Garage Project 450 slipper clutch on 400

Is there anyway to make the 450 clutch assembly work on the old 400 motor? I have a slipper clutch for a 450 and am wondering if anyone has tried to make this swap before.

I seriously doubt that there is room for the 450 clutch in the case.

I just installed a 450 Rekluse in a 426 clutch basket. I was told that the late 426 and early YZ450 ('03-'04) and '03-'06 WR450 use the same pressure plate, so if you need to change out just the pressure plate to make it work you should be covered. I had also heard that the STM clutch for '03-'04 YZ and '03-'06 WR will fit in the 426, but this was from a guy trying to sell it to me. Don't know for sure. I think that there is an upgrade for the grabby clutch on early 400-426 models to use the '01-'02 426 clutch in its entirety, so you might get away with swapping in the 426 basket and using the 450 pressure plate. If you need more room under the clutch cover order a gasket from Rekluse for the 426 (assuming the 400 and 426 use the same cover) as it's .2" thick (~5mm).

If you have it, try it. What's the worst that can happen? :bonk: The 450 used one more plate set than the 426, I can't speak to the 400, but take that into account when measuring your gap. If you don't want to experiment, send it up to me and I'll check it out free of charge. I'm good like that.

I just installed a 450 Rekluse in a 426 clutch basket. ...

If you have it, try it. What's the worst that can happen? :bonk: The 450 used one more plate set than the 426, I can't speak to the 400, but take that into account when measuring your gap.

The 400 clutch is a significantly smaller O.D. than the later two models.
The 400 clutch is a significantly smaller O.D. than the later two models.

Will the 426 basket fit into a 400? Maybe the clutch upgrade is for the '00 426, not the 400. Maybe our OP should send me the slipper so that I can test it, and let him know how it works. It would take a year or two, but like I said before, I would make that sacrifice for a fellow TT'r. I'm such a big help!

Will the 426 basket fit into a 400? Maybe the clutch upgrade is for the '00 426, not the 400.
That's my point; that there may not be enough space available for the basket at all.

And yes, the '01 clutch upgrade is for the '00 models.

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