The BSA A7-A10 Forum

Technical => Clutch, Primary, Gearbox => Topic started by: derek taylor on 25.02. 2015 19:31

Title: clutch wash
Post by: derek taylor on 25.02. 2015 19:31
just a quick one lads what does people use to wash oil off there clutcu plates?
Title: Re: clutch wash
Post by: morris on 25.02. 2015 20:47
An of the shelf brake cleaner will do fine
Title: Re: clutch wash
Post by: Butch (cb) on 27.02. 2015 12:52
A pertinent question to the current situation on my Sportster. Having the luxury of a mixed and sizeable stable, some of my bikes don't get to go out so much. On the Sportster, last year I was having increasing difficulty clearing the clutch each time it had been standing a while. With no kicker I was attempting this by engaging a gear and then pushing back and forwards with the clutch held in before then firing up. But it got to the point where even that wouldn't do it.

I've recently pulled it down - primarily to check the alternator magnets in the back of the clutch drum. A well known weak point in the very early Evos. I'm digressing here, but mine had gone walkabout as it happens. Dammit - v. expensive, and I suppose could have led to a sudden seizure that could have killed me. Coulda, woulda, shoulda - but didn't so get over it.

Anyway, on pulling the plates they were really sticky and difficult to split. All cleaned up again now, but the suggestion is that I've used the wrong oil in there and this problem may repeat itself where that leaches out of the friction material. They are the originals (bike at a genuine 21k miles) but in good condition, but I may yet have to swap them out for new. I guess we'll see once we get into riding season and I take the bike off SORN.
Title: Re: clutch wash
Post by: derek taylor on 27.02. 2015 17:19
my trouble was clutch slip the oil i put in was what was recomended in the manual, i used to use atf now i'v stripped it down to clean it off i'm gunna put atf back in. *smiley4*
Title: Re: clutch wash
Post by: Butch (cb) on 27.02. 2015 17:23
I use ATF in the A10 ... running a 6 spring. Kinda just works.

(The Sportster shares it's oil between primary and the g/box, big twins are still pre-unit I suppose).
Title: Re: clutch wash
Post by: Johnny J on 27.02. 2015 17:31
Would you generally say that there is less slip with AFT than engine oil on a 6-spring?

Mine is not slipping but I have problems gettting it in neutral when engine running, would there also be a difference in this this using ATF?
Now I'm using Castrol single grade 50W.
I know the general opinion of 6-spring, don't want to change it right now, trying to get it to work as good as possible...
Title: Re: clutch wash
Post by: KiwiGF on 27.02. 2015 19:07
I tried atf with my 6 spring and it worked ok but as it made getting rid of leaks harder I switched back to sae30 petrol mower oil, briggs and stratton oil brand sae30 is red so l can see any leaks  *bright idea* *bash*....

The sae30 works ok and l did not notice any change in clutch slippage with either, my 6 spring clutch works perfectly and certainly as well as a triumph one, but it needs a bit more force on the lever than bikes with the triumph clutch, if I back off the springs to reduce the force it slips.

I did not wash the clutch when l made the change though.

The absolute "must do" on my clutch (and I guess all other 6 springs?) is to set the springs up using a dial guage to ensure they are adjusted so the pressure plate moves an equal distance all round, if this is not done it drags and neutral is harder to find at standstill etc.
Title: Re: clutch wash
Post by: Triton Thrasher on 27.02. 2015 20:49
I wash the plates in petrol.
Title: Re: clutch wash
Post by: muskrat on 28.02. 2015 09:41
As TT with petrol then wax & grease remover. But if they've been living in friction modified car oil for long no amount of washing will revive them.
Title: Re: clutch wash
Post by: derek taylor on 28.02. 2015 19:16
anyone tried using 3 in 1 oil
Title: Re: clutch wash
Post by: RichardL on 28.02. 2015 20:24
Except for gooey grease, I don't wee why there is any need to wash the clutch plates free of oil. The design was (is?) intended to run in engine oil (though many, and I, run ATF). Anyone care to explain why friction material that is de-oiled before assembly would make any difference other than, perhaps, running a little too hot for the first 15 seconds before the clutch is drenched?

Richard L.
Title: Re: clutch wash
Post by: morris on 28.02. 2015 21:07
Well Richard, when our clutches where designed oil was just oil and nothing more. There's people on the forum who may have a better knowledge than me, and with the danger that this will turn into another dreaded oil thread, I think that today's engine oil, as Musky points out, always contains friction modifiers to make it more slippery, and some other additives to make the oil film break up less easily (re; make it more sticky).
On the SA, I started with engine oil in the primary but begun suffering a sticky clutch (not to bad, but up to a point where the clutch  disengaged only after a second or two). I made the mistake of changing it to heavier grade gearbox oil, which only worsened it. I am now testing a 32 grade hydraulic oil in the primary. See how that works out...
Title: Re: clutch wash
Post by: bsa-bill on 28.02. 2015 22:11
I've a notion the problem with oily plates is they stick together and produce drag not that they slip so a lighter oil (ATF) is a better choice
Title: Re: clutch wash
Post by: RichardL on 28.02. 2015 22:59
All good, but these points don't really seem to require pre-washing the clutch to get it working with ATF, or some other light oil. I think these lighter lubricants would quickly dominate any residual heavier oil, sort of acting like its own wash. Just playing with the ideas. Nothing to get excited about.

Richard L.
Title: Re: clutch wash
Post by: muskrat on 01.03. 2015 06:24
I think clutch's work best dry. The oil is in there to lube the chain and rollers. The early 6 springers have that cover to keep out as much oil as possible (in the day).
Title: Re: clutch wash
Post by: derek taylor on 01.03. 2015 08:56
just had a look on sump magazine site spec for 1952 golden flash says dry multi plate clutch.
Title: Re: clutch wash
Post by: duTch on 01.03. 2015 12:05
 Yo Derek, that's because they originally ran inside the domed cover- "in the day", as Musky said...

 Mine leaks the ATF fairly quickly, seems to penetrate the drain screw a bit like that rusty nuts loosener with acetone thread that I need to comment on..

 I used chain lube on my primary one time when I had it apart, but when I put the ATF in I guess it washed it off
Title: Re: clutch wash
Post by: derek taylor on 01.03. 2015 14:54
anyone ever used link life on their primery chain
Title: Re: clutch wash
Post by: muskrat on 01.03. 2015 19:34
G'day Derek.
I did a quick search on linklife. It sounds the same as the old boiling in grease method. This would be OK if you did it every 500 miles or so. Primary chains travel a lot faster than rear chains, and who wants to strip the primary that often. It wouldn't help the clutch rollers or the slipper adjuster in plungers, and I'd be worried if any got onto the friction plates.