I seized my bike a few weeks ago at my rally (which was phenomenal by the way) going down a massive massive massive(?) hill...WOT. Very stupid, I know, but I just couldn't help it. The thing was a total beast/wheelie machine and still SCREAMED for a V1 Polini. It probably wouldn't have seized if I didn't do this...the thing was pinned at some dumb high RPM as I was going over 65mph (passed my friend on his Harley ha).
Anyways, upon easing off the throttle towards the bottom, I heard a little ting/snap and the thing immediately felt sluggish. Balls. I killed the engine to let it cool off and it wouldn't start back up...zero compression. After my rescue from the vehicle of shame, I pulled the top end and saw this (attached picture).
Snagged a ring on the exhaust port. Also, burnt oil under the piston crown (never had this happen to me before). In another post, Mr. Motzing had suggested that this only occurs due to too much squish or timing...but HE custom squished my head (attached) and I retarded the timing (with a light, don't have a micrometer) a fair amount...like almost in between stock (23* BTDC) and TDC with it slightly closer to the stock mark (so maybe ~15-16*). I used to run stock timing but I wanted more revs and a safer, cooler-running engine.
So what do you think? Is my logic correct here? What should I do differently besides NOT going WOT down the biggest, longest hill on the planet, if anything? Is this cylinder salvageable with some port cleanup and an overbore (cyl has a lot of miles on it)? Are there any piston modifications that I can do to counter this heat? Swain Tech piston coatings? Run only 1 ring? Custom piston? Etc. etc.
Thanks in advance.