5/6 speed in YZ 450?

[Mr Ed]

Hi all,

I'm pretty new here, certainly no Yammaha expert and I have a question:

Is it possible to upgrade the YZ 450 to a 5 or 6 speed gearbox (a-la KTM SX 450 with EXC 6 speed)? I'm up in the air between the CR-F, YZ-F, KTM SX, and perhaps the RM-Z 450 (yeah, like everyone else in the world), and the fact that the Honda is the only 5 speed is seriously weighing my decision. I've spent time on a 426 F, and really enjoyed it. We have a huge amount of desert here, so the gearing is important. I don't really want a WR though....

Thoughts?

Thanks!

[yz_for_me]

With the YZF you're pretty much stuck with the 4 speed tranny. If you want a 5 speed blue bike you have to go with a WR.

[kizzle426]

Or you can get an '02 YZ426F like I did. Trust me, you won't regret it. I've ridden an'05 cr450 and an '03 yz450. I was most impressed with mine, and that's an honest opinion. It was before I bought the 426. LONG LIVE THE YZF!!!

[cowboyona426]

You can put a 5 speed in the YZ 450, but you have to buy a complete WR 450 trans- shift shafts, shift forks, 10 gears, the works. I think it costs about $700 but I haven't heard any snivels from the guys who have done it.

[ovrrdrive]

Yeah, from what I've read, the WR gears are a drop in replacement for the YZ...

[yz_for_me]

With the YZF you're pretty much stuck with the 4 speed tranny. If you want a 5 speed blue bike you have to go with a WR.

I stand corrected. The last I had read on this the WR trans was not a drop in replacement for the YZ, but after further searching I see that it apparently has successfully been done. Cool! Here's the Thread

[grayracer513]

The WR450 5 speed is, in fact, a drop in. You get a lower low, 2,3, and 4 are about the same, and then an "overdrive". There is a possibility that the YFZ450 quad trans may also fit, as I believe the only difference in the crankcases between that and the WR are the hard points for mounting. The quad trans is a closer ratio box. If it worked, I might want to use the mainshaft and low gear from the quad with the balance of the trans from a WR. That would be very much like adding one on top of the existing 4 speed.

No part of the four speed can be used with the swap, not even the forks.

The 426 trans has been used, but according to a long time TT member who did one, it's "a huge PITA" that requires a lot of minor machine work because of internal difference between the 450 and 426.

[yzf450jack]

I put a 5 speed in my 03 450 works like a charm I love it

[the go-devil]

If you're leaning towards the Honda make sure not to overlook the fact that the CRF450R might be a five speed but it is a close ratio tranny with a relatively high 1st and low 5th. How about the CRF450X? Or is that what you were refering to when mentioning a "CRF"?

[the go-devil]

yzf450jack, how much did it cost for the parts to convert to a 5 speed?