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Retro 'rebuild'. Conflicting with metrication

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Durban-Road:
A slight dilemma;

If I decide to get my bike back on the road it is going to need new tyres, inners and a new derailleur  gear. I would probably buy a new chainring/s to go with the new gear. The problem is, would a modern gear work with the existing 6 sprocket cassette?
If not, would a modern cassette fit onto the threads of my old hub (1960s)?

These really are the only new parts I would need, such is the condition of the bike at present.

Any advice would be welcome, even ideas on the new hub gears.

Thanks in anticipation.

JA  :D

rualexander:
Modern freehub cassettes won't fit your 1960s freewheel hub, different design.
You can still find a few 6 speed screw on freewheel type gear clusters e.g. : http://www.sjscycles.co.uk/category-Freewheels--6-Speed-78.htm
A modern rear derailleur (e.g. Deore or similar) should work ok with what you already have though.

mateusz:
As indicated above, casette would not work, as your hub is for screw-on freewheels. On freewheels, see the article by late Sheldon Brown. 7sp freewheel should fit your bike, it would surely fit if the rear wheel spacing is 126mm, but I have squeezed 7sp freewheel on a 120mm Raleigh frame too.
Your gears are not indexed anyway, so no problems there.
8sp chain would work OK, Sachs/SRAM PC68 is the best (and looks nice, too).

I would start with getting the new inner tubes and tires (if they have disintegrated, but try first!) and a quick clean of the chain. It might work OK with old gears and all. After all, you have nothing to lose if you use the existing stuff. If it is all rusted solid, go ahead, buy a new chain and a freewheel.
Usually there is no reason to change the chainrings. If they are steel, they will last forever. If they are alloy, they will last well in excess of 30k miles (I just cleaned and checked mine). Getting the chainrings, apart from not being necessary, might me more difficult then finding a suitable freewheel. Chainring bolt hole spacing standards vary, sometimes they are not replacable at all, and then you will need to find the right set of (expensive) cranks to match your BB spindle. You will end up changing everything (trust me I've been through that path before, many times), better ride what you have!
Mateusz (ex compulsive carboot 15 quid-a-piece bike buyer)

Durban-Road:
Thanks Mateusz,

Tyres are a definite requirement.
Fortunately the bike is not seized up at all. The gears work well enough, but the last time I rode the bike,  occasionally pedalling had no effect on forward motion. As if the chain was slipping between sprockets. Hence the possibility of a new rear gear.  The bike has an ally, cotterless crank set which was fitted along with a new BB, just before the bike was put in store.

Apart from the tyre problem and a few scratches, the bike is in good fettle. Maybe I'll get rid of the spongy rubber I put on the bars, and replace with some original tape. A wider pair of pedals wouldn't go amiss either!

So maybe  there isn't so much work as I envisaged, to get it back on the tarmac.
Thanks again for the advice everyone.
 
Regards
  :)

mateusz:

--- Quote from: Durban-Road on August 09, 2010, 11:15:44 am ---occasionally pedalling had no effect on forward motion. As if the chain was slipping between sprockets. Hence the possibility of a new rear gear. 

--- End quote ---
That may well be, one thing you could try though is to squirt some WD40 from the back of the freewheel (preferably removed to avoid diluting grease in the hubs) - the effect you are describing could be a soft freewheel failure coming from gunked up ratchets inside. WD40 could free them. Sprocket wear would be immediately visible in any case - look for hook-shaped, assymetrical teeth.
I went through seven 10-speeders and a few of junk MTBs in my times, the worst of the latter was so rusty that both brake cables eventually snapped (kids don't try this on Brighton hills), painted white with a brush, but Chiquita Bananas sticker convinced me and i bought it for a fiver.
Mateusz

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