G15CS Clutch

Information relating to the Matchless G15 or AJS Model 33 750cc twin. This also includes the G15 Mk II and the G15/45
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Peter Morris
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G15CS Clutch

Post by Peter Morris »

Hi All,

I am having a spot of bother with the clutch on my 1967 (68 model) G15CS. I have stripped everything and had it inspected by someone with FAR more knowledge than I possess and all seems fine.

My problem is clutch slip, if I adjust as per the manual the clutch does not slip but the gears crunch and changing is difficult. If I adjust to engage gears easily it suffers from bad slip. I am currently adjusting it with the lever adjuster as I go….Something I have heard other members having to do with other models.

I read on the web of a chap that has converted to dry/belt drive because the AMC is not up to the power of the Norton engine, is that a thing?…..I doubt it somehow but…….

Any help/comments gratefully received.
Peter
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1608
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Re: G15CS Clutch

Post by 1608 »

It sounds like clutch drag to me. Either sticking plates, buckled plates or notchy clutch centre. The excessive clearance you achieve by tightening up adjustment will help overcome these problems but cause slipping.
OEW591
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Re: G15CS Clutch

Post by OEW591 »

My G15 will also slip slightly under hard acceleration but if you roll the power on gradually it's ok.
At one time the club had some rather stiff clutch springs but with these fitted you needed a left arm like Popeye to operate the lever.
I've also found that a Venhill cable for a Norton Atlas (try Mick Hemmings) makes for a lighter action and smoother take up so you might be able to tighten the springs a bit more with one of those.
I understand that perceived wisdom says that the engine is too powerful for the clutch hence the switch to the spring plate clutch on the Commando.
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Peter Morris
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Re: G15CS Clutch

Post by Peter Morris »

Thanks for the replies,

I have had the clutch apart and all seems ok. I put it back together with new springs (Wassells) and used ATF in the chaincase it is better than it was but still slips a bit.

It's most noticeable when overtaking or riding up hills. Would one of the Commando fit a G15?
G15 Roy
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Re: G15CS Clutch

Post by G15 Roy »

Hi Peter I have never had this problem with any of my G15s best to talk give me a call later after 7.
Roy
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Rob Harknett
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Re: G15CS Clutch

Post by Rob Harknett »

A slipping clutch heats up burns makes the plates shinny. Years ago, you needed to get max use out of everything. A good wash with petrol , then a dusting of Fullers earth on reassembly works wonders.
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Peter Morris
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Re: G15CS Clutch

Post by Peter Morris »

Thanks for your help Roy, very much appreciated.

Peter
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Peter Morris
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Re: G15CS Clutch

Post by Peter Morris »

Thanks Rob,

I done the petrol thing but not the Fullers Earth.

Peter
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Rob Harknett
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Re: G15CS Clutch

Post by Rob Harknett »

I did only use Fullers earth on the old cork inserts. Just before Jampot 2013 my old 36 AJS clutched slipped, could not even kick it over. I washed in petrol and lightly sanded the plates with 400 wet & dry taking off the glaze. I had not used the bike since 2007 rally. Took only 2/3 kicks to get it to start and run, in spite of petrol being 6 years old.
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bjork
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Re: G15CS Clutch

Post by bjork »

Peter Morris wrote:Thanks for your help Roy, very much appreciated.

Peter
Come on then Roy! What's the secret? My petrol is fresh so it can't be that? :headbang:
Using yesterdays technology to create tomorrows problems today
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