1972 Lightning Clutch

[72 Lightning]

Hi All, during hard acceleration on my Lightning the clutch occasionally slips. I have taken it apart and having removed the clutch plates noticed that the clutch sprocket wobbles around quite a bit. Not sure if this is normal or I should be looking for something else. Any guidance would be greatly appreciated. Thanks.

[Ian C]

There is always some slight wobble when the plates are removed. Stating 'They all do that Sir' won't help you, but I had similar clutch slipping issues with my 1971 OIF A65 when at higher speeds. I upgraded the cush drive to 72 spec (bolted front to rear) as on both 71 style endplates the countersunk screws had a tendancy to work loose and this was successful for some time. What I didn't do though before my trip to the Danish rally in 2015 was to check the cush rubbers, so the cush bolts worked loose due to the extra vibration from the spider movement, but I managed to nurse the bike from Hamburg to the camp with a seriously slipping clutch (then spent a day and a half repairing it). Cutting a long story short, when back home, I removed the BSA clutch and chain and replaced it with a Bob Newby clutch and belt drive kit and have never had to look at the clutch seriously since.. HTH

[DAVE BRADY]

Hi,

As you have already partly stripped the clutch try just replacing the rollers and thrust washer. If after careful set up after reassembly there is still some slip on hard acceleration then try a bit more pressure on the springs - another turn may be sufficient.
I know it is a pain having to remove the primary case to do this but if your case has the internal casting left over from the earlier case then cap can be retro fitted to make it easier.
Even if the case is plain inside there is just enough thickness to fit a cap anyway.  It makes life a lot easier.


Dave.

[Gup holland]

My opinion is that the original clutch is to weak to cope the power of the engine, specially when hard accelerating.
Newby clutch is nice stuff, but expensive and not easy to obtain, have no experience with 7 plate clutch system.

[Daz]

 I was having clutch slip issues on my Lightning, tried new plates and increased spring pressure but it still slipped and dragged.
 I've now fitted a 7 plate clutch kit and can highly recommend it, no slip with the standard springs at a light setting and it disengages fully.

[Roy]

I have found some pattern plates are just not up to the job ,changed to surflex brand then ok

[72 Lightning]

Thanks for all of your replies. I will check the roller bearings and thrust washer first then go from there.