Killed her this weekend. Haven't got it tore apart yet and at least she had the courtesy to die on the trail back instead of in the mountains. Got towed in by my buddys CAT
Anyhow... Think it's just the mag piston, but with 2000 miles do I just replace the bad one or pony up and do all three since I'm already in for head and base gaskets at that point. Looks like I've still got a good month of riding left so wish luck on in-stock parts.
Erik
03 mountain viper
Anyhow... Think it's just the mag piston, but with 2000 miles do I just replace the bad one or pony up and do all three since I'm already in for head and base gaskets at that point. Looks like I've still got a good month of riding left so wish luck on in-stock parts.
Erik
03 mountain viper
I would at least replace the rings on all three while you have it apart. The extra cost is worth it.
yamaholic22
Active member
Why did it burn up? Is it piped? Clogged jet? Bad fuel? I wouldn't touch the other two if nothing happened to them. The rings you have in there right now are seated to the cylinders. If you put new ones in it will have to take the time to break in again, and the rings aren't anywhere near worn out on a yamaha in 2000 miles. Just make sure you inspect everything good, and find out what blew it up in the first place or you will be here again.
It's piped,SLP, variflo
Had a little clutching or gas issue and would only pull 8500, mag side made a little aluminum(3 specks on the electrode/insulator) and was acting funny plugs showed jetting spot on and piston looked good. Just not where it should be little miss at idle and just not pulling the rpm's it should, just backed off for the rest of the day checked/swapped plugs out a couple times. PTO looked washed, center looked fine, and PTO looked gray/black not making metal though.
Gonna tear her down tonight. Local cylinders in stock, hope it just needs honing though.
iso every tank from here on out and EGT's later this summer, but where the hell do put em? Got a dash bag but I guess that'll have to go really want SLP to make a triple version of their single face dual EGT setup.
Had a little clutching or gas issue and would only pull 8500, mag side made a little aluminum(3 specks on the electrode/insulator) and was acting funny plugs showed jetting spot on and piston looked good. Just not where it should be little miss at idle and just not pulling the rpm's it should, just backed off for the rest of the day checked/swapped plugs out a couple times. PTO looked washed, center looked fine, and PTO looked gray/black not making metal though.
Gonna tear her down tonight. Local cylinders in stock, hope it just needs honing though.
iso every tank from here on out and EGT's later this summer, but where the hell do put em? Got a dash bag but I guess that'll have to go really want SLP to make a triple version of their single face dual EGT setup.
yamaholic22
Active member
most guys put the egts either right in front of their gauges, or in their handlebar pad.
SURVEY SAYS it's a season ending injury. The good news is the other two pistons are fine. The bad news is it looks like it ate the crank. The rod looks like it got really damn hot and the rod bearings are crunchy and there is a piece of metal hanging out of the groove. Look like a ring land let go on the exhaust port side so that broke and beat around in the head for a while so thats screwed too probably. And it also melted a hole in the piston on the exhaust side and since the ring stuck there's a nice groove in the jug(expected). AND I cant get the damn pin out of the piston either.
Time for Beer and lots of it.
Now to find someone that wrapped theirs around a tree and has a motor to get rid of or something...