Heavy Norton Commando clutch

Hi everyone, I'm new to this site. I've owned my 72 norton since 1981 and have never had a problem with the clutch lever until I recently hurt my left wrist. I have always known that the pull was heavier than most other motorcycles, but it never bothered me until now. I've read how adding another steel plate can lighten up the pressure, and I understand how it could lighten the pressure. What I don't understand is where do I add the plate within the clutch pack, and no matter where I put it, won't it be beside another steel plate? (Including the pressure plate)
Thanks for any help and advice.

You put it in first - against the clutch basket and before any fibre plates go in - works great. We have done this easy mod to all our nortons and it lightens the clutch with no slipping at all. It doesn't matter that it is going beside the steel plate that is rivited (?) to the clutch basket because it is not spinning and is only acting as a spacer.
Johno

Hi TPV
My clutch can be pulled in with one finger, but I don't know your setup....do you have fibre or bronze plates?
I have fibre 'Sureflex' plates.
But when you pull the clutch in you are only bending the leaves of the diaphram spring, whetever plates you have in the basket.
So what I advise is this:-
1) Purchase a Venhill 'Featherlight clutch cable, or similar. This is a Tethlon lined cable. Make sure the routing of the cable takes the path of least resistance, with the minimum of bends, and any bends being the max radius possible....this alone can transform your clutch. (Lube it well with light oil, like 3 in 1).
2) Make sure your basket is 'full' of plates.....i.e. when you put all the plates in including the last 'pressure' plate (the one the spring operates on) and the spring you should just nicely be able to fit the wills ring (the circlip thing)....there should not be a big gap between the spring and the groove....the spring will be about 'flat' when you put it in. When you study the operation of the spring it should start off slightly concave and go to slightly convex when you pull on the lever. Johno is correct in his advice of where to put the additional plate if required. Set the clutch rod just clear.
3) Open the small round inspection cover on the gearbox and study the cable routing....it comes through the gearbox through a tapped hole with an adjuster on the cable, and connects to the cam arm. If the cam arm is not lined up at the correct angular position it will make the cable inner rub against the cable adjuster.....this is a common problem with AMC boxes. You would have to whip the cover off and tweak this cam round to suit....easy job to get right....much easier to get wrong!!! This can make a massive difference to the operation of your clutch.

None ot the above will cost you much, but should transform your clutch.

Cable routing and the alignment of the clutch release mechanism to the cable hole in the gearbox cover are prerequisites. Check those things first.

When you pull the lever in you should feel a "snap" as the diaphram spring goes over its center point. If you don't get that, then it would probably benefit from a shim plate. The extra plate can be inserted at either end - mine is right behind the pressure plate.

The thickness of the shim is critical for reaching the perfect compromise between pull effort and clutch slip. I found that a stock .080 thick steel plate was too much - easy pull but slipped under load. Old Britts sells steel plates in thicknesses from .060 up in .005 steps. I ended up with .065 for the perfect clutch. They'll sell you the complete set and let you return what you don't use. It's a good deal.

I would be VERY careful putting a steel plate in first as some clutch baskets do not have splines deep enough . This will allow the steel plate to drop out of the spline and spin in the basket. I would put the extra steel in before the pressure plate . I have never seen commando outer gearbox cover with a threaded cable hole or an adjuster at the gearbox.

http://atlanticgreen.com/ndnsclutch.htm

This is a great primer of information on the Commando clutch. I can attest to the effectiveness of the Atlas actuator and all the various tweaks, but you need to start with making sure that there's nothing actually wrong with your clutch. Misaligned actuator, miss-routed dry cable, even the wrong lever sometimes. I too had a medical problem that made the clutch an issue. I went to great lengths to get it as light as possible, including a roller bearing in the lever. Medical problem resolved, but I still get to keep the really light clutch.

Thanks for the advice, everyone. The cable is routed as per the INOA Tech manual, and I lubricate it with dry graphite. The Actuator arm is aligned with the cable, but I'll double check it when I add the plate. Hopefully the .080 plate will work because I have a few extras.
Tom
72 Combat
73 850
72 BSA Lightning

A long time ago I sorted out my clutch and one of the things that helped a lot apart from the teflon coated cable was a small mod to the battery box to give the cable a straighter path out from the gearbox

Also I am ashamed to admit it, I wacked of with a cold chisel every other leaf from the diaphram spring, makes a big difference and no I don't have clutch slip!

bill said:

...I have never seen commando outer gearbox cover with a threaded cable hole or an adjuster at the gearbox.

Click to expand...

I haven't either. However, the Manx outer cover does have a threaded adjuster. The Manx gearbox also has a very different actuating arm inside. I'd guess that if someone has a threaded adjuster it is likely a Manx outer cover or a Quaife replacement cover.

SteveMinning said:

bill said:

...I have never seen commando outer gearbox cover with a threaded cable hole or an adjuster at the gearbox.

Click to expand...

I haven't either. However, the Manx outer cover does have a threaded adjuster. The Manx gearbox also has a very different actuating arm inside. I'd guess that if someone has a threaded adjuster it is likely a Manx outer cover or a Quaife replacement cover.

Click to expand...

or a dommie

When we started testing the Commando prototypes, I was riding a 3-year-old 650SS company hack to and from work. it had the old-style clutch, though the friction inserts weren't slices of wine-bottle corks like my old A7. The Commando was a revelation, lever force down by 90 percent, smooth and progressive.

If you have a high clutch force at the handlebar lever,it's not right. It shouldn't be more than a couple of popunds on the cable, divided by thye leverage. My first check would be the cable. At Norton, we used to get our Bowden cables from a guy who ran a "factory" on a chicken farm out in Dorset or Somerset. He'd dreamed up a cable with a Teflon-lined outer and a braided inner steel cable impregnated with molybdenum disulphide and graphite. Occasionally, I drove the company van down there to pick up a production batch. Imagine Honda doing something like that!

I've seen him demonstrate a clutch cable when he tied a knot in the assembly, pulled it as tight as he could in a vise, and the force to move the inner over full range was only about 2 pounds.

I can't remember the company name, but we used them for clutch and brake cables on both the Commando and the AJS Stormer. Maybe there's someone out there still making cables like that. I believe he had a patent, but it will surely have expired by now. Given the age of most still-living Commandos, maybe that "tribal" knowledge has been lost.