Author Topic: Spring retainers  (Read 2202 times)

Offline JulianM

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Re: Spring retainers
« Reply #15 on: 25.06. 2012 09:53 »
Thanks Dutch,
Appreciate as much info as possible.  I have a Commando so will investigate on that also.  I would rather not make a new primary cover but maybe if needed.
Or options for a stronger clutch that people have used?

Julian.

PS.
Will post a new topic on the car in the right place, when I have some more time, in a few weeks prob.
55 Ariel HS mk1,
58 BSA Super Rocket Scrambler special,
60 BSA Gold Star, Jim hunter desert racer,
64 Norton N15CS,
65 Triumph TR6 SS,
66 Triumph Bonneville,
71 AJS Stormer,
71 BSA Rocket 3,
71 Laverda 750SF,
71 Laverda/Egli 750SF, Race bike,
73 Norton Commando 850,
74 Moto Morini 3-1/2 Sport,
74 Bultaco Sherpa 350,
76 Beta Cross 50,
77 Moto Guzzi Le Mans Mk1,
80 Ducati 900 MHR,

Offline cus

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Re: Spring retainers
« Reply #16 on: 26.06. 2012 22:58 »
G'day Julian,
I had these made up, mainly because I found the new stock setup I ordered
seem to make the tappet fowl on the rocker cover,
the bike had alloy after market ones fitted when I got it, but they were quite old & didn't want to re-use them.
Have done quite a few thousand miles on this setup.



regards, Cus

adm edit: photobucket link fixed.
56 G/Flash project

Offline JulianM

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Re: Spring retainers
« Reply #17 on: 27.06. 2012 08:45 »
Hi Cus,

Thanks for that.  I think I will be making something similar.
Irritatingly, I had ally caps etc on my old head before I changed it to the twin carb head.
AND THEN stupidly swapped the complete thing for an empty "Square Four" Mk2 head   *sad2*  Duuur!
Thinking that I could buy it all new easily enough, "Everything must be available for an A10, mustn't it?"  *smile*

Best regards,
Julian
55 Ariel HS mk1,
58 BSA Super Rocket Scrambler special,
60 BSA Gold Star, Jim hunter desert racer,
64 Norton N15CS,
65 Triumph TR6 SS,
66 Triumph Bonneville,
71 AJS Stormer,
71 BSA Rocket 3,
71 Laverda 750SF,
71 Laverda/Egli 750SF, Race bike,
73 Norton Commando 850,
74 Moto Morini 3-1/2 Sport,
74 Bultaco Sherpa 350,
76 Beta Cross 50,
77 Moto Guzzi Le Mans Mk1,
80 Ducati 900 MHR,

Offline cus

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Re: Spring retainers
« Reply #18 on: 27.06. 2012 22:48 »
G'day Julian,
If you have trouble finding them, I can send
you one of my old ones for a pattern,
they were called "Dural Retainers" if thats
any help,

regards, Cus
56 G/Flash project

Offline Rocket Racer

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Re: Spring retainers
« Reply #19 on: 28.06. 2012 04:59 »
 Out of interest, what revs do people usually use on the RGS in moderate race trim?

The block will be point "touch" scanned, to give a rough measurement guide and then designed for CNC machining after that.  I want it to resemble the stock part but it doesn't need to be an exact copy, just not look out of place.  The base flange will be heavily reinforced and the main barrels will be a lot thicker to cope with not only the extra bore size but the power output of a 750 on 10.5:1 cr  (whatever that turns out to be)  Material will probably be 6061 or 7075-T6 but prob the former.   Will start the process properly in early July as my schedule is a bit full until then.

Regards and thanks all for making me welcome.
Julian


Eddie Dow quoted max power at 6800, max safe continuous 7000, with 7200-7400 through middle gears.
My experience is that 7500 comes up readily with a 357 cam and stock pipe and pays to watch for over revving.
In 1953 Kiwi Erle Culver used to reckon his gold flash running a 358 cam pulled 8k easily, although the small journal crank only lasted two seasons.

If you are in a position to knock up alloy barrels would be very interested. Its hard work chasing T140's and 850 Commandos with an A10 on the track!

I still run an o'ring single row primary but do change it regularly.
 
A good rider periodically checks all nuts and bolts with a spanner to see that they are tight - Instruction Manual for BSA B series, p46, para 2.
New Zealand

Offline JulianM

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Re: Spring retainers
« Reply #20 on: 28.06. 2012 07:40 »
Interesting with the revs quoted,  about what I was thinking.  I want to be able to buzz to 7500 if need be but doubt it will be needed much.
Looking at the crank and other bits it all looks robust enough. Certainly for short durations and intermittent use that I intend anyway.
My bike originally was once a Super Rocket and has the big crank and now the usual SRM roller conversion and uprated oil pump etc.
Good to know there are no real terrors other than the barrels. 
The only gauge it will have will be a rev counter anyway. Just so I can keep an eye on it!   

Prepping the frame at the moment and adding some strength and repairs here and there.

Will add a build thread after the weekend I think as this one is starting to get that way already.  *smiley4*

Regards,
Julian
55 Ariel HS mk1,
58 BSA Super Rocket Scrambler special,
60 BSA Gold Star, Jim hunter desert racer,
64 Norton N15CS,
65 Triumph TR6 SS,
66 Triumph Bonneville,
71 AJS Stormer,
71 BSA Rocket 3,
71 Laverda 750SF,
71 Laverda/Egli 750SF, Race bike,
73 Norton Commando 850,
74 Moto Morini 3-1/2 Sport,
74 Bultaco Sherpa 350,
76 Beta Cross 50,
77 Moto Guzzi Le Mans Mk1,
80 Ducati 900 MHR,

Online muskrat

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Re: Spring retainers
« Reply #21 on: 28.06. 2012 07:55 »
G'day Julian, watching this thread and anything else you put up with interest.
Yep, 7500 quite regularly on the A7SS racer (357, lightened flywheel, etc, etc)  cranks were a problem after I stopped the top end coming off (through bolted). The LJ crank in it now seems to cope but the comp is down from 13:1 to 10:1.
 If only I had a set of those barrels 10 years ago.
If any one makes a set of titanium retainers I'd be interested in a set. Not racing now but always looking at mods for the cafe (ex racer).
Cheers.
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7