Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > 999 / 749 > Slipper Clutch Spider Spring

[MARTIN H]

Originally Posted by Gizmo

it was bad Lil, struggled to get up hartside tonight had some interesting moments when the rear wheel caught up with the slip over the crests It'll be that Martin H playing on his way back down the lake on Saturday afternoon, knew I shouldn't have swapped bikes , sorry don't mean it Martin

I had my earplugs in Michael when you gave me your bike and thought you said "See if you can WHEELIE it back to the house" Sorry I now realise you had said "Take it REALLY easy back to the house"

[Felix]

I agree with Jon, here. They should last quite a long time. One clue is how much you need to compress them when you install the centre nut. It should only compress a couple of millimeters, and nowhere near "flat". Also, the spider spring doesn't affect the heaviness of the clutch or clutch slip when accelerating. That's controlled by the standard clutch springs. If the spider spring is worn out, you'd simply get excessive clutch slip when decelerating.

[JPM]

Felix/Jon...

We fitted the slipper a few weeks ago and after discovering the flat spider spring (luckily we had a spare to replace it with and compare) everything has been fine and it was as it should be, I didn't hang around much last night when Gizmo decided to swap the plates but everything was tight but the spring was moving and not pressed firm against the hub???

[Felix]

I am not sure I follow what you are saying. Once the spring is "flat" then obviously it won't assemble correctly. If done correctly, there is no reason the spider spring shouldn't last for ages. I only used one in my 3 years of racing the RS.

The attachment is an excerpt from my race manual pertaining to the factory slipper clutch, including a spider spring min. height check. Most slipper clutches that use a spider spring are very similar.

Well, I can't attach it as the file size limits seem a bit restrictive.

[JPM]

Felix,

When the clutch first went in and all torqued up the hub was loose??? took us a while to figure out (was it the wrong spacer, washers missing etc) but then we removed the spider spring and compared it to a brand new one, it isn't flat but has definitely been squashed down a few mm's thus the spring when in situe wasn't applying enough force to the drum to keep everything locked in place. We replaced the spring with a new one and straight away this cured the issue.

Yesterday when Gizmo was swapping the plates he noticed the spring was moving but everything was tight as expected, seems to me (although like I mentioned ^^ there I didn't hang around) that the spring has done the same and been flattened slightly after some use??

[Felix]

On the 6 post clutches the free height of the spring should be 7.5 mm or greater. On the 999RS 4 post clutches, they increased this a 8 mm minimum.

PM me an email address, JPM, and I'll send you the pdf for the clutch assembly if you want (~800k).

[Gizmo]

I'll strip it later this week and measure, new spring ordered anyway and a new dished plate. Like Jon says I'm fairly sure it was assembled correctly, we took it apart enough times to work out where everything went stack height was correct and it worked perfectly for 2 weeks then started slipping