8 plate clutch machining mods

[(F5)]

OK so my RZ keeps slipping as soon as it gets near 90hp, or even 80 in all gears run on the dyno. (Its a 496).

Its always been marginal but left a while and its worse. All the usual FZ600 plates, new steels, 6 heavy springs (and arm on engine extended 8mm so its not too heavy. Belray oil.

I've extra plated clutches before, but this isn't the most obvious.

I'm thinking XT600 middle plates might be thinner but that's unconfirmed. I can't skim down the steels as they are only 1.15mm.

You can take some out of the pressure plate, but the basket fingers are too short for last friction. If you take the washer behind the inner out as a test the inner doesn't seem to go in as far as if you just lay the inner in the basket with no washer. I'm assuming you machine the back of the inner to recess the washer say 1.5mm.

But there must be more to it. Anyone done this? I kinda need to do this myself as nz is a bit too far to be sending it off.

I have a mate who was a bike breaker and has some of his old stuff, so might try dig through and see if some other model can be modified to fit. But I'd have to be lucky

[RuZty]

The FZR1000 used the same steel plates and the wider friction plates we all use, but had one extra disc. Maybe investigate if that hub would make a better starting point. Clutch cover clearance might be an issue. Norbo sells custom clutch covers to take a centrifugal lockup unit as an option. There must be something in the Banshee aftermarket, they do this stuff all the time, but I appreciate wanting to do it yourself rather than dole out a bucket of cash.

[(F5)]

Hmm inner is restricted by the spline. If I machine 1.6 off the back to recess the washer the basket must move in further. It will need a washer on the other side under the lock washer.

Also the bottom fibre needs the edges of the tabs filed so it doesn't get restricted by the curves of the fingers (don't want to file those straight as stress raiser).

Well all that leaves the top friction 1 mm hanging out of the fingers. There's potentially quite a bit of throw when you pull the lever. I feel like Ineed more safety.

One way would be to laser cut new steels out of 0.9. But tthat's pretty weedy for such power .

The pressure plate needs say 2mm out of it to engage in the inner.

What am Imissing?

[(F5)]

Hey cool. Yeah will try the FZR range to see if there is some serendipity. Mate has FZR400 bits. They were 8 plate but spline hole looks enormous. New bush might sort that.

RZ cover has 3 bumps that couldbe ground a llittle if I need space

[justind97]

Why not just get s lock out clutch? 400us ish

[slinger]

Yes you can do it, and it works well. I did a thread on here somewhere must be 6-7 years ago, only used two Tz springs so it still had a stock feel.

Found it viewtopic.php?f=1&t=4950&hilit=8+plate+clutch&start=0" onclick="window.open(this.href);return false;

[(F5)]

Hey gee thanks Slinger. Hmm, so you've gone deeper still, so did you take some off the back of the inner as well?

Thanks for the input.

[MK]

I did a manual for an 8 plate conversion some years ago.
http://www.rd350lc.de/index.php/downloa ... heiben.pdf" onclick="window.open(this.href);return false;

The englisch version is contained in my tuning manual. Infos on rd350.gmxhome.de

Though I'd check first for proper condition of all components like steel plates not bend or too short springs. Also the lever adjustment can cause slipping.

[slinger]

I did mod the inner as well yes, I lowered the whole stack because the new plate was marginal in location. I don't have any drawings or pictures after my computer was trashed by one of theses ransomware virus's. But I think it was very close to what Martin has done !!

[MK]

Maybe I need to mention that there was an EBC DRC43EP (EP = extra plate) Kit for the Banshee around some 10 or 15 years ago. That'd be the easiest way as it contains thinner steel and friction plates in order to keep the pack thickness constant.
So it's a plug & play mod, but the thinner steel plates are somewhat more prone to warping.

Hinson also offers baskets and inner hubs suitable for 8 and more plates (seen up to 11 from other companies).
That's what I currently use after purchasing a straight cut primary and rebuilding the cluch anyway.

[(F5)]

Thanks heaps guys. Struggling to get my tablet to read more than 8 pages of PDFbut iI'll try with laptop. Pictures tell most of story anyhoo.

[MK]

8 pages would be 4 more than the pdf has ....

[Bare]

The 350 (oem) plates are significantly thinner than the FZ ~R6 ones.. Use them to keep stack height from becoming problematic
OEM steels typically live long. Unless something V odd overheated/ warped them? Not that easy in an oil bath.
Also Ferodo sells 'racing' 8 plate friction kits for Fz ~ early R6 fittments for little more coin than 7 plate EBC ones.
So whats' a 496 like ..concrete compactor vibration, lowish rev limit Or both?

[MK]

Is this odd enough:
https://m.youtube.com/watch?v=6LqxsVshIZU" onclick="window.open(this.href);return false;

It was a contest in 1989 where you had to go as slow as possible. The winner got a BMW track day on Nürburgring Nordschleife with Jutta Kleinschmidt as instructor (she participated the Dakar rally a couple of times on BMW bikes and also VW cars)
Easy rules: first one to put the foot down looses. First one over finish line, too.

Note how I got faster and faster on the last meters? The clutch got so hot it wouldn't separate any more and dragged more and more even with the lever fully pulled.
When I wanted to drive home afterwards, the clutch wouldn't separate at all. After disassembly I found all friction and steels completely "glued" together due to that overheating.

[(F5)]

Vibration doesn'tseem an issue to be honest and iI'm sensitive to that.