YZF450 Gearbox problems...........

Hi guys,

Im just wondering if anyone has had any dramas with thier gearboxes on their yzf450's.Recently I went for a ride and tryed clicking it into fourth. On doing this I couldnt get it into gear and then during the ride had drama's getting it into third and fourth, also when giving it a handfull it would jump out into neutral.

Now im not very mechanically minded when it comes to boxes but was told from a friend that it could be a bent fork in the box.

I know that this sounds weird but when I stopped for a brief period with the motor off and then jumped on it again, it seemed ok for a short period then went back to the way it was. I must mention that whilst doing all this there was no noises coming from the box mind you I nursed it back home just incase. I have ridden this bike probably 5 good rides since I have had it and brought it from a dealer. The bike was immaculate and still is and has been well looked after.I know that this has probably got nothing to do with it but before i went on that ride I changed the oil and filter. The new oil that I changed too was a fully synthetic oil Mobil 1 15W-50.The bike was fine when ridden before with the other oil and I never had any dramas, like i said it's probably one of those things and has nothing to do with oil. If anyone has any info on this and this oil would be muchly appreciated.

Congrats to everyone making it back from The Finke Desert race this June.. and too the winners Grabham and the local lads from Alice.......cheers...marty Alice Springs NT Austraila

When you say you had trouble getting it to shift 4th, did the gears grind, and not want to lock in, or what, exactly?

Hey grayracer,

When I tried to put into gear there was no grinding or noises,it basically wouldnt lock in. It's weird when I pulled up for a while and stopped the motor and then jumped on again it seemed ok for a while then had the same trouble with jumping into neutral and wouldnt go into a coulple of the gears being third and fourth. Cheers marty

is your bike an 06 by chance? if so, there is an updated shifter pawl. order the part for an 07. the 06 had bearings in the roller, the 07-08 has a wheel no bearing. i had the same issue on my 06, while shifting up it seems to work fine, then will drop out of gear going back to the next lower gear no warning no grinding. this was especially true in 4th and 5th. there is a thread on here. with pics and part numbers. http://www.thumpertalk.com/forum/showthread.php?p=4922391#post4922391


Hi Ski,

Yes my YZ is an 06 and exactly what you have explained is doing the same as mine. Thanks for the info mate I will check out the thread.

Thanks again marty

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