I am in the process of rebuilding a lot of stuff on my '99 SX 600 triple. I had the reed cages out to put new reeds in so I looked the crank and bottom of the pistons over. On the mag side of each connecting rod bearing the crank has a blue hue/color to it like it was overheated. Is this something that happens when the crank is assembled or did it get too hot during use? The sled has about 8,800 miles on it and I have never opened the engine other than to put a thinner Cometic head gasket in it. I use Klotz oil and have the oil pump backed off a little ways from stock. Did the air box and silencer mods also. Hope this is enough info for you to evaluate the potential problem. If it is a problem then the motor is going to have to come out and be gone through.
Mills
Mills
taylzee
New member
In my expereince..they are all like that. I believe it is from when they were heated for assembly.
Boondocker-1
New member
That is normal.
extreme4max4rules
New member
thats normal for yamaha they are heat treated for long lasting to give them a harding temper
extreme4max4rules
New member
thats normal for yamaha they are heat treated for long lasting to give them a harding temper just my 2 cents u got that many miles put new pistons and re ring just to save ur self any possible cracked pistons that could come apart and cause u a lot of damage. Al Larson