Changing yz426 tranny gears, more enduro friendly

i suggested it a couple of years ago. i'm told the cogs are swoppable. all you've got to do is sort out which gears are part of the shaft.

Taffy

There is no separate first gear on the main shaft (pinion gear), it is integral to the main shaft. So you would need to buy a WR main shaft and WR first wheel gear (or first countershaft gear).

I’ve considered changing some of my YZ gears for WR but never went through with it.

But if I were changing first I would do second as well, especially if you have a 426 because at that point your gear to gear changes will be very close to the WR until you shift into fifth. Third and fourth gears in the WR are within 3% percent of YZ 426 gears, the former shorter and the latter taller.

That is just my opinion, but keep in mind that WR first gear to YZ 426 second would be about a 40% jump up in gearing. Just seems like a lot to me but if you only use first for crawling or going down steep hills then why not. I know that tight stuff on my YZ is sure hard on brakes and clutches, even w/ a 13 tooth counter sprocket.

I don’t know what the YZ 400 ratios are, but I’m pretty sure that first and second are a bit taller on the 426. The primary ratio is the same for WRs and YZs (62/21 I think).

Hope this helps.

It all helps! I can take it apart and put her back together. But I need help picking the right set up. I'll keep listening and learning!

I'm in the middle of rebuilding my YZ 400 now, and am using WR 1st, 2nd and 3rd. Parts are on backorder for another week. I always had trouble with first being too tall, this should do the trick.

THe problem is, you will have to change out ALL gears, and convert the YZ box to all WR ratios. The cluster gear is different in the 2 bikes, and the speed gears are not interchangable between the 2 clusters. I personally think it would be worth it to change the YZ ratios to WR ratios, because of the 1st gear, and the change in top speed. I do believe it would be quite expensive, however. Sorry for the bad news!!

Dave

To change first from yz gearing to wr first gear.

Anyone have experience changing first? or maybe

5th also? Any input would help. Thanks.

.

Winder till she stinks and grab another one

somebody once put up a yam discount parts dealers web here. it had exploded views of the boix and i think it worked out at $300 for all the right bits. over a year ago now and too many beers.

Taffy

Originally posted by Dave VanBrocklin:

THe problem is, you will have to change out ALL gears, and convert the YZ box to all WR ratios. The cluster gear is different in the 2 bikes, and the speed gears are not interchangable between the 2 clusters. I personally think it would be worth it to change the YZ ratios to WR ratios, because of the 1st gear, and the change in top speed. I do believe it would be quite expensive, however. Sorry for the bad news!!

Dave

A little more info here Dave? What is a cluster gear, and what is a speed gear? Boy am I bummed, I've been waiting for trans parts on backorder for three weeks, and they will not work :) . I know the main axle is different, as it has first gear machined into it, but the drive axle is the same.

Dave, I just ordered first, second and 5th as I

understand 3rd and forth are very close to wr

gearing. I hope your wrong on the cluster gear

theory. Is it theory? or do you know?

Mechanic in waiting!

Originally posted by Dave VanBrocklin:

Sorry for the bad news!!

Dave

That is news to me.

What the heck is a gear cluster, and which gears are the speed gears???

“The speed gears are not interchangeable between the 2 clusters.” Huh??

So I guess the speed gears are INSIDE the cluster. I am not familiar with your terminology Dave.

I’ve thought about this a lot and I don’t see why you could not just change out a few gears. As long as you change the wheel and pinion gears what is there to prevent this from working?

Whatever it is, I don’t see it.

If you are going to bring down Scotti’s dream of WR gears in his YZ at least be a little more specific.

Montclair Yamaha Does the whole tranny for about $440.00. I'm putting one in now during my 10,000 overhaul. From what Ive been told and led to beleive that the whole tranny must be replaced! The toll free phone number for Montclair Yamaha is 1-877-TY DAVIS. Good luck.

[ February 14, 2002: Message edited by: Itsamre ]

Originally posted by Itsamre:

Montclair Yamaha Does the whole tranny for about $440.00. I'm putting one in now during my 10,000 overhaul. From what Ive been told and led to beleive that the whole tranny must be replaced! The toll free phone number for Montclair Yamaha is 1-877-TY DAVIS. Good luck.

[ February 14, 2002: Message edited by: Itsamre ]

:):D:D

I just picked up what they had...missing 1st and second main gears. Third will not work. It has 4 dogs on one side, the YZ only has 3. Oh well, I'm scrapping the whole idea for now.

itsamre

they surely can be persuaded to put the two sets of clusters side-by-side and have a look see?

ask if you can be there with your verier during their lunch break.

tell em the world awaits

tell em anything!!

Taffy

Hey guys, i have been gone for a while, i am sorry for not being specific enough. I will try to explain. Evry gear has a mate in the trans. If you are changing the number of teeth on one gear, you ahve to change the other also.You basically have input and output gears. You will have to change all the gears in the trans to make it work, not just individual gears(1st, 5th ,etc.)Sorry for the vague description before, and I hope this helps a little.

Dave

Originally posted by Dave VanBrocklin:

Hey guys, i have been gone for a while, i am sorry for not being specific enough. I will try to explain. Evry gear has a mate in the trans. If you are changing the number of teeth on one gear, you ahve to change the other also.You basically have input and output gears. You will have to change all the gears in the trans to make it work, not just individual gears(1st, 5th ,etc.)Sorry for the vague description before, and I hope this helps a little.

Dave

That's just not so . You can change just first, just second, first and second, ect...ect...ect.. You just have to change both the gaers thet make first, second or so on. I have mine done now. I could have done first, second or fifth seperate, but third and fourth had to be done together as the dogs between them were different in the WR and YZ in 98. I did 1st through 4th.

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