Number of clutch plates 1967 250

[Madman]

Quick question. I was given a 1967 250 single.

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The bike was first registered in the UK in 1969 as a new bike. It was last run in 1993.
According to the Mick Walker book "Ducati Singles Restoration" the clutch should have 7 friction plates and 6 plain plates on all 250 models since 1961. I fitted a new clutch kit and found that things were not quite correct. The old clutch only had 6 friction plates and 5 plain plates and that is all that will fit into the basket. If I put the extra one in then the stack is too thick. and the clutch will not release.
Could this be a typo in the book? Perhaps someone has fitted a basket from a different machine, but at the moment I will get it going again with 6 friction plates. What have others found?

[Jon Pegler]

Some of the modern clutch replacement kits include 6 friction plates in conjunction with 5 plain plates, although the plain plates are 2mm thick instead of the original 1mm thick.
This was done to prevent the thin plain plates distorting with heat, something they are prone to doing.
Some Spanish 250 clutch baskets also used the fewer number of plates but these have a different number of teeth on the clutch basket, 63 teeth instead of the Italian 60 tooth basket.
I would think it's unlikely that you have one of the Spanish baskets fitted.
I would check the plate thickness first.

Jon

[Madman]

Thanks Jon, I have just checked and they are all 1mm. Never mind she runs now with one plate less in there. The clutch is very heavy, probably because I fitted new springs too.
Now need to check the gearing is correct. Anyone know what number of teeth should be on the standard sprockets for a '67 NC 250 Mk3?

[Snakeoil]

Total newbie to these. But the parts book I have shows 17/45 for the road models with 18 counter being an option.

regards,
Rob

[Madman]

Thank you Rob. Just checked and mine are 17 front, 44 rear, so close enough.

Bob