Suitable gearing set-up.

[1942alexander]

Hi, Very soon I will be building up a Gillott frame into what will be my "bad weather" bike with guards and lights and saddlebag. I'm trying to keep it fairly retro but at seventy, there are difficulties coping with a bike built up like a 1960s machine. For a start, it's back-end is only 126 which limits the size of the freewheel block. As I need a grannie gear of probably 36 to 38 inches, what would be a sensible double chainring and five/six sprockets setup that can be bought, and that would also work well. I would like to use an early Campagnolo rear changer with bar end shifters, maybe having to go for Dura Ace 7700 and use as friction if I can't get campag. Can anyone see any pitfalls in this set-up? Will a rear Campy changer do six sprockets? If it's a block of say 25 to 16 will the chainrings be able to cope with the wide range needed to eliminate duplicating gears by overlap? Is the only sensible way to fit a three ring chainset? Any comments welcome... please.

[tatanab]

Having started riding in the late 60s my first escapade into 10 gears was 48/36 with 14,16, 18,21,26 giving gears in the range 92 to 37 inches. That was with a 5 speed block because the rear end was 120mm wide. Modern riders might be horified at the gap between gears , but we use the technology of the time of course. Campag mechs cope with 6 speed just fine and also the chainring difference I had - ignoring the catalogue specification. Something like this for a block http://www.sjscycles.co.uk/shimano-mf-t ... prod18963/ might be good but would push your period Camapg rear mech quite hard. Even with the 48/36 there is some duplication of gears, but that is not necessarily a bad thing because it reduces double changes.

[thirdcrank]

I've a bike still set up like that. I have a Campag Super Record 5/6 speed rear, Super Record front, both dating from 1980, with campag bar end levers dating from the late 1950's.

For about 25 years, it's had a Stronglight 100 double 48 x 36 with various 6 speed blocks, swapped about according to terrain. The biggest sprocket I've used has been 28T which is still widely avalaible on a 14x28 freewheel. The bottom gear comes in at around 34inches which is within your spec.

I'd say that the Campag bar ends (which I've had over 50 years) are a nightmare. Once upon a time fit for posing, now too much trouble to replace. I imagine that to buy now, they cost an arm and a leg.

The Campag gear works OK but it can be a bit lazy shifting onto the highest gear.

[Brucey]

1950's campagnolo gran sport gears (the ones with the steel and bronze paralellogram) have a short lower knuckle. Later models (NR etc) in aluminium have an elongated lower knuckle. The latter will more easily handle a 26T bottom cog on a 6s freewheel.

You can of course fit 7s into 126mm if you want, or do all kinds of odd things like make your own 6-from-9 setup or w.h.y. on a cassette system (with a little engineering ).

IME a 14-26 or 14-28 freewheel, combined with a 46/28 (or thereabouts) will work very well with old racing mechs and gives a nice range of gears for unhurried touring. For some reason the cycle industry no longer believes that such chainsets are of widespread interest, so you are stuck with buying a used stronglight, a new TA, or building one yourself from a cheap triple.

cheers

[531colin]

Or just go modern....a current road 130mm rear hub will easily get in a 126mm back end, and the worlds your onion.
I much prefer a triple, you can have a huge range of gears with no big steps....even at the front.

[gaz]

A small word of caution with regard to freewheels in the modern age.

There was a time that a freewheel was the very pinnacle of technology for multi-speed bikes and "quality" products were widely available.

That time passed about 20 years ago. Since then new "quality" cycles have been built with freehubs and the freewheel has become an item almost entirely associated with children's bikes and BSOs.

There are still some NOS items from the "quality" era but these tend to be straight through blocks. IRD claim to provide a modern "quality" freewheel for what is now very much a niche market, I've no experience of their product.

[ANTONISH]

It's still possible to buy good quality freewheels - I bought a Regina America a few years ago about 2008 (I think from Spa.) a very nice quality item.

[1942alexander]

Thanks... tatanab. Looking at the gear tables, an ideal set-up to achieve would be 34/50 front and 17 18 19 21 23 25 on the back giving little overlap and a high gear just in the eighties. I wont need a higher gear than that on this bike but would the front changer cope with sixteen teeth difference and would the rear changer cope with the chain? I'm aware that with only twelve gears, and a low of 37 inches or so, the high gears are going to have to go but I wanted to maximise what range I would have by having no, or very little overlap. Many thanks.

[1942alexander]

Or just go modern....a current road 130mm rear hub will easily get in a 126mm back end, and the worlds your onion.
I much prefer a triple, you can have a huge range of gears with no big steps....even at the front.

