01 yz125 rebuild please help...

[LIQUIDBALLZ]

i am doing a rebuild on my 01 yz125 i removed the head and the piston shows wear... my question is it normal to see small burn marks on the crank counterweights? the marks are small and only at top dead center..

 

[MikeT]

You will see some discoloration and that is normal. Any grooves in the crank are not normal. I think if the burn marks are heat like (blueish and reddish) marks around the crank pivot, it just shows how hot that area got. I would then just watch my oil ratio and make sure you aren't running too lean. If the burn marks are black and sooty then I don't know why they are there....

 

[LIQUIDBALLZ]

liquidballz.com

:ridethanks..mine are blueish and other than some loss of compression {the reason i tore it down in the first place}i think i just wory too much and dont want to pull this thing apart again to change a crank. my buddys are telling me pretty much what you said.......they drink alot of booze,,,,,so i appriciate the second opionion info.....thanks again ..

 

[wayfastwilly]

heat marks

the blueish heat marks are from the manufacturer heating the counterweights to assemble the crank pin easier. nothing to be worried about, some have them some dont. if your rod bearing got hot enough to blue the crank it wouldnt be turning without a pipe wrench. :)