Well while i'm in the middle of solving the fuel pressure issue with my one ZR580 using KC's regulator set up. We were riding the other ZR's when coming off a main trail the wifes sled popped and ran like crap. When she pulled up along side of me the sled died. Pulled plugs found it had fouled out so changed plugs and it would start but would go under power. messed with the wiring harness and all of a sudden the way it went. Rode back towards home another 21 miles and ran flawless. Put it in the garage and went out next morning to check it over. Well it won't start at all. messed with it for a while eventually took it to a buddy's well it took a chunk of the ring and snagged an exhaust port and tore the top of the piston off. YEAH! so i'm now in the rebuild mode again this year. Kind of glad there is no snow right now since i'm down to only one sled. This is becoming a yearly process. Ride one day and put new piston and rings in. I've got an 1990 530 EXT El Tigre LC and Carbed that is just sitting in the garage maybe i should ride that next i haven't had to do any work on it yet. I'm feeling kind of cursed.