the pics make it a bit difficult to diagnose damage or cause...the damage at the intake port makes me wonder if something got thru...any chance you could take the piston off and let us see the upper bushing?
Looks like it could have been the crank or the piston bearings gone bad, allowing the piston to travel further than it was intended to. That might explain some of the mushroomed metal to escape into the ring notches causin the piston hole.
Just a theory!
Doc
dockspa i was thinking the same thing the shavings from the head and piston contact may have done it im just glad this happend right in front of my house cause i was about to take a 10 miles ride in traffic that would have been a Bit$#
i asked dax about there performance exhaust they said the one on the 65 was there performance one it looks the same to me does anyone else no the diffrence
big difference in length of pipe, size of muffler, & sound...so i'm assuming it has some effect, but i can't say good or bad, yet.
after i break-in that 70, i'm going to swap & compare mufflers, but i don't want to distract from this specific review of the 65, so that's for another time and place.