Author Topic: Valve Spring Length  (Read 1707 times)

Offline alanp

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Valve Spring Length
« on: 16.11. 2009 18:59 »
Does anyone know the correct free length of the valve springs on a Super Rocket/RGS? I have two documents with lengths listed and neither of them bear any similarity to mine. Mine are about 2" and 1 13/16th" long. Thanks.
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Online trevinoz

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Re: Valve Spring Length
« Reply #1 on: 16.11. 2009 22:37 »
Alan,
              I have a new set of Terry's springs.
Outer is 2.125" and inner is 1.985"
The set number is VS463.
I hope this helps.
   Trev.

Offline dpaddock

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Re: Valve Spring Length
« Reply #2 on: 17.11. 2009 15:05 »
Bacon's Twin Restoration book has the free lengths at 2.000" (inner) and 2.125" (outer). Three decimal places implies a level of precision which I believe is not intended.

David
David
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Offline alanp

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Re: Valve Spring Length
« Reply #3 on: 17.11. 2009 16:06 »
Trev/Dave, thanks for the info. I reckon my springs need replacing! Gone a bit saggy like me!!
Alan
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Online bsa-bill

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Re: Valve Spring Length
« Reply #4 on: 17.11. 2009 16:37 »
Hi Alan 2.125" (outer). Three decimal places implies a level of precision which I believe is not intended.

Might well have been intended as it's an eighth of an inch, I find it curious as to how they came to mix  dimensions between metric and British

All the best - Bill
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline Desburnett

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Re: Valve Spring Length
« Reply #5 on: 17.11. 2009 18:00 »
Hi Alan 2.125" (outer). Three decimal places implies a level of precision which I believe is not intended.

Might well have been intended as it's an eighth of an inch, I find it curious as to how they came to mix  dimensions between metric and British

All the best - Bill

2.125" is the decimal equivalent of the fractional 2 1/8" both Imperial (British units of measurement) if it were metric it would be expressed as 53.975mm or rounded to 54mm

Online bsa-bill

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Re: Valve Spring Length
« Reply #6 on: 17.11. 2009 18:41 »
Quite correct Desburnett, in this case I was merely making the point that 1.125 is an eighth.
 I was thinking on a more general level re the metric remark , capacity for instance.
OTOH I have read that Japanese makers use or used cycle thread, it's a funny old world

All the best - Bill
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline alanp

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Re: Valve Spring Length
« Reply #7 on: 17.11. 2009 19:54 »
Bill, slightly off/on subject, talking inch and metric threads, on this island we tend to swop about from one to the other without much thought but this is not the case in mainland Europe. We used to have to redesign US machinery to use metric threads and bearings for machinery we built and shipped to Europe or we couldn't expect maintenance to be carried out properly because their spanners wouldn't fit and replacement inch bearings weren't available down the road. If we didn't redesign for metric they'd go to our competitors. My spanners and sockets are all colour coded so I know which type I'm looking for or life could get stressful!
Alan
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