Rod bearing going?

I got everything torn down for the big bore kit and noticed the discoloration the crank(see pic). I'm assuming the big end of the rod has seen too much heat. Everything seems to rotate smooth but figued I'd check with you guys.

Sorry but the pic is pretty big.

Crank

Thanks for the help...

[EDIT] Nevermind. In my typical back-asswardness, I did a search of the forums after I took pics, uploaded, and posted only to find out all is well.

Mod's, delete the post if necessary(and to hide my idiocy).

Factory heat treatment. They're like that. Notice that the rod is not discolored at all. No worries.

I've got mine torn down right now too (01 YZ426F) and it has the same discoloration. I was gonna say it's normal but Gray confirmed it. :)

Yep, looks normal to me. If the rod was purple too then I would be concerned.

I just put a brand new crank assembly from yamaha in my 00 426 and it has that same discoloration. That is normal from the factory. :)

Yep, looks normal to me. If the rod was purple too then I would be concerned.

That's a funny sentence there my man. :)

What is a Semi-dry sump?

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