When to replace a crank??

Barnett117
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Barnett117
Edited Date/Time 9/13/2015 5:59am
Hey guys I had my 06 RM250 lock up recently. I just want to sell the bike without dumping much more money into it. That being said I also want it to be right, not just some grenade. My mechanic said they crank was still in OEM spec. Should it be replaced or what should I do with it?

Also I found some small metal pieces that looked like needle bearing chunks. The mechanic said he couldnt find any broken needle bearings in the motor. Thoughts?

Thank you in advance for the help!
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captmoto
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captmoto 9/10/2015 11:31pm
9/10/2015 11:31pm
Do you trust your mechanic? What shape is the top end in?
poulinaa
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poulinaa 9/11/2015 12:17am
9/11/2015 12:17am
There's nothing wrong with reusing a crank that has been ballenced and has new bearings. Also make sure the pin that connects the two crank halves together and holds onto the connecting rod doesn't show excessive signs of heat or discoloration. Even if it does you can just get a new one pressed in and be on your way...you'll have to do that anyway to put a new connecting rod/rod bearings in.
Barnett117
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Barnett117 9/11/2015 8:05am
9/11/2015 8:05am
captmoto wrote:
Do you trust your mechanic? What shape is the top end in?
The top end is junk. Will need to send the cylinder off and replace the piston.
mxtech1
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mxtech1 9/11/2015 9:13am
9/11/2015 9:13am
If the crank measures withing OEM clearances, it should be fine to reuse. If you want some piece of mind, order a new main bearing and have the crank rebuilt. Much cheaper than buying a whole new crank.


Did the mechanic split the cases? He needs to if you found chunks of anything in the bottom end.

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Barnett117
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Barnett117 9/11/2015 9:56am
9/11/2015 9:56am
I was going to order the Wrench Rabbit top and bottom kit for $390. Would it be cheaper to just do the kit or so piece it back together?
jsmx97
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jsmx97 9/11/2015 10:27am
9/11/2015 10:27am
Have the oem crankshaft rebuiilt with a pro x connecting rod.
19673ontree
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19673ontree 9/13/2015 5:59am
9/13/2015 5:59am Edited Date/Time 9/13/2015 5:59am
You cant reuse any of the crank parts like the pin the bearing or the rod , get a kit that has the pin bearing and rod and have it rebuilt , I will be doing crank rebuilding in a few days ive ordered the equiemt to do it right , cost on the labor is $50

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