Thanks for all the advice, I am familiar with the Norton diaphragm clutch as I had a Commando, never had any bother with it. I will have the cover off at the weekend and give the plates a clean, roughen the up if they appear glazed and try to increase the spring pressure. Will also take a couple of pictures so you can confirm if it is a Norton clutch
C: Clutch Norton clutch conversion adjustment to stop slipping under load
- Thread starter gibbin82
- Start date
I did use mine on the road, as well as racing , For many years, With the Norton type Clutch,
I used a valve lifter cable end, Instead of the long abutment, And by playing with different levers and where it was on the handle Bars, I could get a bit more lift.
I had to wire up the cable nipple to the clutch arm, Just in case it popped out..
And make sure the new abutment could not fall into the chain if the cable broke.
The things we did, When we were Young !. Cheers Bill.
I used a valve lifter cable end, Instead of the long abutment, And by playing with different levers and where it was on the handle Bars, I could get a bit more lift.
I had to wire up the cable nipple to the clutch arm, Just in case it popped out..
And make sure the new abutment could not fall into the chain if the cable broke.
The things we did, When we were Young !. Cheers Bill.
Had the cover off today, increased the spring pressure by a turn and a half also adjusted it to lift the plate evenly, hopefully it will ok now, will have a run out tomorrow to check
. Posted a couple of pictures below, please could someone confirm if it is a Norton clutch
Looks like my old one, Sort of 1960 s, Norton, Always thought 4 or 5 springs would be better,
The 3 were always going out of balance.
The thing is to keep it cool, Something I did on my bike later, Was a longer indicator lever, Made from Alloy
Plate, So as I pull up, I lean down and put in neutral by hand,
I am tallish and find it easy. I think it should be run Dry ?.
Maybe modern plates would make it better, I think they call them Surflex ?.
Also if you can get another Friction plate in, Might make it grip better ?.
Good Luck, Bill.
The 3 were always going out of balance.
The thing is to keep it cool, Something I did on my bike later, Was a longer indicator lever, Made from Alloy
Plate, So as I pull up, I lean down and put in neutral by hand,
I am tallish and find it easy. I think it should be run Dry ?.
Maybe modern plates would make it better, I think they call them Surflex ?.
Also if you can get another Friction plate in, Might make it grip better ?.
Good Luck, Bill.
Another one of Bill's Bodges !.
It's all I had Bruce, Hacksaw/Hammer and a Drill.
The hard bit was doing the centre of the Sintered Bronze plate, For 5 or 6 plates !.
The photo shows it didn't work too well !, But it got me to a 12.5 second Standing 1/4 mile, With 110 mph over the line, On my Road Bike.
Try it, It's not easy. Cheers Bill.
It's all I had Bruce, Hacksaw/Hammer and a Drill.
The hard bit was doing the centre of the Sintered Bronze plate, For 5 or 6 plates !.
The photo shows it didn't work too well !, But it got me to a 12.5 second Standing 1/4 mile, With 110 mph over the line, On my Road Bike.
Try it, It's not easy. Cheers Bill.
Yes, it's an AMC clutch, most probable Norton. But the AMC clutch was used on some AJS and Matchless models. Though your basket is a bit modified by adding square steel pieces to the slots and a ring around the basket.
Norton did a number of modifications so I can't tell exactly what you have. In -64 they made a deeper basket to put in more plates. In -60 they started fitting stronger springs. Don't know when they started to hammer marks in the steel plates to get them less prone to distortion. Before that (maybe around -56) they fitted the centre adjuster and skipped the mushroom lifter. And replaced the spring holding screws with nuts. Plus that they changed from friction plates with outer tags to inner tags. Plus some other mods before that. The Manx had a lighter clutch with fewer plates.
Really a bit confusing.
Norton did a number of modifications so I can't tell exactly what you have. In -64 they made a deeper basket to put in more plates. In -60 they started fitting stronger springs. Don't know when they started to hammer marks in the steel plates to get them less prone to distortion. Before that (maybe around -56) they fitted the centre adjuster and skipped the mushroom lifter. And replaced the spring holding screws with nuts. Plus that they changed from friction plates with outer tags to inner tags. Plus some other mods before that. The Manx had a lighter clutch with fewer plates.
Really a bit confusing.
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The Norton clutch is designed to run dry. Most usual cause for slipping is oil. Clean plates in petrol. Too much in the chain case is a probable reason. Some times oil is entering from engine or gearbox into the chaincase, overfilling chaincase. The Norton designer made it with SAE20 in mind. Of course the screw in the pressure plate must be adjusted for some free play. Also check that the pushrod isn't too short so that the pressure plate adjuster rides on the end of the mainshaft (own experience setting up a Manx). It can be wrong springs.
One problem with non standard clutch setups is that how much travel of clutch lever gives in pushrod travel. Which of course is as clutch lever force gives as pushrod force. A mismatch between lever length between swivel point and cable end and gearing in the clutch mechanism in the gearbox, can give either a heavy clutch or too short travel. Can fool you to set too little spring pressure.
Off topic on Nortons: The laydown gearbox has less travel disengaging the clutch than the AMC gearbox. The Commando clutch has even more travel.
One problem with non standard clutch setups is that how much travel of clutch lever gives in pushrod travel. Which of course is as clutch lever force gives as pushrod force. A mismatch between lever length between swivel point and cable end and gearing in the clutch mechanism in the gearbox, can give either a heavy clutch or too short travel. Can fool you to set too little spring pressure.
Off topic on Nortons: The laydown gearbox has less travel disengaging the clutch than the AMC gearbox. The Commando clutch has even more travel.
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