Double check your primary chain tension, sounds too tight.
That could be a bit challenging to remove without dropping it onto the shed.
I didn't touch the clutch when I brought the bike out of storage, other than to check the adjustment. The primary drive had drained itself over the years, so the clutch wouldn't have been submerged in oil, but I guess any oil left on the plates when it was parked all those years ago, will still be there. Its stretching my memory, but I did upgrade the clutch plates some time in the late '70s to some that could cope with oil. Would that have been cork plates to bronze plates? The details of the upgrade have gone, unfortunately.
Thanks this is really helpful, it will be Wednesday before I can get back in the garage, but now I know where to start(20M3S/140)
Ok, that narrows it down a lot.
They would probably benefit from a clean, regardless. Maybe invest in a new set of Barnett, etc. friction plates (and perhaps a new clutch centre, see below).
The bronze plates also need cleaning periodically and the clutch centre spines inspected for notching because that can cause clutch drag if perhaps bronze plates have been used with the old unhardened four-pate centre but the hardened centres still wear.
The original clutch would have had four 'postage stamp' friction plates, three plain plates and a 'thick' pressure plate...
Norton Parts Drawings - Genuine Norton Factory Parts - Commando Parts -
Andover Norton Parts are the only Norton spare parts in the market manufactured to original drawings, within the factory-approved tolerances, from the correct materials, and with the correct finish.andover-norton.co.uk
The later 'bronze' plate clutch had five bronze, four plain and a 'thin' pressure plate...
https://andover-norton.co.uk/en/shop-drawing/207/chaincases-chains-sprockets-clutch-alternator
A 1" pivot radius could be ok, (7/8", might not) I can only suggest you back off the clutch pushrod adjustment to 1/3 - 1/2 a turn as mentioned and see if that's an improvement.
That's happened to me as well, lol
Likely that might not be hardened. I would avoid putting bronze plates back in or you will be in same boat. Get some Barnett plates.Following LAB's advice, I stripped the clutch and found that my clutch centre was pretty heavily notched. So looked on AN and they are £103, frustrating, but it needs replacing. So I stripped the clutch and removed the centre, then as I looked at it, it looked familiar, I'd seen something like that in my box of 'unfitted parts'. Had a look through that box, and there it was, a brand new, unused clutch centre! Some time in the 1980s I must have recognised the bike needed a new clutch centre, so I'd bought one, but it never got fitted, until today. So that purchase from about 40 years ago probably cost about £10, but saved me £103 and a couple of days waiting. Amazing
Following LAB's advice, I stripped the clutch and found that my clutch centre was pretty heavily notched. So looked on AN and they are £103, frustrating, but it needs replacing. So I stripped the clutch and removed the centre, then as I looked at it, it looked familiar, I'd seen something like that in my box of 'unfitted parts'. Had a look through that box, and there it was, a brand new, unused clutch centre! Some time in the 1980s I must have recognised the bike needed a new clutch centre, so I'd bought one, but it never got fitted, until today. So that purchase from about 40 years ago probably cost about £10, but saved me £103 and a couple of days waiting. Amazing
I have ordered Barnett plates, placed the order at 23:45 last night, they were shipped at 11:15 this morning, should arrive in the next day or two. Buying Norton parts used to be so difficult, writing letters to a few places to see who had what, then writing back to place an order, with a cheque in the envelope. On-line shopping is so much easier, I love the Internet.
It looks like I had two originals, with cork pads, and two of those solid fibre ones. I don't know why I had odd ones, but I guess its because I could only afford to replace the ones that had the most wear. Money was very tight back thenWere you able to identify the type of friction plates?
Later '4-plate clutch' frictions would have been the "solid fibre" type.
Andover Norton - CLUTCH PLATE (SOLID FIBRE) - 06.1339
CLUTCH PLATE (SOLID FIBRE)andover-norton.co.uk
