Jump to content

how much change 01 wr426 tranny in 01 yz426

Recommended Posts

Well guys I'm needing help again with the transmission on my 01 yz426 has 2 hours on since full rebuild apart from tranny. I had trouble with common 5th gear slight slipping so adjusted clutch checked out fine not the cause. So i managed to source 01 wr426 donor motor with blown top end for real cheap. I know this has been asked over and over again [ I've read the lot over and over for few month now] but i now have full wr426 transmission and my head is spinning looking for previous threads i read awhile ago so thought maybe you guys would help. Gray racer who has helped me many times in past any help greatly appreciated. Can i mix the transmissions or do i need to use 1 or the other? I'm in UK and the bike will be road registered used 80% on tarmac then 20% off road trails etc. I have split the wr motor and transmission looks ok apart from pics I've posted here any advice on if these should be replaced? the selector fork is 100% scrap and will replace all 3 for piece of mind. I will split the yz and post pics of that tranny for scrutiny and help. Id rather put the cash into it now and last awhile then waiting and costing more parts etc.

2017-04-28 18.28.57.png

2017-04-28 18.28.02.png

2017-04-28 18.30.00.png

2017-04-28 18.31.01.png

2017-04-28 18.35.08.png

20170428_191355.jpg

Share this post


Link to post
Share on other sites

Bad news first: I don't like the looks of any of those gears.  They're pretty beat up.

You can mix the transmission ratios, but don't get too goofy with it and create a huge gap.  I liked the YZF 1-2-3 with the WRF 4-5 quite a bit.  Another sort of road racer-like setup I've never tried is a WRF 1-2 with the YZF 3-4-5 and high overall gearing.

  • Like 1

Share this post


Link to post
Share on other sites

The big wrf's I have been on which have been converted to road legal seemed really at home with higher than stock gearing and the full wr gear set so that cruising rpm could be kept down.   For a dirt bike with the large engine that was going to get on the track once in awhile,  I think 123 from the close ratio set would be good for me,  and if I was going single tracking I could drop a tooth on the front.  It is a nice choice to be in,  but like Gray,  I would be putting different gears in than what I am seeing,  and that fork has to go. 

Share this post


Link to post
Share on other sites

Thanks for confirming the gears are shot in pics. I only loaded pics of one's I thought were no good. I will load rest pics of the tranny for opinions on them ones and also when get to splitting the yzf will need opinions on that also if yous would. Grayracer did you have that yzf 1.2.3 and wrf 4.5 personally? Thanks

Share this post


Link to post
Share on other sites

Yous talk of overall gearing and dropping tooth off the front. I have access to good mate who is metal engineer and will have no problem making me sprockets for front and rear. He made my front oversized rotor for beer money so that's not problem. Any recommendations to teeth? Currently stock front and have new 44 rear (never rode with it yet).

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×