Thanks 531colin. I have a carbon Orbea Onix with American Classics for racing and training on decent days but when I'm out in the racing jersey, on that bike, I am in training mode. At seventy I now want, sometimes, to look and feel OK just pottering around the lanes for pleasure, rather than have to ride at my limit all the time. I also want to take extra clothing, tools, waterproofs and proper food for the day, hence the saddlebag. Regards.

[531colin]

Me too......



Modern doesn't have to be racy

[Brucey]

I can understand perfectly why you might want period mechs on a nice Gillot; it never looks quite right to me to have a frame like this festooned in myriad sprockets and chainwheels, STI this and indexed the other; something simpler may well be more the thing.

Gaz is quite right; modern freewheels are not what they once were. It isn't all bad though. Of the modern freewheels I have used I can report that Sun Race ones are worth a look; they are certainly cost-effective.

On the minus side they;
- are obviously not of expensive manufacture
- don't have body seals
- might need re-shimming out of the box if you are fussy (I am)
- are not available with spare sprockets
- not every set of ratios you might dream up exists

On the plus side they;

- are so cheap you don't mind binning them when they wear out
- have very smooth bearings
- have pawls that are strong enough
- have hyperglide-esque tooth forms which give really slick shifting.
-use a commonly available extractor tool

I built a bike a while back with such a 14-28 freewheel on it and it has worked really well. 14-16-18-20-24-28 won't suit everyone but it gives a nice set of ratios IMHO.
e.g.

46 ring gives 88.7, 77.6, 69, 62.1, 51.8, (44.4)
32 ring gives (61.7), 54, 48, 43.2, 36, 30.9

-which I could live with, for unladen riding certainly; works nicely on short arm mechs, lots of gears where you need them, not so many where you don't. Only one double-shift unless you are very pernickety.

cheers

[thirdcrank]

... There are still some NOS items from the "quality" era but these tend to be straight through blocks. ...

The vendors also increasingly tend to know that they are in a sellers' market. I still have some Shimano 600 freewheels bought for my stock when Ribble stopped selling freewheels and cleared their stock. (IIRC something like £6 each.)

[BigG]

I am with Brucey, but if you must be retro, then you can probably fit a 7 speed freewheel onto a 126 mm hub (Be careful, some 126 mm hubs were only spaced for 5 speed with reduced dish.) Old Suntour 7-speed freewheels are readily available on ebay, but you will have to accept standard ratios unless you want to mix and match. The only old mechs that will take your wide sprocket and chainring requirements are probably the Campag Touriste or the Simplex and Huret equivalents. I would not recommend any of them as they did not give a very positive change performance even with friction levers and an overshooting technique. IMO, the earliest mech to give you the range that you want was the Suntour VxGT which takes up to a 34 tooth sprocket and about 38 tooth total range. This works extremely well with a 14-17-21-26-32 5-speed and a (for example) 48-43 half step giving 10 nicely spaced gears from 93" down to 36". If a half step doesn't suit you (we all rode them in the 50s), then the same mech will easily cope with a 48-32 or 48-36 chainset and a closer ratio block - say 13-15-17-20-23-26-30. But as Brucey says, go modern and indexed with a 7, 8 or 9 speed cassette on a road hub (130 mm) and modern gears. Almost anything available today will allow this.

[1942alexander]

1950's campagnolo gran sport gears (the ones with the steel and bronze paralellogram) have a short lower knuckle. Later models (NR etc) in aluminium have an elongated lower knuckle. The latter will more easily handle a 26T bottom cog on a 6s freewheel.

You can of course fit 7s into 126mm if you want, or do all kinds of odd things like make your own 6-from-9 setup or w.h.y. on a cassette system (with a little engineering ).

IME a 14-26 or 14-28 freewheel, combined with a 46/28 (or thereabouts) will work very well with old racing mechs and gives a nice range of gears for unhurried touring. For some reason the cycle industry no longer believes that such chainsets are of widespread interest, so you are stuck with buying a used stronglight, a new TA, or building one yourself from a cheap triple.

cheers

Many thanks... Brucey.
If I can fit a seven speed freewheel in that would be great. I've just looked up a couple on Google and they seem to be splined. Is there an adaptor to screw on the old hubs to take the splines? Also I assume some of the sprockets have larger internal diameters than the smaller ones. Will this affect the range you can fit? For example, will a 20T fit where there is normally a 28T? A 14-20 freewheel with a 28/42 setup seems to be perfect, with gears from 38 to 82 in small regular increments. Will it be attainable though? Thanks again.

[1942alexander]

Many thanks for all your help. I apologise to all I have not yet replied to but I have to go out for some food now and wont be back until late, so I'll follow up the ones I've missed tomorrow. Regards.