Author Topic: C11G clutch  (Read 535 times)

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Offline Steve P

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C11G clutch
« on: October 09, 2019, 11:00:25 am »
Hi
I'm new to the site so please accept my apologies if this subject has been covered. Could someone please point me in the right direction if so.

I purchased a 1955 semi assembled C11G a few weeks ago.

There's no clutch inside the chaincase! All that's in there is a splined shaft with a pushrod and two nuts, one of them a left hand thread.
I've been searching the internet for parts and things like the chainring/basket seem to be unobtainable.

Should I sink into the depths to despair? Or is there anything any member could suggest as a solution.

I believe the clutch is the three spring type. Does anyone know where I could purchase a complete clutch or at least the major components?
Has anyone managed to fit a different type of clutch onto the  gearbox shaft? If so any information would be gratefully received.

Cheers.

Steve

Offline Owen

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Re: C11G clutch
« Reply #1 on: October 09, 2019, 12:13:09 pm »
Hi Steve P,
Welcome to the site please add your bike details to the register. You need a 3 spring clutch assembly for your bike. The bits come up on E Bay occasionally and members might have bits to help you out. Do you have a user and parts book for your bike? If not send me a personal message with your email address and I will send you some by email.
1940 C12 (350cc)
1945 C10 & C11
1953 C10 & C11
Anyone want a B20 in need of a lot of tlc

Offline johnboyfully

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Re: C11G clutch
« Reply #2 on: October 09, 2019, 12:22:52 pm »
Welcome to the site Steve. Never despair! I’ve had my C12 for 3 years and (some day foolishly) I started a full strip down last January! She is almost back together. I’ve acquired a fair few spare parts and definitely have some clutch parts. Can you let me know exactly what you need by either description or part number and I will do what I can to help you out. I’m no mechanic or engineer believe me and it can be very frustrating at times but I’ve learnt that it is all part of the never ending learning process. But I love my little bike and I’m really looking forward to see, hear and smell her breathe again! There is a wealth of knowledge and experience on here and they are all very patient with novices like me!! True they sometimes argue like married couples over seemingly minor issues but that’s just part of the banter. Good luck with your project. Cheers, JBF

Offline Steve P

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Re: C11G clutch
« Reply #3 on: October 09, 2019, 02:30:41 pm »
Hi thanks for replies.

Owen, I do have the parts lists and service book - both from Draganfly. I'm struggling to find where to register my bike details. Should I include non BSA models.

JBF, thanks for the sympathy. I'm looking forward to actually riding the bike, I think this may be some time coming. My knees and back no longer cope with kickstarting 750 and 850 twins. I think there's going to be a bit of a learning curve.

I'm looking for all the major clutch parts. I'll probably buy new bearings, rubbers, plates and bolts. I'm hoping these more consumable parts should be fairly readily available.
I think what I'm looking for is;
Chain wheel - 29-3461
Centre end plate - 29-3466
Centre vane - 29-3465
Centre - 29-3464
Spring plate - 29-3467
Thrust washer - 29-3473

Any help is really appreciated

Steve

Offline johnboyfully

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Re: C11G clutch
« Reply #4 on: October 09, 2019, 03:42:55 pm »
I’ll have a look and get back to you in a day or so Steve. I’ve definitely got a thrust washer as I bought one recently (inadvertently)! Cheers, JBF

Offline Steve P

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Re: C11G clutch
« Reply #5 on: October 09, 2019, 04:49:56 pm »
Thanks JBF
I really appreciate your help
Steve

Offline Owen

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Re: C11G clutch
« Reply #6 on: October 09, 2019, 05:03:56 pm »
Try the following link
http://bsac10c11c12.co.uk/smf/index.php?action=form;n=5

Only bsa C models please.
1940 C12 (350cc)
1945 C10 & C11
1953 C10 & C11
Anyone want a B20 in need of a lot of tlc

Offline Steve P

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Re: C11G clutch
« Reply #7 on: October 09, 2019, 05:24:36 pm »
Thanks Owen I've registered.

Offline chaterlea25

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Re: C11G clutch
« Reply #8 on: October 09, 2019, 07:32:57 pm »
Hi Steve,
According to this topic the clutch is the same as AJS14 / Matchless G2 which would widen the search

https://bsac10c11c12.co.uk/smf/technical/some-useful-parts-info/msg51696/#msg51696

John

Offline Steve P

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Re: C11G clutch
« Reply #9 on: October 09, 2019, 07:51:38 pm »
Thanks John
Great info and help

Online BSAc11g

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Re: C11G clutch
« Reply #10 on: October 10, 2019, 04:08:57 am »
AFAIK ( or think I know ) the early gearboxes where made by BSA thus have a taper & key for the clutch hub to mount on and as such almost any BSA clutch can be made to fit.
The latter light box , like the A series plunger box was bought in and is a Burman box thus the splined main shaft and the fact that non BSA clutches drop strait in.
Also the earlier tapered end main shaft can be retro fitted in finding a clutch hub is a big problem.
It all depends upon how confident you are and how much buggering around you fell like doing.

You will need an early & late parts book to see which parts interchange.
I have helped a member to fit the A series splined main shaft into an M 21  box so he could fit the 4 spring clutch and duplex chains.
Apart from the massive increase in primary ratio requiring the fitting of a side car drive sprocket it worked really well.
Bike Beesa
Trevor

Offline Steve P

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Re: C11G clutch
« Reply #11 on: October 10, 2019, 09:33:17 am »
Hi Trevor
Thanks for the info., and help.
I'm trying to leave the gearbox in one piece if possible. This is obviously a solution if all else fails. Thanks.

This is really helpful information.

In the past I've built a Norton with an AMC box and an AJS with a Burman box.
I just didn't have a forum like this to help.

Thanks everyone

Steve

Online BSAc11g

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Re: C11G clutch
« Reply #12 on: October 10, 2019, 02:43:25 pm »
It is nothing odd to open a BSA box and find 4 pairs of gears from 4 different boxes in there.
One of the reasons why Gold Stars had such success is you can build up near 30 different ratio boxes.
Thus it was affordable for weekend clubman racers to have a different box for every track.
From memory BSA made 8 different boxes for them.
One of the C series clusters is the same as an A series cluster but only 2/3 the price so it was very common to buy C boxes, strip the cluster out then scrap the cases which is most likely why come boxes are really hard to come by now days.
Bike Beesa
Trevor

Offline Steve P

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Re: C11G clutch
« Reply #13 on: October 10, 2019, 05:03:54 pm »
There must be stocks of these cases somewhere. I suppose they'll be with all those Norton engines and triumph frames left over from the Tritons. Unless someone is building Norumphs with BSA C11 clutches

Offline Owen

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Re: C11G clutch
« Reply #14 on: October 10, 2019, 05:53:56 pm »
Just to clarify. Up to 53 models had the 6 spring clutch assembly and taper shaft fitting. G, L, C12 ohv had 3 spring clutch assembly and splined shaft fitting.
« Last Edit: October 10, 2019, 09:31:48 pm by Owen »
1940 C12 (350cc)
1945 C10 & C11
1953 C10 & C11
Anyone want a B20 in need of a lot of tlc