Freewheel fixed conversion

willbevan

Hi all,

Having a play concerting an older shimano 6 speed freewheel to a fixed.

Now my question is:

I have a vague recolection that the mountings on the wheels for the freewheels were interchangable, i.e. Campag and shimano would fit onto the same block.

Reason being i've been looking around ebay etc to find a fixed sprocket (realise i need spacers etc) and one ive seen mentions a '1/8 English threading'

http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... :middle:uk

Now is that compatible with an old 6 speed shimano?

Thanks

Will

LeighB

I think the answer is yes. I have Campag hub which has the British thread. This hub has had a Regina freewheel, Shimano freewheel and Shimano Dura Ace track sprocket fitted at various times. The only other thread for old type hubs is Italian. I would be carefull buying un-branded sprockets, you can get Shimano track sprockets from Ribble Cycles for £11.45. The 1/8th may refer to the width of the teeth; two sizes are available 1/8th and 3/32nd. I run 3/32nd which is normal derailleur chain, 1/8th is thicker track chain. My road gearing is 42 x 15 which is about 74'' and ok for me as I live in quite a hilly area.

willbevan

Leigh, thank you very much for the reply, just the info i needed

willbevan

Quick query, could a 1/8 chain be used with a typical chainring that did have a 6 speed chain on before?

meagain

Yes, but not vice versa!

As to fixed sprockets/hub thread, apart from strange French (I think) threading on a sprocket I've never come across any incompatabilty.

LeighB

1/8th chain will run (sloppy with lots of side play) on a 3/32nd sprocket; but you cannot fit 3/32nd chain on a 1/8th sprocket. When I did my conversion I fitted a new Stronglight chain ring to an old road crank set, if your chain set is the common 130 mm BCD (bolt circle diameter) Shimano type the sprockets are not too expensive.

willbevan

is it advisable to run a 1/8 chain on a fixed wheel? if so what would be the reason (sorry asking lots of questions)

LeighB

The only reason I used 3/32nd chain was cost; the front chain rings were cheaper in 3/32nd and I had a spare new 3/32nd chain. I have read that 1/8th chain is better wearing but have no experience of using it. My 3/32nd fit up works fine and has been used through the winter with no problems; if it did wear out I could replace the chain and sprockets (3/32nd) for less than £35.

meagain

FWIW, I think that all 1/8th is best, then all 3/32nd, any "combinations" of the 2 sizes last!
Although 1/8th chain on smaller sprocket AND ring allows a bit more leeway with chain line.

Well, that's one opinion!

willbevan

hmmm can see what you mean with chain line, i am playing with the 6 speed freewheel and just adjusting the cog manually to see what setup i would like, i have already noticed if you dont have the chainline right the gear skips if it isnt tight and close....

another silly question, i have a tool to break a chain, and the quick line thing, but what happens if you want to lengthen the chain with the original peices (presuming its not worn)

Thanks

Will

redvee

Just to chuck a spanner in the works the set-up on my SS GT is an Haro 46t BMX 1/8" Chainring, 16t 3/32" sprocket and joined up with a Sram PC48 3/32" chain.

meagain

" i have a tool to break a chain, and the quick line thing, but what happens if you want to lengthen the chain with the original peices (presuming its not worn) "

Use the tool to re-break the chain at point away from the quick link and then reinsert the required number of links?

willbevan

unless im being dense how can you reinsert the pin, as i can't get the prong from the tool to keep it in place and push it respectively??

meagain

You never push then ALL the way out! Just enough to twist the plates apart.

willbevan

ah thats where im going wrong :S doh