Crank Rebuild

_JOE_

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#1
So the rm250 I sold to my friend this spring is beginning to make a slight growling noise in the bottom end and is starting to smoke a bit more than it used to, so we are going to do crank bearings and seals. It has at least 80 hours on the crank. We did an EG 265 on it about 60 hours ago and it already has a Hot Rod in it. I was wondering if we can just replace the rod when we do the crank bearings and lower end inspection, or if it will need an entire crank. I have never replaced a rod before, but he does have the factory service manual I gave him with the bike. Also anything else to watch for while doing this? Thanks for any advice.
 
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#2
Contact hot rod,they have complete engine kits. A lot of cranks are about impossible to change the rod. All said and done,its not much more for a complete crank!
 

_JOE_

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#3
Would it be a real bad idea to reuse the crank/rod assembly? How hard is it to get the bearings off the crank?
 

_JOE_

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#4
I looked on their website, they don't list a crank. They do list a rod though.
 

_JOE_

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#6
Yeah, i'll call them up. If it comes down to it, I would definately use Eric for the crank rebuild, he did a great job on the cylinder for us. Thanks for the help, and nice new avatar :cool: .
 
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#7
Joe, I just went thru it this spring with my RM. For some reason nobody has rebuilt cranks for RM's. When you tear it down, inspect the crank thoroughly. The rod bearing is checked several ways. Visually inspect the needles thru the split in the bottom of the rod. Spin the crank as you look so you can see all the needles. If there's any signs of damage it will have to be rebuilt/replaced. Next, if there is any detectable up and down play the bearing has to be replaced. If that's good, use a feeler gauge to check the side clearance between the rod and the crank. Lastly, measure the distance the rod moves at the top as you rock it side to side with a dial indicator. All the specs and procedures should be in the manual. If the rod checks out fine, you should mic out the main bearing journals for both size and roundness. On my RM one of the journals was oblong and close to .004" undersize at it's smallest point. That negated getting it rebuilt for me. Prior to discovering that issue I had contacted Eric Gore about rebuilding it. He was too busy but recommended a buddy of his that rebuilt cranks for I $125 including parts... "...my friend Ryan from Finishline Engines offers crank rebuilds with parts for $125. His number is 1-920-382-2897". I ended up finding a NOS Suzuki crank on Fleabay for my bike.