need advise on crank replacement

[hellbertos]

I bought a 01 yz125 recently. It was in decent shape and, of course, I was assured that the thing was well maintained and not abused,.etc. I decided to rip it down and do a top end on it but when I got the cylinder off I noticed heat discoloration on the crank. It is a relatively small spot on the left crank weight, a little smaller than the size of a dime, right next to the connecting rod. The rest of the crank weights look fine and the plastic inserts aren't discolored.

What I'm wondering is if anyone w/ solid experience can tell me, is this a red flag?? Possible senarios which would cause this condition?? Other signs to look for which would contribute?? Also, there doesn't seem to be any play and the bearings seem to spin fine.

I'd hate to end up redoing the top end only to have the crank crap out. Thanx in advance for any quality input.

 

[Rich Rohrich]

What I'm wondering is if anyone w/ solid experience can tell me, is this a red flag?? Possible senarios which would cause this condition??

They all have that discoloration. It comes from the initial manufacturing process and is nothing to worry about. :cool:

 

[hellbertos]

thanx

Rich - thanx for the kwik response and knowledge sharing. I noticed that my ost got moved intot he correct section. Thanx again for helping a newbie. I'll post in the correct section from here on... time to get after that topend...

 

[Rich Rohrich]

Glad to help.