Author Topic: 1962 BSA A10 Super Rocket Pistons  (Read 1871 times)

Online chaterlea25

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Re: 1962 BSA A10 Super Rocket Pistons
« Reply #15 on: 08.03. 2017 00:12 »
Hi Trev,
Yes I Know that but neglected to add it into the conversation *red*

I have a mint low mileage 1549 head destined for my RGS,
Of course some "knowledgable" twat will tell me its Wrong *razz*
Now should I swap the 1571 head from my SR to the RGS  *????*  *dunno*

John
1961 Super Rocket
1963 RGS (ongoing)

Online trevinoz

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Re: 1962 BSA A10 Super Rocket Pistons
« Reply #16 on: 08.03. 2017 20:25 »
I would use the 1549 head as I am pretty sure that was fitted to the RGS as well as the SR.
Anyway, said "knowledgable twat" would need a mirror the tell what you have.
I am sure that you can handle the "experts", John.

Offline bl**dydrivers

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Re: 1962 BSA A10 Super Rocket Pistons
« Reply #17 on: 19.03. 2017 05:42 »
Hi all, it turns out the Super Rocket was fitted with 8.5:1 ratio as standard and was lucky enough to have sourced NOS BSA +.040" pistons. Now can have my bores suited for the pistons.

None of my sources mentioned 9.1:1 ratio.

Thanks

Online JulianS

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Re: 1962 BSA A10 Super Rocket Pistons
« Reply #18 on: 19.03. 2017 11:06 »
The 1960-62 parts book piston chart shows piston numbers and compression ratios.

Parts service bulletin G23 from March 1963 shows a change of piston for the SR and RGS to a common piston but does not say what ratio the new piston was.

And the Hepolte catalogue of the same time gives more choice of 8:1, 8.5:1, 9:1 or 10.5:1 compression.


Online edboy

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Re: 1962 BSA A10 Super Rocket Pistons
« Reply #19 on: 19.03. 2017 20:02 »
i remember finding the flat top 8.5/1 were unavailable in the 80,s. only the dome 9/1 which were considered inferior due to overheating and accurate timing problems with a mag. back then almost every bsa shop i frequented recommended 7.5/1 flat tops for an easier life.

Offline worntorn

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Re: 1962 BSA A10 Super Rocket Pistons
« Reply #20 on: 24.03. 2017 03:19 »
I recall reading on the BSA page that there were three types of Super Rocket each year, UK, East Coast USA ( same as export bikes to other countries) and finally West Coast USA as demanded by the big Californian BSA Dealer, Hap Alzina.
The UK bikes had less chrome than the East Coast USA bikes but the same compression ratio. I believe it was 8.3 to on in 1962, however different articles list slightly different numbers.
The Hap Alzina bikes after 61 were 9 to one. They also had the peanut tank, more chrome yet and cowhorn bars, all to suit the California Hot Rod style of the day.

Of course my memory could be way off on this. I did quite a bit of reading on that site about two years ago when shopping for a Super Rocket.

Glen