Gearing?
03-11-04, 10:15 AM
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Gearing?
I've been riding an old "Columbia Commuter III" that I rescued from a dumpster. It was a 3 speed; someone converted it to a singlespeed.
It has a 48 tooth sprocket in front and 19 in back. Is this normal gearing for a singlespeed?
It has a 48 tooth sprocket in front and 19 in back. Is this normal gearing for a singlespeed?
03-11-04, 10:29 AM
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middle gear
48/19 is a 2.52 ratio. Thats typical of a descent 'middle gear' for general purpose riding or training in most areas.
Truly though, only you can answer wether it fits your needs. Ride 2.52 on simliar wheels and see if it works for you.
Truly though, only you can answer wether it fits your needs. Ride 2.52 on simliar wheels and see if it works for you.
03-11-04, 10:51 AM
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Originally Posted by stevo
48/19 is a 2.52 ratio. Thats typical of a descent 'middle gear' for general purpose riding or training in most areas.
The gearing seems a little too high (hard) for me to get a quick start. But if 48/19 is a 'middle gear' it appears that I need to keep working on it and get stronger.
03-11-04, 11:11 AM
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notice I said 'most areas'.
2.52 is pretty light; common among urban riders who sacrficie top-end for quick jumps off the ubiquitious lights. Unless your difficulting in starting is always uphill, then Id say yes, you need to eat your wheaties.
One other possiblity; I'm no 3-speed expert (thats 2 more than any bike I've ever owned), but is it possible that when the hub was 'converted', the internal
gering was left intact? If so, perhaps youre actually pushing much more than 2.52. Quick and dirty way to tell; borrow a multi-speed bike; set the drivetrain to (as close as possible to ) 2.52, and see how it feels relative to your bike.
One other possiblity; I'm no 3-speed expert (thats 2 more than any bike I've ever owned), but is it possible that when the hub was 'converted', the internal
gering was left intact? If so, perhaps youre actually pushing much more than 2.52. Quick and dirty way to tell; borrow a multi-speed bike; set the drivetrain to (as close as possible to ) 2.52, and see how it feels relative to your bike.
03-11-04, 12:19 PM
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[QUOTE=stevo]....I'm no 3-speed expert (thats 2 more than any bike I've ever owned), but is it possible that when the hub was 'converted', the internal
gering was left intact? If so, perhaps youre actually pushing much more than 2.52.
This is a really good point. If the conversion was nothing more than removing the shift cable and the hub is a Sturmey-Archer, then the hub is probably in '3rd' gear. A real easy way to test this is to raise the rear wheel and turn the cranks. Is the cog rotating in lock-step with the hub? If the cog is rotating slower than the hub then the unit is in 3rd gear which (for S-A hubs) means you are probably pushing something like a 3.35:1 ratio....ouch.
Jim
gering was left intact? If so, perhaps youre actually pushing much more than 2.52.
This is a really good point. If the conversion was nothing more than removing the shift cable and the hub is a Sturmey-Archer, then the hub is probably in '3rd' gear. A real easy way to test this is to raise the rear wheel and turn the cranks. Is the cog rotating in lock-step with the hub? If the cog is rotating slower than the hub then the unit is in 3rd gear which (for S-A hubs) means you are probably pushing something like a 3.35:1 ratio....ouch.
Jim
03-11-04, 12:30 PM
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Originally Posted by jimv
Is the cog rotating in lock-step with the hub?
03-11-04, 12:34 PM
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Originally Posted by Chop
Now I've got a real dumb question- What's a "cog"?
03-11-04, 12:36 PM
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Originally Posted by Schiek
sprocket=cog
