After destroying my last top end when a piston circlip came lose and chewed into the jug and piston, I started trying to figure out why and came to a possible conclusion.
I haven't noticed any mention of circlip position on the piston on this forum, and didn't think about it before, but it's apparently standard practice to place the circlip opening at either 12 o'clock or 6 o'clock.
If it's in sideways, at high RPMs it can flutter, compress, and jump out of its groove.
Since our circlips have the added mass of the inside prongs that allow you to get purchase with pliers or what have you, that makes even more sense.
So before you lose a top end and have to dig chunks out of the crank case, check those circlips!
I haven't noticed any mention of circlip position on the piston on this forum, and didn't think about it before, but it's apparently standard practice to place the circlip opening at either 12 o'clock or 6 o'clock.
If it's in sideways, at high RPMs it can flutter, compress, and jump out of its groove.
Since our circlips have the added mass of the inside prongs that allow you to get purchase with pliers or what have you, that makes even more sense.
So before you lose a top end and have to dig chunks out of the crank case, check those circlips!
