Clutch

Information relating to the Matchless G5 or AJS Model 8 350cc Lightweight
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Rob Harknett
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Location: ESSEX UK

Re: Clutch

Post by Rob Harknett »

Think you hit the nail on the head there Steve.
I had a bike under restoration for a long time, at one stage it would start ride etc but the wiring need finishing. During this period I would run the engine up occasionally, after first give the starter 2/3 kicks with the clutch in to free plate.
Its habit always 2/3 , then get the engine turned to the point for the kick to start it. Having done that a few times. I then got a guy to finish the bike restoration off for me. He had the bike a few months in the queue. During that time my new, or rather old but hardly ever used clutch, had stuck solid. The chain case full of sumped oil that stuck it together ???? Must had been as it never stuck when I was starting it every few weeks.
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robcurrie
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Re: Clutch

Post by robcurrie »

Paul, it works the same way as a rubber suction cup on glass - if you wet the cup it sticks better because it forms a better seal to maintain the vacuum.

Sidenote: Gauge blocks used in engineering shops for measuring are so accurately ground and lapped that the metal blocks will stick together.

Rob C
JEAN-NOEL
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Re: Clutch

Post by JEAN-NOEL »

Hi all,
In 1965 I had a 1957 G11. As I was living in a cold area clutch was prone to be stuck. Never in summer. Often it was just impossible to free the plates only applying kick start. I starded the engine, pushed the bike as fast as possible, jumped on it, and select 2° gear. Open the throttle a bit was sufficient to free the clutch. But...I was 17 !
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Ozmadman
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Re: Clutch

Post by Ozmadman »

Hi again, can someone just put me straight please? as I am getting some weird stuff happening with my clutch and I don't want to start it and try to put it in gear until I am sure it's ok

So, With the clutch pulled in, in gear, should you be able to start it with the kick start? as sometimes it turns over and other times it doesn't and you feel a resistance (clutch slip?) but no engine movement yet at other times the back wheel still wants to turn with the clutch lever pulled in? it's got fresh SAE 40 in there. The pressure plate is moving out ok when you pull the handle bar lever in, don't really want to pull off the primary cover again especially as I have just filled it with oil and got it nice and oil tight.
Thanks
Paul
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
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iansoady
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Location: Hall Green, Birmingham

Re: Clutch

Post by iansoady »

Ozmadman wrote:Hi again, can someone just put me straight please? as I am getting some weird stuff happening with my clutch and I don't want to start it and try to put it in gear until I am sure it's ok

So, With the clutch pulled in, in gear, should you be able to start it with the kick start? as sometimes it turns over and other times it doesn't and you feel a resistance (clutch slip?) but no engine movement yet at other times the back wheel still wants to turn with the clutch lever pulled in?
Thanks
Paul
No. The clutch takes the drive from the kickstart to the engine - if it's pulled in then the engine shouldn't turn (but will if the clutch is dragging). If the bike is in gear and you work the kickstart the back wheel will turn whether or not the clutch is withdrawn (unlike many Japanese bikes). Hence if you stall at the traffic lights you have to find neutral then start the engine then get back in gear which can irritate people behind you.......
Ian
1931 Sunbeam Model 10
1999 Honda SLR650
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Ozmadman
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Location: ESSEX UK

Re: Clutch

Post by Ozmadman »

iansoady wrote:No. The clutch takes the drive from the kickstart to the engine - if it's pulled in then the engine shouldn't turn (but will if the clutch is dragging). If the bike is in gear and you work the kickstart the back wheel will turn whether or not the clutch is withdrawn (unlike many Japanese bikes). Hence if you stall at the traffic lights you have to find neutral then start the engine then get back in gear which can irritate people behind you.......
Thanks Ian, it may be all about nothing then as I was concerned that the clutch wasn't working correctly because the rear wheel was still turning with the lever pulled in, presumably then from what you are saying and just to check the operation, if I pull the lever in, in neutral, this should disengage the engine from the box and it shouldn't turn over?
Thanks
Paul
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
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Malleon
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Location: WREXHAM UK

Re: Clutch

Post by Malleon »

Correct !
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iansoady
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Re: Clutch

Post by iansoady »

Ozmadman wrote:
iansoady wrote: and just to check the operation, if I pull the lever in, in neutral, this should disengage the engine from the box and it shouldn't turn over?
Thanks
Paul
Indeed. And even if it is in gear (but in that case the rear wheel will turn).
Ian
1931 Sunbeam Model 10
1999 Honda SLR650
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Ozmadman
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Re: Clutch

Post by Ozmadman »

Thanks all, pity just can't go and check now as the bike is outside and covered and any work etc is weather( rain that is, not bothered if it is just cold) dependant. No garage or shed unfortunately. Need to get it sorted as M.O.T soon
Paul
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
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Ozmadman
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Location: ESSEX UK

Re: Clutch

Post by Ozmadman »

Just an update, all back together, clutch is fine albeit a little fierce compared to the old one but just need to get used to it and gearbox runs and changes fine, no oil leaks!! and no 3rd gear whine (yet!) and fitting a 19 tooth gearbox sprocket instead of the standard 18 is the way to go... at least at 40mdh now you don't think you are still in 3rd !!! happy bunny. just need to wash all the ACF50 off now and give it a polish then off for the MOT..

Paul
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
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