'03 450 and later clutch into '02 426?

[pscook]

Like it says in the title, can I install an '03 450 and later clutch into '02 426? I have read in other threads that the '03 has one extra plate and you only need to space out the cover (and use the 450 push rod), but do the gears all line up? I would assume that if the crank, idler, clutch and kicker are in the same place, then the basket should drop right in, correct?

I guess that this one is for you, Gray. What limitations would I have with this application?

[grayracer513]

Never heard of anyone doing it. Why does the '02 clutch need improving?

[pscook]

Never heard of anyone doing it. Why does the '02 clutch need improving?

Not improving, replacing. I found a good deal on an '03 slipper clutch, and I read that the '03 would drop in with minor mods to the cover spacing and push rod. Do you know if the cases locate the crank and other bits and pieces any differently between the 450 and 426? I heard about a primary gear change in later years, when did that come into play?

[pscook]

Oh, and what's the difference between the WR450 and YZ450 clutch basket "Primary Driven Gear Hub" (according to Yamaha parts fiche)? YZ is 5TA-16150-10-00 and the WR is 5TA-16150-11-00. The '02 has no difference in part number between YZ and WR, they both have 5JG-16150-10-00, which is suspiciously close to the '03 YZ clutch number.

[grayracer513]

I don't imagine that the complete clutch basket will work, since the primary ratios are different between the 426 and early 450. '05 had yet another ratio change.

The 450 boss is different, most likely in order to accommodate the extra plates. The pressure plates are the same. Like I say, I've never tried it, so I don't know it will play out.

[pscook]

All right, sounds like some of my investigative information is a bit askew. I have been informed that this clutch will fit the 426 as it uses the stock basket, but provides the inner basket and cover plate. It's a good enough price that I might be able to move it if it doesn't fit.

[pscook]

Doesn't matter now, the seller sold it out from underneath me. [rant] If you say the deal and price is good until "whenever", I kind of expect a little warning before you sell it to someone else. Also, if you send me a number of emails rife with typos, don't expect me to believe that you aren't from Nigeria (or other scam locations)[/rant]. Would have been a cool project, nonetheless.

So, who bought it?

[pscook]

I don't imagine that the complete clutch basket will work, since the primary ratios are different between the 426 and early 450. '05 had yet another ratio change.

The 450 boss is different, most likely in order to accommodate the extra plates. The pressure plates are the same. Like I say, I've never tried it, so I don't know it will play out.

Okay, here's a crazy idea. If I were to replcae the 426 basket with a 450 basket, knowing that the primary ratio changed from the 450 on, I would need to replace the crank gear, the clutch basket, the oil pump drive gear, the idler between the kicker and the clutch, and the kick shaft gear, correct? I'm saying "if", because I 99% am not going to do it, but if I did, all of the relevant gears would need to be replaced to accomodate the new clutch basket. Oh, and the trans gears as well, or at least a new sprocket combo would be needed (not that 13-16 up front and 40-47 out back isn't a big enough selection).

But, with enough money and time, anything is possible, right? Like the infinite monkeys with typewriters eventually coming up with Shakespeare, or something like that. Of course, in my case it would be 10 monkeys, 10 minutes.

[grayracer513]

All that stuff may not interchange. But you might try the '03 clutch plates to see if they fit the '02 basket. Then, you may be able to swap in the partial clutch. It would be your experiment unless someone else speaks up.

Personally, I'd as soon buy one that fit, or work with a later bike.

Also, be aware that there are two kinds of "slipper" clutches, the Rekluse type auto-clutch, and the back-torque limiting type that engage in the normal manual manner, but slip slightly on hard downshifts.

[pscook]

Also, be aware that there are two kinds of "slipper" clutches, the Rekluse type auto-clutch, and the back-torque limiting type that engage in the normal manual manner, but slip slightly on hard downshifts.

Actually, the Rekluse is not a "slipper clutch" (although it provides a facsimile of functions) but rather an "auto-clutch." But you knew that. And there are two other types of slipper clutches (that I know of), the Adler APTC helix clutch and the STM "ramp type" slipper clutch. I think that STM uses the same technology as Yoyodyne. Pretty simple yet effective approaches. And my application will be Supermoto, otherwise I would be all over the Rekluse since that seems like the bees knees for trail riding (and other non-asphalt stuff).

I will let you all know how it turns out.

[grayracer513]

But you knew that.

I said that.

[keegan1014]

I put a rekluse on my 426 and aint lookin back