Question for gearing gurus
07-12-24 | 07:58 AM
#1
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From: Elwood Indiana
Bikes: they change so much I'm tired of updating this
Question for gearing gurus
Just got back from a nice relaxing ride. After a few hours I realized I never shifted. That got me thinking the gearing would make a perfect single speed. So how can I turn a 36-20 gearing into a single speed? Thanks
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07-12-24 | 07:59 AM
#2
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From: Elwood Indiana
Bikes: they change so much I'm tired of updating this
Well I should’ve searched before I typed this thread. I had no idea they made 20t freewheels. Sorry
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07-12-24 | 08:25 AM
#3
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From: Fredericksburg, Va
Bikes: ? Proteous, '65 Frejus TDF, '73 Bottecchia Giro d'Italia, '83 Colnago Superissimo, '84 Trek 610, '84 Trek 760, '88 Pinarello Veneto, '88 De Rosa Pro, '89 Pinarello Montello, 'Litespeed Catalyst'94 Burley Duet, 97 Specialized RockHopper, 2010 Langster
If you don't like the tooth count, you can always calculate the gear inch and work backwards. So you are at 50 gear inches.
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07-12-24 | 10:05 AM
#4
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From: South shore, L.I., NY
Bikes: Trek Emonda SL7, Cannondale Topstone, Miyata City Liner, Specialized Chisel, Specialized Epic Evo
I saw a bike converted. He used PVC pipe inside and out of where he put the single cog on the cassette body, so as to hold the cog in place. Then got rid of one of the chainrings and both derailers, sized the chain accordingly. It helped that it was an older Italian steel frame with slots for the axle, so he was able to set the chain tension.
07-12-24 | 11:39 AM
#6
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From: Elwood Indiana
Bikes: they change so much I'm tired of updating this
07-12-24 | 02:55 PM
#8
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From: Long Island, NY
Bikes: Trek 800 x 2, Schwinn Heavy Duti, Schwinn Traveler, Schwinn Le Tour Luxe, Schwinn Continental, Cannondale M400 and Lambert, Schwinn Super Sport
07-12-24 | 06:31 PM
#9
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From: Usually on one of my bikes
Bikes: '93/'94 Yokota Grizzly Peak (MTB), 2021 Bear Bike Armata (Track), 2021 Schwinn Kedzie (SS)
While this is for fixed gear https://www.surplace.fr/ffgc/ it is applicable to single speed and gives a chart of equivalent gears. If you wanted to use small gears, 36/20 would be the same (within 2%) as 30/17.
Hope it helps,
SM
Hope it helps,
SM
Last edited by Steel Monkey; 07-12-24 at 07:13 PM. Reason: added information
07-13-24 | 06:44 AM
#10
feros ferio
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From: www.ci.encinitas.ca.us
Bikes: 1959 Capo Modell Campagnolo; 1960 Capo Sieger (2); 1962 Carlton Franco Suisse; 1970 Peugeot UO-8; 1982 Bianchi Campione d'Italia; 1988 Schwinn Project KOM-10;
Assuming the 36/20 combination gives you a fairly straight chainline, why not simply shorten the chain (assuming horizontal dropout slots) and remove the shifting apparatus? That way you can trivially restore full functionality when you either decide to sell the bike or rediscover the magic of multiple gear ratio options at your command.
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"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069
"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069
07-13-24 | 09:22 AM
#11
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From: Elwood Indiana
Bikes: they change so much I'm tired of updating this
Assuming the 36/20 combination gives you a fairly straight chainline, why not simply shorten the chain (assuming horizontal dropout slots) and remove the shifting apparatus? That way you can trivially restore full functionality when you either decide to sell the bike or rediscover the magic of multiple gear ratio options at your command.
It’s on my Trek 728 and I’m not changing anything. I just thought it would be fun to build a nice super light single speed on the mornings when the wind is calm. In most days I need the extra gears. Why do we do 90% of the stuff we do with bikes? Because we can and it’s fun.
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