Author Topic: 357 cam/Valve spring change  (Read 413 times)

Offline Henry

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357 cam/Valve spring change
« on: 21.06. 2017 14:54 »
I have a super rocket with big valve head high comp pistons & 357 cam do I need to change springs or not ?
I have a super rocket fitted with b/ valve head ,357 cam,9.1 pistons do I have to change valve springs(I know valve clearances are different) regards Henry

Online RichardL

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Re: 357 cam/Valve spring change
« Reply #1 on: 21.06. 2017 18:23 »
Henry,

Welcome to the forum.  *welcome* Maybe you could get over to Pictures, Stories and Introductions and tell us a bit about yourself, like how you got into BSAs, other bikes you play with, about where you're located, mother's maiden name and bank account number. (OK, maybe not those last two.) Also, pictures are always appreciated.

I'm not the last word on this, but here is what SRM says for Super Rocket and RGS:

67.0357 Camshaft ;Check fitted valve spring outer length to be no less than 1.400 inch ( 35.5mm) also check valve springs at full lift and make sure they are not coil bound and can be compressed at least another  0.080 inch ( 2.0mm).
Part Number: SRMSP7
Dimensions:
8 × 10 × 5 cm
Weight:
0.29 kg
Bike Model:
A7 / A10

Hope this helps.

Richard L.
Plan on signing up for the world-wide 2020 DISTINGUISHED GENTLEMAN'S RIDEon September 27, 2020 (if it's not cancelled and we are free to move about by then). Watch website at https://www.gentlemansride.com for details.

Offline duTch

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Re: 357 cam/Valve spring change
« Reply #2 on: 21.06. 2017 22:40 »

 hola Henry- welcome along....

 
Quote
do I need to change springs or not ?
   *dunno*    maybe some more information will help?

 Do you think they're the wrong springs? Are the springs dong something untoward ? Is the bike together and funtional?

 Pictures always help
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Online chaterlea25

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Re: 357 cam/Valve spring change
« Reply #3 on: 21.06. 2017 22:47 »
Hi
Alloy head 650's use different valve hardware than iron 650's or iron/ally 500's

John
1961 Super Rocket
1963 RGS (ongoing)

Online RichardL

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Re: 357 cam/Valve spring change
« Reply #4 on: 21.06. 2017 23:38 »
Hi
Alloy head 650's use different valve hardware than iron 650's or iron/ally 500's

John

Ah, yes. SRM has the info for those other springs on their site, as well. I only copied the Super Rocket and RGS info.

Richard L.
Plan on signing up for the world-wide 2020 DISTINGUISHED GENTLEMAN'S RIDEon September 27, 2020 (if it's not cancelled and we are free to move about by then). Watch website at https://www.gentlemansride.com for details.