gear box problem in wr 426

has anyone come across any gearbox problems in their wr 426 ?? as in the dog tooth sytle gears not meeting each other properly and chewwing them out?? i was at my local bike shop today and they said it was very common 4 this to happen??...and to get something done about the gears?? under cut them or something like that ?>? is this true??

as my bike has only done less then 500 km ...i'm a bit worried !!

as a mate's has only done 2,300 km's and it's in for as total gearbox rebuild ..$2,000 bucks australia


I have personally never seen or heard of any iissues with the trans in any way? No one has said anything on this board in over a year that I have been participating.


Unfortunatly i am the bearer of bad news, i have experienced this problem, some of the dogs on some of the gears don't mesh properly and this is what i have found, if third pinion gear doesn't break into two as a result of 2nd and 3rd pinion gear dogs not meshing properly, 5th pinion gear will skip (jump in and out of gear) as a result of the holes inwich #2 shift fork slides between the cases being flogged out, all can be repaired and fairly cheaply, new gears have to have the dogs champhered and the cases can be repaired by a good engineer with a digital mill that can map out the shift fork holes to be able to drill and sleeve #2 shift fork holes, once this has been corrected this problem will never be a problem again, i have some photos somwhere, email me and i will try and send the pics across to you.

Craig i too had the same prob with my YZ 426,, it was jumping out of fifth. I pulled it apart only to find the bevel on the dogs were worn ( no undercut to hold it in gear) also the shift fork was bent, caused from the gear jumping out. I replaced the dogs and shift fork, all ok. It appears that the guy that owned it before me never used the clutch to shift gears. I now use the clutch 99% of the time.

My '01 WR426 started having 5th gear issues after 1400 miles of baja.

It happens.

Fix it and and ride.

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