BSA Owners' Club Workshop Discussions

The BSA Workshop => Singles => Topic started by: Fraz on 21 Aug, 2024, 18:46

Title: B31 Clutch - should it run in oil?
Post by: Fraz on 21 Aug, 2024, 18:46
Just about to put my clutch back together after inspecting for wear and undecided if I should clean up the plates with brake cleaner?

The metal plates and friction plates were / are contaminated with oil.

Should they be coated with oil or should the clutch run dry? (Meaning I've got a leak issue somewhere)

Thanks
Title: Re: B31 Clutch - should it run in oil?
Post by: idie on 21 Aug, 2024, 22:01
They run wet.
Title: Re: B31 Clutch - should it run in oil?
Post by: Kernowpete2 on 22 Aug, 2024, 07:03
There should have been oil in the primary chain case when you took it off. Was there?
Title: Re: B31 Clutch - should it run in oil?
Post by: Fraz on 22 Aug, 2024, 11:03
Quote from: Kernowpete2 on 22 Aug, 2024, 07:03
There should have been oil in the primary chain case when you took it off. Was there?

Thanks
Title: Re: B31 Clutch - should it run in oil?
Post by: Fraz on 22 Aug, 2024, 11:04
Quote from: Fraz on 22 Aug, 2024, 11:03
Quote from: Kernowpete2 on 22 Aug, 2024, 07:03
There should have been oil in the primary chain case when you took it off. Was there?
Yes, plenty oil came out

Thanks
Title: Re: B31 Clutch - should it run in oil?
Post by: Pete C on 22 Aug, 2024, 13:38
it is essentially a dry clutch. The oil in the primary is only to lubricate the chain, clutch bearings and shock absorber.

If the clutch plates are soaked in oil you need to clean them and reassemble dry. Petrol is not the best way to wash the plates but everyone does it that way.

The level of oil in the primary should only be enough for the chain to dip into when running.
Title: Re: B31 Clutch - should it run in oil?
Post by: V500 on 22 Aug, 2024, 17:41
This is true, but the nature of the environment (plunger bikes aside) means that the plates will soon become oily again, though they work just fine like this.
Title: Re: B31 Clutch - should it run in oil?
Post by: Pete C on 23 Aug, 2024, 06:45
True, the clutch will not escape the oil being flung around by the chain. However the majority will be flung off again and the plain plates have channels in them to facilitate the oil's escape. A little oil is OK.