Blueing on top of crank.......Normal?

6 replies to this topic
  • thumpinscott

Posted April 23, 2004 - 12:52 PM


Is this a normal find? I am going through the trans and top end, should I replace the rod and bearings as well? Posted Image

  • MN_Kevin

Posted April 23, 2004 - 01:37 PM


blue colour is ABSOLUTYELY NORMAL.

I asked the same thing 2 years ago.

  • thumpinscott

Posted April 23, 2004 - 02:42 PM


Thanks, I saw blue, and was singing the blues thinking that it must have burned up a bearing.

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  • SXP

Posted April 23, 2004 - 03:36 PM


Second Kevin above. Brings back memories - I just completed a complete engine rebuild (top and bottom).

Where in SoCal are you? I'm in HB, and would be happy to lend a hand if you need it.

  • thumpinscott

Posted April 23, 2004 - 04:39 PM


I'm out in the 909, Redlands. If I need a hand I will absolutely get in touch, it's my first 4 stroke rebuild, but seems straight forward.

Not sure what piston to go with, wiseco 95 mm or 97mm, 12.5:1 or 13.5:1. I need to decide soon though.

My 5th gear was skipping so it was time.

  • SXP

Posted April 23, 2004 - 04:50 PM


Call Eric Gorr (see He's a wealth of info and very approachable and patient with answering questions.

  • Hamish

Posted April 23, 2004 - 10:10 PM


the blue is from the heat applied to the crank web during manufacturing where the crabkpin is pressed in. When I did my g/box I didnt do the rod/bearing, but that was due to a lack of $$$. Depends how many hrs the bike has done and how much $$ u want to spend. It's cheaper 2 do it now that it is after it's punched a hole in the cases :)


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