WRF450 Slipping Out Of 5th Gear?

Jumped on my '03 WR450 Supermoto today and its slipping out of 5th as soon as any throttle is applied. All other gears are fine the clutch dosent seem to be slipping. Was also fine last time i rode it :bonk: I'm guessing the dogs on my 5th gear have worn, that sound about right? I'm no bike mechanic by any means but am an engineer and my bro has replaced worn gears in an R6 before so i'm guessing we should be able to fix it unless theres anything particularly difficult about the job? Is it engine out or can it be done while its still in place?

Also are there any guides kicking about for this job?

Thanks in advance :lol:

Edited by RipGroove99

You'll definately have to pull the engine out of the frame. It's going to require a complete disassembly. It does sound like either the dogs on the gear are gone, or you've got a bent shift shaft. Either way, it's a complete disassembly. I wouldn't say it's terribly difficult to do, but it sure is going to be time consuming! Probably the hardest part is getting all of the shift shafts in the proper sequence, and meshed with the tranny gears, and then installed! Basically, it's a bitch!! A couple of large rubber bands, criss-crossed over the gears and holding the shift shafts will hold the whole assembly together freeing up one of your hands for the install. Then once you get it in place, you just cut the rubber bands and pull them out, leaving everything exactly where it's supposed to be! Maniac

Good tip, thanks!

My experience with this is that slipping out of gear is a combination of worn dogs/slots and shift fork(s). Thoroughly inspect all the dogs and slots of all the gears of the transmission. If there is any dog/slot rounding/gouging at all on a pair of gears, both gears will need replacement. I have foolishly just replaced shift forks in the past and ended up with gears that still slip. The shift fork damage will most likely show up as wear bottom of the "U" shape of the shift fork.

As far as transmission reassembly, take your time, and don't get frustrated. If done properly, the whole thing comes together in a couple of minutes. Maybe faster if you are really good.

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