Clutch chain wheels

forgive me, I could be talking out me butt but here goes,

isn't your clutch the AMC with cush drive rubbers in the spider as fitted to all AMC machines? I have not heard of different depth chain wheels but there are different depth covers/ spring containers, in what way can you not get the adjustment correct?

register as a guest on the AJS/Matchless club site and have a read of the tirade of clutch questions and answers posted here,

kind regards

Hi Keith,there certainly are different depths of chainwheels.My '67 Atlas has five friction plates,and when i bought a new one from Les Emery,it will only accomodate four friction plates,and Les tells me the deeper ones are no longer available,but he assures me the four plate ones are adequate.Not sure which one you have-how many friction plates are in yours?

Ron Proctor.

Previously keith_parsons wrote:

Hi,

I wonder if anyone can tell me what the depths are of the pre 64 and post 64 clutch chain wheels. I don't seem to be able to get the clutch adjustment correct with the Atlas gearbox I'm using and wonder if I have a mix of parts from the early and late clutches.

Thanks

Keith

There were not many changes made to the SS clutches used on the Norton Twins from 1961 onwards. The depth of the basket was unchanged.

What tends to mess up these clutches is when the plates are changed. People mix old with new and then find it slips. The wrong pushrod or pressure plate (as Richard mentions) can also cause some grief as well as poorly made cables.

My own Atlas used to eat clutch cables. Generally the nipple pulled off at the lever end after about a year of riding.

The other issue with cables being that most replacements are manufactured with a Nylon outer sheath. This would ok but for the tortuous run the cable has to make on its way to the gearbox. Usually there are 2 right angle bends by the headstock and a tight loop near the gearbox. The Nylon allows the outer casing loops to open and close, whenever the lever is operated, before actually causing any movement of the pushrod. The end result being minimal lifting of the plates, a dragging clutch and crunchy gear changes.

I've a 58 Dommi and most of a 650ss. It's the alloy pressure plate that is different. The 650's is shallower than the Dommi's otherwise it would hit the outer primary chain case when the clutch is deployed.It allows for an extra plain plate (tangs on the outside) and a 'half' plate - friction pads one side only. I'm afraid I can't remember how many plates there are and I'm away from home at the mo' so can't go and look!

Regards,

Ian.

Attachment shows two of the three pressure plates available depending on model. The one on the left would suit most pre-1961 bikes such as 88, 77 and 99. Most with 10 clutch plates in total including the chainwheel and half-plate. The singles used a similar pressure plate but the basket had less plates in it.

The 88SS, 99SS, 650, Atlas and Hybrids used the much thinner pressure plate (shown on the right). These clutches had a total of 12 plates. The later clutches also used thicker but slightly shorter springs in the pressure plate.

Phil- on this topic - regarding clutch cable runs. Some run along the top tube and curve down to the rear wheel. Some run down the front tube and arrive along the bottom swing arm. But after all these years the route owners choose seems to be random. Do you know which was original and when they changes - and if it has any effect on how well they operate?

The orriginal route went round the top of the steering head, under the tank on the rhs ,crossed the engine and dived round the back of the oil tank where it is dragged accross a sharp corner of the oil tank and not given a very straight line into the box. The other route sounds worth a try but would need a longer cable than std?. Straight bars drag the cable up over the fork nuts and make things heavy, a set of 1" bar risers would make a big difference and still allow the use of the popular straights.

Thanks Rob. But I do apologise. I should open another thread... I'm going daft. I'm thinking about speedo cable!

Regarding the question.. my 1963 88SS has 5 double sided friction plates. The pressure plate looks like the one on the left of Phil's post although i don't think the turned down edge is quite as deep.

My notes tell me that in 2006 I replaced clutch. I bought 5 full two sided friction plates plus one single sided plus one plain for some reason.

I only took out 4 full plates. With 4 plus the half plate the stack measured 1.15 ins. The new stack with 5 plus half was 1.25 ins. The older plates were 4.5mm thick and the new ones 3.5mm "genuine Norton".

Dave & Robert......you have almost answered the question of cable routing by yourselves. I went to 'cable man' and asked for a Nylon lined cable for the 650 Manxman which was a few inches longer than standard. I then ran this across the the back of the headlamp shell and then under the right hand side of the tank next to the upper rail. This gave a nice easy curve after the headstock....which is the killer area for most cables. The extra length also allowed me to have a fairly open loop behind the oil tank into the gearbox. The combination of Nylon and easy curves changed the clutch lever loading noticeably for the better.

I like Robert Tuck's idea of improving the cable run with one inch bar raisers.

This would also give a better, more comfortable,angle for the levers.

Anybody Know if there are any available out there?

Regards,

Chas