Author Topic: 1955 A10 Golden Flash 650cc - swinging arm model - clutch problem  (Read 6342 times)

Offline BrianS

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Thanks for the info Trevor - it is good to hear that the basket will fit at least a couple of models. Seller just needs to correct his advert. Waiting to hear from him.

Meanwhile, SRM have some new business  ;)

Brian
1955 BSA A10 Golden Flash
Exeter, Devon, UK

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'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
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Muskys Plunger A7

Offline BrianS

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Too late - SRM have already got my money! I appreciate the link but, having had a bad experience with both new and used clutch parts, I am hoping the whole new unit will allow me to forget clutch problems for the life of the bike. I am taking the advice of another forum member to spend on basics rather than farkles   ;)
1955 BSA A10 Golden Flash
Exeter, Devon, UK

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No worries Brian. It beats me why they didn't continue with the earlier plunger/rigid 6 spring. The only new part in mine is the friction plates (35 years ago).
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
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Muskys Plunger A7

Offline chaterlea25

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Hi Brian,
Have you opted for the complete SRM 4 spring clutch ?
If so you might read the post I put up some time ago on primary chain /sprocket alignment
http://www.a7a10.net/forum/index.php?topic=9646.msg70166;topicseen#msg70166

John
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1963 RGS (ongoing)

Offline BrianS

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1955 BSA A10 Golden Flash
Exeter, Devon, UK

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Yum yum, good choice Brian. Add a new chain and crank seal and the primary cover won't be removed again for many a year. $$$ that's more than a weeks wages for me  *eek*.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7

Offline BSA_54A10

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No worries Brian. It beats me why they didn't continue with the earlier plunger/rigid 6 spring. The only new part in mine is the friction plates (35 years ago).
Cheers

Because they did not own it.
It is a Burman clutch either bought in or made under license from Burman.
I had always believed it was bought in as plungers were only meant to be a stop gap model while BSA developed a swing arm that they did not have to pay royalties on.
If plunger were to remain then to only be available with chair attached.
But like a lot of things they just got a life of their own.
Bike Beesa
Trevor

Offline BrianS

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It seems that Flash will have another restful weekend  *sad2*

I contacted Stewart at SRM to check on progress with regard to dispatching my clutch assuming that, having paid a fairly substantial £15 TNT carriage charge, I would have it in my hands today.

But I learnt yet another lesson in that, although it was showing as in stock on SRM's system, the clutch still needed "some machining".

So it will be sent today but, because tomorrow is Saturday, TNT therefore won't deliver until Monday  *conf*

I am determined that I will ride the beast at some point before Christmas..................... with or without a clutch!!!!!

Brian

PS No reply from the eBay seller regarding the "wrong" clutch centre yet.....
1955 BSA A10 Golden Flash
Exeter, Devon, UK

Offline RichardL

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I had always believed it was bought in as plungers were only meant to be a stop gap model while BSA developed a swing arm that they did not have to pay royalties on.

Trevor,

Do you mean waiting for a patent to expire? If so, I'm curious who had the patent and how far back it went. I thought I had read somewhere that BSA was being innovative in developing the swingarm frame.

Richard L.

Offline BSA_54A10

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In 1949 Rex McCandless was flogging trumpets  in their own new frame.
BSA bought several of them.
This was the predessor of the Featherbed frame and while BSA was stuff arsing around with board meetings and executive councils & the like, Joe Craig fitted a Norton into one went yep, this is it and hired the brothers to develope the new frame for Norton.
Thus BSA having just introduced the plunger had seen that the swing arm was very much superior.
However BSA made as may bikes in a week as Norton made in a year and Rex , by now a Norton employee ( most likely contractor ) could not allow BSA to use the new frame nor could BSA afford to buy the rights to it, paying royalties.
Thus they used it to base the new frames on by making changes to the steering stem and not fitting the stiffeners on the rear frame loops.
Being one piece it was also cheaper to make & stiffer in operation.
Download drawings of the featherbed and compare them to the swingarm A 10.
The front duplex cradle is identical excepting that BSA used a forged top lug where as Rex used crossover bracing ( and the latter is better ).
Then a change of the rear footpeg lops and viola  a BSA new frame.
Bike Beesa
Trevor

Offline Greybeard

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In 1949 Rex McCandless was flogging trumpets  in their own new frame.
BSA bought several of them. This was the predessor of the Featherbed frame...
...
Then a change of the rear footpeg loops and viola  a BSA new frame.
Absolutely fascinating!
Greybeard (Neil)
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A Distinguished Gentleman Riding his 1955 Plunger Golden Flash

Offline RichardL

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Thanks, Trevor. Very interesting and sent me looking for info about Rex and the featherbed, both with Wikipedia references. The part of the patent that I read makes it sound like it's all based on the frame loops. No mention there of the swingarm, but I suppose it was not the complete patent.

Richard L.

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Trevor 54A10's potted history explains exactly why a lot of us used to think there wasn't a whole lot in it in terms of scratching ability, when we were all young and, ergo, immortal. Personal pride put it down to 'tyres' and a shortage of bhp as to why I ended up crumpled against a dry stone wall in North Wales in about 1974 on a very horrible café racer 'A' while the guy on the tasty modded 99 Dommie made it to the next pub intact  . . .
Drinks aplenty and a-necessary were no consolation for the full rainbow-spectrum bruises - and the prospect of a lot of miles the next day back to E Anglia on a pretty bent beast.
But we laughed then, and now too, 42 years on.
I still think the handling is close, but the ex-Domiracer 650SS that is one of my current prides and joys is one hell of a lot more powerful than my current Beesa (and has better tyres - which proves the old theory then!).
Bill

Offline BSA_54A10

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Rex's bio came out a few years back and is well worth the cover price.
A facinating read, particularly considering he had no formal engineering training.
just a good eye and a better brain.

Post WWII all british motorcycle factories were way too small to make bikes efficiently in the volumes required to be profitable so every corner where a penny could be saved got cut.
Using some one elses patient parts were just not going to happen , no matter how good the end product was Brough . Vincient all went down.
BSA survived because they were vertically intergrated so there was only one profit to be made on the end product.

It is my theory that the various boards of BSA wer convinced that WW III was going to happen any day and thus were not interested in properly developing their motorcycles or manufacturing techniques because any second the motorcycle tooling would have to be replaced by military tooling and there would be money to burn again.
Bike Beesa
Trevor