Norton clutch on a10

[44T]

Hi all.
Please forgive me if this has been covered before...I have looked   
I have been offered a mainshaft from a plunger model, that l'm told will accept a Norton clutch.
Is it a worthwhile mod ?
Just wanting it to be smooth and strong
I'd appreciate any advice on any positives or negatives with going down that route.
My 59/60 GF was always going to have a g/box strip and check, and the standard 6 bolt clutch assembly looks tired out. Although there are loads of other jobs to do yet, I may sort the g/box and clutch now.
Thanks in advance.
Cheers

[limeyrob]

I'm not sure its worth the effort. If the 6 bolt is not up to it why not convert to a 4 bolt and leave the box alone?  You can check the internals through the square plate.

[groily]

I'm not sure its worth the effort. If the 6 bolt is not up to it why not convert to a 4 bolt and leave the box alone?  You can check the internals through the square plate.

A lot of work for no real gain compared with the easier upgrade, in my opinion also. Having had/got 3 x AMC 'boxes with 3 spring clutches, and having had 2 x 4 spring Beesa ones (on an A and  B) for many many miles, I'd say the latter were just as good. Certainly for all normal purposes, anyway. 
The only 'better' AMC one is maybe the diaphragm version which (in my experience anyway) develops no cable slack even in heavy traffic. (Quite heavy though, some reckon.)

[44T]

Thanks. I'm not totally sold on the idea. It's just that I think the g/box should be stripped and checked anyway (so much bodgery found elsewhere )!! Plus, it's on the bench  .
The plunger m/shaft that I know of, is part of a load of g/box parts that won't be about long, so want to know if I need anything for mine.
I'm told it's a simple conversion job? and was hoping someone would let me know, if that's not the case.
I'm fine with stripping g/boxes, it's more a case of .. is it as simple as slipping the Norton clutch on the plunger shaft, and the primary chain lines up with the primary drive sprocket and clears everything ?, or will there be all sorts of knock on problems to sort ? Cheers

[CheeserBeezer]

I tend to agree with Groily on this one. It is possible to make a six-spring work but they are crudely made compared to the 4-spring. All the components for the 4-spring are available new and I would recommend finishing it off with a billet pressure plate. Given that I'm old, and don't want to die in credit, I use the Bob Newby belt drives which, once set up correctly, are maintenance free........but you do need a wallet of considerable size!

[44T]

I tend to agree with Groily on this one. It is possible to make a six-spring work but they are crudely made compared to the 4-spring. All the components for the 4-spring are available new and I would recommend finishing it off with a billet pressure plate. Given that I'm old, and don't want to die in credit, I use the Bob Newby belt drives which, once set up correctly, are maintenance free........but you do need a wallet of considerable size!

 Thanks for that. What does it take to make a six spring work well ? How much would a 4 spring cost including a billet p/plate ? Could I do the Norton conversion cheaper , easier, cheaper and end up with a good strong smooth clutch, cheaper ?? Questions, questions   

[berger]

44T to make a six spring work without any slip and finding neutral with the engine running you need to be able to crack brazil nuts between your finger and thumb, i might have a 4 spring in the garage  [ i will look see tomorrow ] but you need an adaptor of the correct taper to keep the chain in line.

[chaterlea25]

Hi All,
If Norton clutch is fitted something like a Pearson Gold star sliding plate is also needed to seal the primary.
I have all the parts to do such a conversion mainly because I picked up a very good clutch for €80.
One caution is that there is very little support between clutch and mainshaft splines so do not go mad tightening the centre nut!!
I don't think you can fit in the plunger split collar and thrust washer?? But I have not mocked up the assembly to see if it is possible ??

John

[olev]

I think Muskrat has one in his cafe?
cheers

[scotty]

Here’s a link to an old post on 6 spring clutch renovation


https://www.a7a10.net/forum/index.php?topic=12425.0


I modified mine and it worked just fine

[bikerjohndavies]

I see that John Harding has a 4 spring clutch with adapter for sale on Ebay at the moment.

https://www.ebay.co.uk/itm/395934685301

[44T]

Thanks for all the responses. I've just had a better look at my m/shaft, and the taper and keyway is not great.  Probably salvageable,  but definitely worth looking at alternatives.
If I go the plunger shaft and Norton clutch route, is the m/shaft a straightforward job to fit in my s/arm model box, and are there issues with primary chain alignment ?
Cheers.

[chaterlea25]

Hi 44T,
The shaft is a direct swop, you will probably have to change over the 1st gears that are pressed onto the shaft.
As to the primary chain alignment you will have to sort that out ,
I will be interested to see how it goes

John

[muskrat]

G'day 44T.
As Olev said I have a Notrun diaphragm clutch on my Cafe. It was part of a belt conversion done by a fella down in Melbourne. Quite a nice kit, the clutch hub was made to match the BSA taper.
Cheers