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I need to replace my plates on my 1963 A65 4 spring clutch. I’m not a racer or even a tourer, no heavy use. I just need plates that will do a standard job. I’m also a bit broke at the moment 🤷‍♂️

Soo, aluminium friction plates or three time the price for steel?

Many thanks for your help and advice

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As many knackered up engagement tangs as I have seen with steel, I'd be more than a bit leery with aluminum. I just spent $60USD on steel plates, the extra cost will pay for itself in not having to renew them prematurely in time and labour alone.....

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Ally plates if you have an Ally clutchbasket, a steel basket will eat them up fast. More of a thing for racers.


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i remember aluminum barnett plates.

supposedly less rotating mass made a difference.

hard to adjust, they said, becausr of the greater coefficient of expansion. would creep on the starting line


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aluminum from an engineering perspective it the wrong material for this application , unless they have been HARD anodized


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I've seen steel plates slightly dished and blued from heat in normal use, so I wouldn't like to think what would happen to alloy plates which are softer.

Might be worth trying to find a used set of steel plates, then spending some time with a file to remove any burrs, finally sand them allover to remove any glaze.

I dont know what the price difference is between steel and alloy plates, but the steel ones seem to be available for about £8 each.

Let me know if you need a hand, I'm just down the road from you.


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My experience with Barnett plates ( the Brit dealer at the time said they were the right one for my T100 ) almost 30 years ago was dragging and tangs that were soon destroyed. Since then, standard everyday cheerful Charlie steel plates have served me well.

Cheers, Wilf


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There’s a small section about aluminium clutches in “Hailwood to Vincent” book, not sure if it was plates or baskets or both. Either way they didn’t use them for long due to trouble from cold vs hot expansion. When cold it would slip on the kick starter (talking about a race bike). The steel unit went back in and was fine.


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My race bike uses a NEB speedway clutch.
Alloy inner drum and alloy outer basket. The (4) friction plates are solid fibre on an alloy core and the (3) plain plates are hard chromed alloy.
These stand up well to the abuse of drag racing.

BTW the friction plates will fit a pre Commando Norton clutch for dry clutch applications


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Originally Posted by Andy Higham
My race bike uses a NEB speedway clutch.
Alloy inner drum and alloy outer basket. The (4) friction plates are solid fibre on an alloy core and the (3) plain plates are hard chromed alloy.
These stand up well to the abuse of drag racing.

BTW the friction plates will fit a pre commando Norton clutch for dry clutch applications

So how many times do you throttle off, engine brake & change gears running down the strip ?


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I warrant that idling in traffic on a hot day causes more clutch damage than drag racing.

I think it's been established that alloy clutch parts may be appropriate in racing applications, but probably not suitable for street use.


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Alloy plates work fine in modern clutches where the tangs are virtually a continious spline so there is a massive contact surface to distribute the load
Not so good on a BSA where are relatively few tangs


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Case closed.

I was hoping that a number of people would just say “oh yeah I bought alley plates, worked ok”. But noooo, not one of you. So I bit the bullet and bought the steel plates. No beer for me this week 😞🤷‍♂️

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I’ve done about 20k miles on a set of Al friction plates. Can’t say that I’ve noticed much difference compared to steel. Also running with high gearing which would tend to be hard on them.

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I've used aluminum drive and driven plates for years in BSA unit single dual sport bikes, C15's and B44's. They've been subjected to fairly hard use. The drive tabs on the alloy friction plates get hammered down quicker than the steel friction plates.

On the other hand, the tabs on the aluminum driven plates hold up pretty well but the wear surface glazes smooth fairly quickly. But a quick bead blast session on the metal plates and a solvent wash for the fiber plates and the clutch holds well again. They are lots lighter and can make a noticeable performance difference on something like a C15 250 that frankly, needs all the help it can get.

So I guess the point is, lightness and performance will be improved but they will also need more maintenance.

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Alloy swell with heat and friction. Pull up to give way and you haven't got neutral, the friction expands them and with the lever at the bar it starts driving away.

I've tried all sorts. The narrow 7 plate set are trouble free, no sticking, no slipping and simply work like an efficient clutch. The clutch fibre is probably the same as std but there is more pressure being applied by the same force.

Some specialty clutch may be fine for their purpose, but for trouble free operation Narrow ones, though MAP plates have also been good. Ones that stick are a real pain.


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The narrow 7 plate sets are surflex linings, that's why they are good.
You can just stick normal plates in the lathe and turn the fibre radius out
a bit, it's an old sidecar racers trick. As you say the reduced area increases
pressure and the force applied is on a larger diameter.

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Although you made your mind up not to go with aluminum plates, they might work on a street bike, but I have no experience with them on the street.

My experience on a race bike is to the contrary. I was given a set of aluminum friction plates, back when I was using a stock clutch and primary in my T140 engined road race bike. Since I was a long time motocrosser, I definitely started hard, so let's start there with what I mean about starting hard--I was especially hard on clutches, start at 5000 rpm or so torque peak, feed in the clutch at full throttle at a rate that lets the engine stay at peak torque rpm and carry the front wheel about 4 inches off the ground and full engagement happens out there 50-75 feet. Anyway, in the middle of the second race weekend (Friday practice, Sat/Sun practice and races) it sheared all the aluminum friction plate tangs off and I lost drive. A little messy to clean up, but no problem, I had lots of other clutch plates with me. I called the guy that made them and he said, those were special race deals, meant to be used basically once and thrown away, so I didn't use them any more. Natch, Before and after using these, I did lots of maintenance on the stock primary/clutch. Eventually I quit using stock primary and clutch, went to Newby belt drive, which worked like a charm, with a little moderation during starts in deference to the dry clutch and the rubber belt.

Anyway, now I don't race anymore, I only ride on the street. The 7 plate clutches in my two Bonnevilles and my Spitfire are the bees knees, and I have never used aluminum plates on the street.


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