Clutch slip feel?

Information relating to the Matchless G9 or AJS Model 20 500cc twin
Chris B_LAPSED
Posts: 45
Joined: Mon Dec 28, 2020 8:31 am
Location: Nottinghamshire

Clutch slip feel?

Post by Chris B_LAPSED »

Hi all so just had a run out on the G9 and she was riding beautifuly for majority of the ride then for the last 10 miles it seems like the clutch was slipping but I'm pretty much sure its not that. Symptoms revving but taking its time to pull. Like I say it was running fine most of the way then all of a sudden it started to do that. Clucth lever has a nice amount of play.... any ideas what to look for other than the clutch.

Regards
Chris
Mick D
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Location: Aberdeenshire

Re: Clutch slip feel?

Post by Mick D »

Hi

Engine revs increasing with no associated rise in speed can only be clutch slip or a problem with the shock absorber. If it's the shock absorber you will hear it going over cam, (which a correctly set up one should not be able to do).

Start investigating why the clutch is slipping - check the spring pressure and ajustment of the release mechanism.

Regards Mick
g80csp11
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Re: Clutch slip feel?

Post by g80csp11 »

check the primary oil level is not too high due to wet sumping during lockdown, if its too high the clutch could slip
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1608
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Location: ESSEX UK

Re: Clutch slip feel?

Post by 1608 »

And, don't just rely on there being "plenty of play" at the clutch lever. Have a quick look under the inspection cap on the gear box and check there is play at the push-rod end.
Chris B_LAPSED
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Joined: Mon Dec 28, 2020 8:31 am
Location: Nottinghamshire

Re: Clutch slip feel?

Post by Chris B_LAPSED »

So got the inspection cover off what exactly am I looking for? Can obviously see the clutch cable but what is normal.

I topped the gearbox oil up a few weeks ago and been a few rides since and looking down the inspection i can't actually see any oil there now. There is signs of oil leak under neath but not sure where from

Regards wet sumping I keep the oil tap off when not in use and have had a few rides so it can't be that.
SPRIDDLER
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Re: Clutch slip feel?

Post by SPRIDDLER »

You haven't shown the year of your bike in your Profile so you could have a Burman or an AMC 'box, but whichever it is ......

As John (1608) mentioned the clutch is adjusted at the pressure plate. A cable adjuster only adjusts the free play of the cable, not the clutch.
To check for clutch slip you don't have to get kitted up and go out but just put the front wheel against something solid and try to ride away as you would normally. It's difficult to describe the correct amount of clutch 'grip' needed but you should be able to stall the engine in 1st at just above normal pulling away revs.
Chris B wrote:So got the inspection cover off what exactly am I looking for? Can obviously see the clutch cable but what is normal.
It seems you are looking at at the wrong end of the clutch, Crispy. You need to look at the other ( the pressure plate) end on the nearside (left side).
To adjust the clutch free off the cable adjustment completely or preferably disconnect the cable at the right hand end you were looking at. Then undo the locknut (it's plug spanner size) on the pressure plate (at the n/s) and screw in the slotted adjuster screw until resistance is felt. Then unscrew that adjuster screw half a turn and do up the locknut.
Don't you have the Owners Manual? You can find it here under 'Books'
http://archives.jampot.dk/
'There is a tide in the affairs of men
Which taken at the flood............'
Chris B_LAPSED
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Location: Nottinghamshire

Re: Clutch slip feel?

Post by Chris B_LAPSED »

I will have a look at the nearside plate tommorow i presume you meen in the primary case. Mine has only the small inspection cover as seen in the pics. Iv downloaded the manual so will have a read tonight. Will I need to take the primary case off to do the clutch adjustment. Pic attached

iv just tried the pulling off in 1st gear with the wheel towards the wall and it cut out all 3 times so that seems normal... Seems like its slipping when under hard revs. If riding as normal it seems fine.

Strange because I did 25 mile with no probs then all of a sudden it did it. My tick over was a little hight don't suppose that would have an effect would it?
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SPRIDDLER
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Re: Clutch slip feel?

Post by SPRIDDLER »

No you don't have to take off the primary outer chaincase as it's possible to access the adjuster through the small inspection plate. That's where the plug spanner (or an equivalent socket or box spanner) is handy to loosen the lock nut. Just loosen it. It's not necessary to remove it, besides if you try there's a likelihood it'll drop and then you will have the faff of removing the outer to get it back. Be careful when re-tightening the lock nut that the inner slotted adjuster screw doesn't turn as well. With a short box or plug spanner you can hold the adjuster screw with a screwdriver while you tighten the lock nut. It's a bit of a fiddle to get it right.
From your 'driving at the wall' test it would seem that it may be O.K. but it is more likely to slip when giving it a handful on the road or uphill in a higher gear, say 3rd or 4th.
The next check after adjusting the clutch and no improvement would be to increase the force of the pressure plate springs by screwing each of them in a turn and trying it on the road. (The more you tighten the pressure plate springs the more strength you'll need to apply to the handlebar lever when changing gear). You don't have to replace the primary outer to do the test but make sure that your Plus Fours don't catch in the primary chain.
The faster tickover won't be relevant.
It may be worn or contaminated clutch plates but checking them is another thing and a bit more involved. It's all in the manuals.
And a more basic question: Have you owned/been riding the bike for a while or is it new to you and has the problem just started?
'There is a tide in the affairs of men
Which taken at the flood............'
Chris B_LAPSED
Posts: 45
Joined: Mon Dec 28, 2020 8:31 am
Location: Nottinghamshire

Re: Clutch slip feel?

Post by Chris B_LAPSED »

Thanks for that info Spriddler I'll certainly go over those things and check. Yes I would defiantly say 3rd & 4th gear is worse. Iv owned the bike around a month and got through all the niggly bits and was finally happy until today which like I say 20 odd miles in the bike started slipping but up until this point it was absolutely running lovely i though finally iv got all things sorted. Except for the leak on the primary side (fitted new uprated band so I think its actually coming from else where) but that's the least of my worries.

I owned a G3ls a couple of years ago but never needed to do any work as the previous owner put all the blood and sweat into her so it was just a case of riding 😉

This G9 has been laid up from what I can gather but iv sorted all the niggly bits now iv just got to sort this clutch slip. Like I say it very strange as iv ridden the bike 5 times each around 30 mile and the clutch slip happened twice...

Hoping to get it all sorted for spring 🙏

As you can gather I'm a novice but certainly don't mind getting the spanners out

Thanks again
Chris
SPRIDDLER
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Re: Clutch slip feel?

Post by SPRIDDLER »

If folk didn't need any help/waffle/blather I'd be very bored Crispy, as for the past ten years I've not been able to do much fettling one-handed.
The G3LS is a lovely bike. I rode my '54 solo around Europe (Pyrenees etc) with a tent for 2,400 miles as a 2 month retirement adventure and all I did was change the oil twice and adjust the rear chain once.
It's a bonus to be able to get familiar with a new bike and sort these inevitable niggles during the lockdown in the comfort and with the tools in the shed rather than in the rain at the roadside. To coin a phrase I used as a charter skipper when I kept us in harbour due to bad weather: "It's better to be in here wishing you were out there than out there wishing you were in here".
;)
'There is a tide in the affairs of men
Which taken at the flood............'
Locked