Britstuff
VIP MEMBER
- Joined
- Jan 8, 2021
- Messages
- 139
Hi:
1974 MkII 850 Norton Commando. Been having an ongoing issue with "clutch slip" ever since I bought the bike and got her roadworthy. The clutch only "slips" in first gear, usually when I get to around 3000 rpm or so. No "slippage" noted in any other gear. To cut a long story short, I have learned way more about Norton Commando clutches than I ever thought I would need to know. Currently running a Norvil belt drive with 5 thin barnet fiber friction plates, 5 plain steel plates, a thin pressure plate and a pushrod (gearbox oil) seal. As stated above, in any gear other than first, no problem!
I recently noticed that when in first gear, if I hold the gear lever up with my right foot, the clutch does not "slip". It seems like the clutch is actually not the problem and the issue is that when in first gear and under load, the gearbox is trying to jump out of gear, although it is not making it to neutral. To put it another way, when in first gear, and I do NOT hold up the gear lever, and experience "slippage", when I release the throttle and the revs drop, first gear then re-engages, i.e it seems that the gearbox is not fully jumping out of first gear and into neutral - which of course, if it had, I would have pointed my finger at the gearbox as the source of the problem a long time ago!
Question: Anybody got any ideas about what could be wrong with the gearbox / what action I should take? The bike has approx 20,000 miles on it and the gearbox may not have been touched since new, although it is possible a previous owner may have made a mess of it. Regardless, I highly doubt it has ever been properly rebuilt. In regards to general operation, the gearbox works well, quite similar to my other two bikes, both of which are equipped with AMC type gearboxes.
Thanks!
1974 MkII 850 Norton Commando. Been having an ongoing issue with "clutch slip" ever since I bought the bike and got her roadworthy. The clutch only "slips" in first gear, usually when I get to around 3000 rpm or so. No "slippage" noted in any other gear. To cut a long story short, I have learned way more about Norton Commando clutches than I ever thought I would need to know. Currently running a Norvil belt drive with 5 thin barnet fiber friction plates, 5 plain steel plates, a thin pressure plate and a pushrod (gearbox oil) seal. As stated above, in any gear other than first, no problem!
I recently noticed that when in first gear, if I hold the gear lever up with my right foot, the clutch does not "slip". It seems like the clutch is actually not the problem and the issue is that when in first gear and under load, the gearbox is trying to jump out of gear, although it is not making it to neutral. To put it another way, when in first gear, and I do NOT hold up the gear lever, and experience "slippage", when I release the throttle and the revs drop, first gear then re-engages, i.e it seems that the gearbox is not fully jumping out of first gear and into neutral - which of course, if it had, I would have pointed my finger at the gearbox as the source of the problem a long time ago!
Question: Anybody got any ideas about what could be wrong with the gearbox / what action I should take? The bike has approx 20,000 miles on it and the gearbox may not have been touched since new, although it is possible a previous owner may have made a mess of it. Regardless, I highly doubt it has ever been properly rebuilt. In regards to general operation, the gearbox works well, quite similar to my other two bikes, both of which are equipped with AMC type gearboxes.
Thanks!
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