21" spoke length for 1958 30CS model

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OEW591
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Re: 21" spoke length for 1958 30CS model

Post by OEW591 »

I've just had the 21" front wheel from my G80CS rebuilt by John Bolton of Workshop 14. Rim and spokes came from Central Wheel at Coleshill, Nr Birmingham. They should be able to help.
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Harry44
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Re: 21" spoke length for 1958 30CS model

Post by Harry44 »

GOLDSTAR wrote:Harry, I would have thought that if the hubs are full width then you are correct but half width surely the side without the brake drum would be longer. kind regards
Probably but only by a tiny amount because they will still be tangential. Picture the spoke coming out of the nipple in the rim (insert joke of your choice) imagine the other end of the spoke entering a small hub, then move that end of the spoke away from the centre of the hub using the nipple as a pivot. It can now go to a larger hub without changing its length.

However some rims are not central on the hub being dished (bicycles with derailleur gears for example) this may change the length from one side to the other.
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clive
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Re: 21" spoke length for 1958 30CS model

Post by clive »

The flaw in your argument Harry44 I believe is that the spokes on both sides show the same pattern. More particularly if we refer to the 1952 parts list this has the length of the spokes recorded. Single sided front hub 20 spokes at 5 3/16 And 20 spokes at 6 1/4. If you go to a 21 inch wheel the same difference in length is maintained 8 1/8 and 9 3/16. I hope this continued discussion has not obscured my measuring of the spoke lengths for a 21 inch full width hub as requested by the original poster David (Matchless) which now appears a page back.
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Mick D
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Re: 21" spoke length for 1958 30CS model

Post by Mick D »

Hi

Increasing the spoke length by 3" would require a rim of around 24" ;)

Regards Mick
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clive
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Re: 21" spoke length for 1958 30CS model

Post by clive »

My apologies the correct pairing is 5 3/16 And 8 1/8 for the 19 inch wheel and 6 1/4 And 9 3/16 for the 21 inch.
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GOLDSTAR
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Re: 21" spoke length for 1958 30CS model

Post by GOLDSTAR »

hi Clive, where does he mention a full width hub, I must have missed it? kind regards
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clive
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Re: 21" spoke length for 1958 30CS model

Post by clive »

1958 30CS is in the title, standard fitment is the full width hub. Keep up at the back there and no snoozing :rofl:
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GOLDSTAR
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Re: 21" spoke length for 1958 30CS model

Post by GOLDSTAR »

Ah Clive, assumptions! my 1954 spring twin should have a 500 twin in it but it ain't houses a s/s G80cs lump. er most kind regards
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Re: 21" spoke length for 1958 30CS model

Post by matchless »

Hi Goldstar, As stated, I have 1958 front and rear full width alloy hubs. The rear hub takes thicker spokes and has the 5 steel pins (no rubbers) as it is an original CS hub. Otherwise the alloy hubs have the same dimensions as any of the 55-62 (non rubber) hubs.
The rear alloy hub is a smaller diameter than the front hub. Therefore the spoke lengths are quite different Harry. Of course the spokes are different for the steel hubs, but that's not we are looking for here.

Thanks Clive for measuring your spoke.
Hi Mick, I have access to 19" wheels and spokes.

The bike I am building is a 1958 30CS and I need to find out the length of the 21" front spokes for that year and model as this is not listed in any of the literature.
Surely someone has overcome this problem before? Once I have the dimension then I will order the spokes and re-lace the wheel myself. The wheel builders I have spoken to all want to do the job themselves (Where's the fun in that?).
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Re: 21" spoke length for 1958 30CS model

Post by Mick D »

Hi

I use this company for my wheel building supplies - never been disappointed yet:

https://www.devonrimcompany.com/classic ... 1-off-road

Don't know if shipping precludes this option.

Regards Mick
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