BSA Owners' Club Workshop Discussions

The BSA Workshop => Twins => Topic started by: DAVE BRADY on 23 May, 2020, 21:40

Title: warped plain clutch plates
Post by: DAVE BRADY on 23 May, 2020, 21:40
Hi All,

This is probably pertinent to all BSAs that have warped plain plates.  How can they be flattened again?  Mine are bit wobbly.
On getting some new replacements I find mine are not so bad as the new ones are wobblier. 
How many tons or tonnes would it take to get them flat?

Dave.
Title: Re: warped plain clutch plates
Post by: Bess on 24 May, 2020, 07:51
Hi,
     You can't readily straighten warped plates and end up with a usable item. Send the new wobbly plates back and ask for a set of flat.

Best wishes...
Title: Re: warped plain clutch plates
Post by: DAVE BRADY on 24 May, 2020, 08:25
Hi,

This what I thought that I would end up doing.  Shame really as, apart from the odd bit of a burr and the wobble, they are quite good. I checked them on a the base plate of my pillar drill and with a straight edge.
Images show the difference standing on edge with a gentle grip.  Shuffled them but still got the same hand.

Dave.
Title: Re: warped plain clutch plates
Post by: Allan G on 24 May, 2020, 09:47
Buy some surflex plates.
Title: Re: warped plain clutch plates
Post by: DAVE BRADY on 24 May, 2020, 09:52
Hi Allan,

That could be a solution but this is for the early A65 4 spring clutch.  The tangs on the plain plates are a unique shape and not easy to find.

Dave.
Title: Re: warped plain clutch plates
Post by: paulm on 24 May, 2020, 23:17
Dave this is a hard one some of the new ones are just as bad if not worst, as soon as you take delivery of new check them straight away
Title: Re: warped plain clutch plates
Post by: DAVE BRADY on 25 May, 2020, 07:43
Hi Paul,

Yes, I agree. If you look at the photos above you can see that the old ones I nearly scrapped are perfect compared with the new ones.  I have managed to find some NOS on ebay still in the preserving grease.  When they arrive it will be interesting to see how good they are.

Dave.
Title: Re: warped plain clutch plates
Post by: DAVE BRADY on 01 Jun, 2020, 12:36
Hi,

The NOS plain plates are just about perfect and I think the old ones I am replacing would do if necessary.  The new warped ones went back.  So all new plates, new rollers and a new basket I am looking forward to a really good clutch.  I may even splash out on new springs and SRM pressure plate.

Dave.