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2001 rm125 rebuild questions.

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Hi guys got a few questions before I dive into a little project. I have some mechanical experience with cars, and working on my yz125 but aside from common service and topend rebuilds I've never dived into these dirt bike engines as far as the bottom end goes. So here's what I'm looking at, my brother in law has an 01 rm125 that as far as body and frame is almost perfect condition. He bought the bike a little over a decade ago and siezed the engine a year or so after he got it he believes from oil starvation. I haven't gotten the engine yet but it's all split open and disassembled. He wants to get into woods riding with me and I told him I'd take a look at it and see what I can do. So here's the questions, if the crank is toast what are my best options and what crank should I be looking for (I've heard to avoid the wiesco cranks)? I figured I'd send the cylinder off to millenium for a replate. Is there anything else I should be doing or buying (telling him to buy). Any reassembly tips? I appreciate it greatly guys, this is by far one of the best dirtbike communities out there!

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Everyone says stay away from weisco but I seen to put more of them in than any other lol just did a cr125 and yz85  last week both weisco and have a ktm 150 coming with weisco kit. Put so many of them in and rarely hear of any problems.  Use food pre mix 32:1 and use Belray foam filter oil and they last:thumbsup: but up to you man definitely . When you have that engine split inspect the shiftdrum guids for wear. Done many of that era rms stuck in gear all cause of shift drum

Edited by Motox367
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Yeah that's what I keep reading. I should have it all at my place this weekend. If he's lucky the crank will be able to be reconditioned. I'm guessing there's a slim to none chance that the crank would be in usable shape after a heat seize? I know this will be obvious once I have it in my hands. 

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1 hour ago, Renegade90 said:

Yeah that's what I keep reading. I should have it all at my place this weekend. If he's lucky the crank will be able to be reconditioned. I'm guessing there's a slim to none chance that the crank would be in usable shape after a heat seize? I know this will be obvious once I have it in my hands. 

As Long as the thrust washers aren't chewed off or seals wore grove in flywheel side it be ok to rebiuld  But if one thrust waser is chewed up that half is no good 

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