WR tranny in YZ? - revisited

How fast do you want to go! with a 5 speed and 14/51 gearing your about 96mph :excuseme:

I was part of the original Dr Rob trans swap.

It was not a drop in by any means.

Search my posts if you want the whole story.

I am stoked yamaha went back to a 5sp.

On a 03 and up it is a drop in! Absolutely no machine work needed! and still to this day with no problems

:ride::banana::D:foul: :foul: :foul: :foul:

OK I just read the thread 2 times, and the wr to yz and yz to wr , 400, 426, 450, will and won't and swaps directly and wont , and shimmwells this or that...:foul: :foul:

I'm a little confused.LOL :mad: :mad:

I wish to swap a 5 spd wr 450 tranny into a 05/06 yz 450!

Can it be done?

all Yamaha parts?

parts needed?

I live in a relatively isolated part of the Canada... it takes 1-2 weeks to get parts in stock in Canadian Whses... so accurracy would be much appreciated, if I have to $pay$ for sound advise... so be it!

:worthy:

Also will the WR rads bolt in to the YZ450?

Thanks Guys!

:mad:

The '03/'05 WR 5 speed will drop in to an '03/'05 YZ450.

The '03/'05 WR 5 speed will not fit into an '06/'07 YZ450, as the newer YZ trans is some .120"+ wider.

SFO was involved with putting the close ratio 5 speed from a YZ426 into a 450, which he did accomplish, but it was NOT a drop in.

As I said before, your best angle on a wide-ratio for a new 450 is to wait for the '07 WR.

The '03/'05 WR 5 speed will drop in to an '03/'05 YZ450.

The '03/'05 WR 5 speed will not fit into an '06/'07 YZ450, as the newer YZ trans is some .120"+ wider.

SFO was involved with putting the close ratio 5 speed from a YZ426 into a 450, which he did accomplish, but it was NOT a drop in.

As I said before, your best angle on a wide-ratio for a new 450 is to wait for the '07 WR.

Grayracer is correct.

Also, for more ratios the 2st gears will work in the 4st for more options.

To clarify, the two-stroke (250, I assume) gears will fit which 4 stroke trans? The 426, or the WR450?

Late '03 we were building the '04 race motors and Keith Mc' said the 250 gearsets can be used in the 4st.

I din't confirm this but an intrepid gearbox shuffler could investigate it further.

Justa informed guess, I guess.

AMAZING!!!

I was just wondering about this topic ... pop into the forum & there it is!!!

I have a '02 YZ 426 that I want to use for desert racing & would like to make the same swap to the wider-ratio WR transmission.

I've heard something to the effect that the WR transmission has issues failing when mated to the YZ motor...? Doesn't sound right to me, but then again, I don't know much about the differences between the two bikes.

Is this list below everything I'd need to order to make the swap? What about circlips, washers, etc...?

Thats an EXCELLENT link Grayracer! Everone who owns a Yamaha should save that link to their "favorites"

So here it is... YZ426-WR426 transmission swap:

#5BF-17411-10-00 Axle, Main

#5BF-17151-00-00 Gear, 5th Pinion

#5BF-17131-20-00 Gear, 3rd Pinion

#5BF-17141-20-00 Gear, 4th Pinion

#5BF-17121-00-00 Gear, 2nd Pinion

#5BF-17211-00-00 Gear, 1st Wheel

#5BF-17251-00-00 Gear, 5th Wheel

#5BF-17231-00-00 Gear, 3rd Wheel

#5BF-17241-00-00 Gear, 4th Wheel

#5BF-17221-00-00 Gear, 2nd Wheel

Is there a shop manual online someplace for the 2002 YZ 426 (or portion thereof) with the procedure for swapping out the gears?

Nice to know what gaskets, etc., will need to be ordered.

is the yfz 450 quad the same as as the WR 450 DIRTBIKE .SO WILL THE QUAD GEARS SWAP TO A 04 YZ 450

is the yfz 450 quad the same as as the WR 450 DIRTBIKE .SO WILL THE QUAD GEARS SWAP TO A 04 YZ 450
It actually is not the same engine. Up until the '05 model, it was a 439, not a 449, and the crankcases are different. From what I can gather, the quad trans is wider, and will not interchange with the 450 4 speed.

well it was a thought seen it on ebay

Any 06/07 YZ450 to WR gear swaps done yet? Just wondering if the parts are a direct drop in like older models.

The '03/'05 WR 5 speed will drop in to an '03/'05 YZ450.

The '03/'05 WR 5 speed will not fit into an '06/'07 YZ450, as the newer YZ trans is some .120"+ wider.

SFO was involved with putting the close ratio 5 speed from a YZ426 into a 450, which he did accomplish, but it was NOT a drop in.

As I said before, your best angle on a wide-ratio for a new 450 is to wait for the '07 WR.

Forgive me, at the time the yz400 has the closest ratio gearset and based on the torque curve that is what was selected.

Sorry for the oversight. :thumbsup:

Any 07 swaps done yet?

I checked into the parts and if I ordered everything the cost is about $660 shipped. How difficult is this things to assemble? Will I need any special types of tools or does this basically just bolt/screw together?

Mike - yep, been done - everything drops right in. Somewhere around $400 in parts

tried to find the link on this forum, but doesn't seem to be working for me right now. Entire list ofpart numbers was given

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