WR450F Engine Rebuild

Ok, so the gear for the kickstart would make a buzzing noise but would go away if I messed with the kick arm. I was riding and didn't realize the bike was in 3rd from stop and stalled the motor. I went to kick start it and the arm had shot forward and it ended up cracking around the kick start gear on the crankcase housing. I have a few questions before starting the rebuild. Just an FYI, I am pretty experienced with tools. I work on cars and airplanes as a hobby, but don't have much experience with bikes.

1) what special tools will I need to disassemble and reassemble the motor?

2) is there any recommended changes while I have the motor broken down?

3) is there kits available for rebuilds and/or is there any shortcuts from removing every bolt and part to get to the crankcase housing?

4) do I need to replace both side crankcase housings (to pair up correctly) or can I buy just the right hand side?

This is for a 2005 WR350F.

Thanks guys!

The only Special tool that I know of that is required is a flywheel puller to be exact. I just machined myself one, but they do have them on ebay. 

I would change the timing chain, check valves and if needed change the valve shims. Check for any deep scratches or scuffs ins the cylinder. Check piston condition, get all new gaskets. Clean the head if there is a lot of carbon buildup. Turn all the the bearings to check for any rough spots, Check the shifter forks and gear condition. 


I am currently rebuilding mine as well. My con-rod/crank bearing went really bad. 


Check my build thread, I have info and pics of my engine tear-down all throughout the thread. 


Buy and OEM service manual and all of your questions will be answered.

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