seems to me this would allow for more heat to accumulate. I can understand the safety factor for when things fly apart or explode, but the clutch could have a couple of slots next to the block to allow a little heat dissipation. Also the gears sling the grease out from the gears, so why couldn't there be a couple slots on the sides of the case. Has anybody else ever pondered this.