Clutch spring free length

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dgerst
Cucciolo - the Lil Pup
Posts: 11
Joined: Fri May 18, 2007 7:15 pm
Location: KS USA

Clutch spring free length

Post by dgerst » Tue Oct 08, 2013 12:32 pm

My Darmah's springs are 26mm. The manual indicates 28.9 minimum. Guzzino lists two different lengths, 27 and 30. Are these for different models? My clutch screws are not real tight when in tighten them. Thanks!

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Craig in France
Cagiva Indiana
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Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Re: Clutch spring free length

Post by Craig in France » Thu Oct 10, 2013 9:12 am

dgerst wrote:My Darmah's springs are 26mm. The manual indicates 28.9 minimum. Guzzino lists two different lengths, 27 and 30. Are these for different models? My clutch screws are not real tight when in tighten them. Thanks!
Some (... but not all ;) )of the answer can be found in the part numbers (as set out on Guzzino’s site, but not explained there).

Let me quote this from the site:
“Part # 0480 16 555 is 27mm long and part # 0400 16 550 is 30mm long.”

Explanation:
1. The springs fitted to the early Dramahs were the 0400 16 550 springs, i.e. 30mm long. Hence the minimum length given in the workshop manual of 28.9mm.

However, with these springs, the clutch can slip. The common fix at the time was to fit the shorter 0480 springs. These springs were first fitted to the 450 and are often referred to as such.

2. Now, according to the Darmah parts book, from 1980 on Ducati fitted these ‘450’ springs as standard too. However, irritatingly, the July 1980 workshop manual still gives the old minimum length of 28.9mm - I can only assume that it simply wasn’t updated to reflect the change.

3. Next: in 1981 (according to Ian Fallon) both the clutch basket and the springs were changed. This - again according to Ian - starts with engine number 905168. However, to the best of my knowledge, Ducati didn’t re-issue the parts book for the Darmah, so I can’t confirm this. But Ian is normally right - I suspect he’s seen a factory update bulletin.

I don’t know what length these new springs were. But Ian does point out that the screws were longer at 16mm. Prior to that, they were 10mm. So if you've got the long screws, you will certainly need the long springs. But if you've got short screws, you could go for the short springs.

But in any event: yes, they must be tight!

HTH

Craig

dgerst
Cucciolo - the Lil Pup
Posts: 11
Joined: Fri May 18, 2007 7:15 pm
Location: KS USA

Re: Clutch spring free length

Post by dgerst » Thu Oct 10, 2013 9:56 am

Thanks so much for the info. Much appreciated!

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