Posted October 04, 2007 - 09:46 AM
1k mile oil changes
filter every other change
valves checked once
tore her down today valves never moved a .000000001
little skirt wear on the piston
little wear on the wrist pin
cyl. has very little wear
is this good luck or normal?
Posted October 04, 2007 - 03:44 PM
Short(er) pistons usually wear fast. The fact that you got 9,000 miles out of one is a testament to yamaha's engine design.
If the valves never moved, they're probably ok to use in the rebuild. Trouble is you won't know how much longer the nitride coating on the valves will last. Once the coating wears out, the valves don't last very long. How do the seats look? Are they beat up or did they spec out ok? How do the cam lobes and lifters look? What about the valve guides?
If everything in the head checks out decent, just throw a new piston, rings, timing chain, and gaskets in her and let er rip
BTW its not uncommon for the big bore yami motors to go 12K-15K miles
Posted October 05, 2007 - 12:03 PM
i do run klotz 20-50 full synthetic and i think that helps
new siezeco piston chain guides and chain and next week vrooooom