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yz 125 crank question

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Ok so just finishing up my first rebuild. It's a 85 yz 125 and while truing the crank, made the mistake of using a steel hammer on it. After installing crank I noticed that one of the webs has a warped spot from hammering. Just about a half inch long spot where it's warped towards the case. Crank is trued to within spec and crank is not rubbing on case but that one spot is about 2 or 3 thousanths or so from touching the case. Most likely will this contact the case at high rpm? Or should I run it?

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It could touch under heat with thermal expansion. Can you post any pics of the area you are talking about? 2 or 3 thou is tight. Yeah the ol brass hammer is a must.

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I sanded the warped edge with 180 grit and got it to about 1/8 inch clearance from case, way better than what it was and cleaned out the cases from debris. What do you think? I have alot invested in this project and don't want to destroy it by something dumb. lol

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Hey Steve. But my first thought was oooooh Fark. Not good. Very high possibility of hitting the case. I see what has happened. When you have hit that it has distorted. Even though the weight of the web has not changed the evenness or general concentricity has and this will lead to vibration. You do have choices from where I sit. 

 

1, Bad repair but achieavibe........Hit it wit a belt sander until it is flat. Can't even believe I said that. Not recommended but may work. 

2, Desassemble and have both webs machined to a flat surface with equal amounts of weight taken off both. 

3, Buy a new crank. 

 

Let me know what you think.

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I will have that Vid ready for you soon. 

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Option #2 sounds good to me. This crank is non existant almost, so by next rebuild I will be thinking about upgrading!

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