Ducati Sporting Club UK > DesmoDue Race Series > DesmoDue - General Questions and Chat > Slipper clutch

[paynep]

Originally Posted by multi600

Don,t know about the Sigma, one but the standard one is not worth fitting.

Mike

Mike, why do you say that?

[rich-racing.co.uk]

Ian Leah had a sigma slipper in his (my) bike last year. get in touch with the old man!

[fil2]

Originally Posted by paynep

Mike, why do you say that?

better than std clutch or std slipper that comes with the newer models.?

[multi600]

Originally Posted by paynep

Mike, why do you say that?

I thought the idea was that the slipper clutch stopped the back wheel from locking when down shiffting, I found the one (standard Ducati one) fitted to the Multi did not prevent this. Last year when I fitted the rear sets to the Multi I inadvetantly converted it to a race shift patern but did not realise till I was out on track, twice in the race at Castle Combe exiting corners I knocked it down a gear instead of up and the back wheel locked solid

Mike

[paynep]

Originally Posted by multi600

I thought the idea was that the slipper clutch stopped the back wheel from locking when down shiffting, I found the one (standard Ducati one) fitted to the Multi did not prevent this. Last year when I fitted the rear sets to the Multi I inadvetantly converted it to a race shift patern but did not realise till I was out on track, twice in the race at Castle Combe exiting corners I knocked it down a gear instead of up and the back wheel locked solid

Mike

okaaay

[fil2]

Originally Posted by paynep

okaaay

Paul...

Wot slipper have u got fitted .?..the version that comes with the later models or an after market jobby.?

[paynep]

One from a damaged S2R...........which is the same part # as the 620 one, and the one listed in the DP catalogue....

Likewise the 6-speed box, but I'm saving the heads and barrels until 2008 when I go play with the Sport 1000s... ;-)

[the old man]

I ran Sigma slipper clutch in 2006 and can recommend it - I will be running a Sigma clutck in my Thunderbike next year.

Mine was a 5 speed 620SS. The standard clutch has a tendency to grab when coming off the line and I know others have had problems with clutch slip (mine was OK with an extra steel plate in the pack).

The Sigma slipper clutch cured all those problems; it gave smooth take up coming off the line; never slipped (once we'd got the correct spring combinations sorted) and made the bike much more stable on the brakes into the turns - I was a sceptic but ended a convert!

[the old man]

The clutck is a new Sigma development (was a secret till I just blabbed it now!!).

It is based on the standard Sigma device but incorporates some of the ideas Neil Spalding picked up in the MotoGP padocks - specifically it incorporated a set of sun and planet gears, causing the heavier clutch drum to rotate "backwards" emulating the Yamaha MotoGP engine (with its backward rotating crank) and - in theory at least - reducing engine gyroscopic effect.

Having the engine gyroscopic effects opposite to those of the wheels (both rotating forward - usually) reduces the overall gyroscopic effect fely by the chasis and makes the bike more nimble, improves traction and reduces the tendency to wheelie under power.

[MLC Racing]

Slipper clutches eek! My old DLS bike with 58bhp, high bars, and std clutch came 2nd in 2005. Boggy's bike won 2005 without one. Is this not a case of over egging the pudding!!!!