2003 Yz450f 4th gear

picked up a 03 yz450... slips in 4th gear.. from what I have read its a common thing. my question is, once I tear it apart. do I order oem parts or find a used tranny off ebay? is there an update kit to prevent this or just something that happens?

I also just got a YZ450f 2005 model with the same problem and based on my research on this site and others there is probably a broke tooth off of your 4th gear pinion and or maybe a bent shift fork....might as well crack the cases apart to see first. I'm going to tear into mine next week hopefully. There are numorous gear sets on e-bay ranging from 89-150.00 and the shift fors set runs 35-40.00 range.....Just one gear is 75.00 new. I haven't heard of any unrepairable trannies yet so good luck.

Edited by nohope

Not a broken tooth.  The problem will be wear or damage at the locking lugs ("dogs") on the sides of the gears involved, 3rd and 4th on the main shaft, in this case.  The fork will have been bent by the skipping in/out.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now