06 Yzf running wr gearbox -possible-

Desert 450 :banghead: Seeing that the new Yzf450 is not available in my country I was wondering if a wide ratio gearbox will be available for the 06 450. We used to fit the Wr gearbox to the 4 speed 450, but new 450 has 5 gears. They are not the same as wr ratios I suspect, but can the bike be geared beter than 05 4speeder.

Thanx for any recommendations :banghead:

What we do know is that the WR450 5 speed will bolt directly into a YZ450 from '03-'05, but only as a complete transmission.

What we do not know is whether that will be the case with the '06, because the cases have definitely been redesigned to incorporate the oil tank as an internal reservoir and to re-angle the cylinder centerline, but I don't know if the transmission dimensions (shaft centers, shaft length, shift cam location, bearing size, etc.) have been changed.

The rumor is that the new YZ450 five speed is basically the same first four gears as the 4 speed with one more added. That would create a gear set with a wider spread from bottom to top than the YZ426 had, but not as wide as the WR. It would be like having the YZ low gear in a WR, actually, if it's true.

So when you say that the '06 YZ450 is unavailable in South Africa, but then ask if a wide-ratio will be available for it, what exactly do you mean? The sentence seems to disagree with itself.

Not available yet only from end of december. thanx for info. So do you think that it will be possible to gear the yz faster now that an extra gear is available or is the 5 gears just giving different ratios but still in the same min-max output as the 4speed box .(refering to the ratios of the gears) :banghead:

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