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Rohloff Internal Hub Gears / Re: Smallest Chainring?
« Last post by Thomas777 on April 27, 2024, 11:47:25 pm »PH, now that's an idea!
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52
Rohloff Internal Hub Gears / Re: Smallest Chainring?
« Last post by PH on April 27, 2024, 08:04:01 pm »My wife's bike,with 26" wheels, currently has a 38-16. We will be cycling across the US and in Idaand Washington there are some long steep grades. She has ridden this combo for a while. So since we are riding east to west maybe her legs will be strong enough when we get to the mountains!Sounds like a great adventure.
Thanks for your responses!
You could take a couple of chain links and a 21T sprocket, change it when you come to the hills. With a snap ring it's much easier to change the sprocket than the chainring. I know of someone who cycled across the US on a single speed, they changed sprockets a couple of times, though I think they had a tensioner so didn't have to bother changing the chain.
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Rohloff Internal Hub Gears / Re: Smallest Chainring?
« Last post by JohnR on April 27, 2024, 06:22:28 pm »A bigger sprocket should be cheaper than a smaller chainring and a pair of bigger gears is marginally more efficient than a pair of smaller gears with the same ratio. Changing the sprocket from 16T to 18T is approximately the same as one gear step on the Rohloff hub (as is changing the chainring to 32T). However, if thinking of changing the chainring you also need to check the size of the spider. If it's 130mm BCD then 38T is the minimum chainring size.
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Rohloff Internal Hub Gears / Re: Smallest Chainring?
« Last post by Thomas777 on April 27, 2024, 05:59:46 pm »My wife's bike,with 26" wheels, currently has a 38-16. We will be cycling across the US and in Idaand Washington there are some long steep grades. She has ridden this combo for a while. So since we are riding east to west maybe her legs will be strong enough when we get to the mountains!
Thanks for your responses!
Thanks for your responses!
55
Bikes For Sale / Re: Thorn Brevet
« Last post by PH on April 27, 2024, 05:41:08 pm »Not for me, though I lusted after one 20+ years ago.
Who might it be for? An idea of the size might narrow it down
Who might it be for? An idea of the size might narrow it down
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Was it you? / Re: Mercury meets Nomad
« Last post by PH on April 27, 2024, 05:38:57 pm »Very different bikes, though they both have the distinctive Thorn look.
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Rohloff Internal Hub Gears / Re: Smallest Chainring?
« Last post by PH on April 27, 2024, 05:36:41 pm »30T, assuming that fits on the cranks.
But what's the purpose of the question? if you're looking for lower gears, then changing the sprocket might be a better way to go, cheaper and kinder on components, unless there's some reason you can't. 36/19 is going to be close to 30/16, either will give a really low gear, about 14" on a 700c wheel. OK on a trike, but I can't pedal that low and balance, plus I'd be spinning out on the top gear.
But what's the purpose of the question? if you're looking for lower gears, then changing the sprocket might be a better way to go, cheaper and kinder on components, unless there's some reason you can't. 36/19 is going to be close to 30/16, either will give a really low gear, about 14" on a 700c wheel. OK on a trike, but I can't pedal that low and balance, plus I'd be spinning out on the top gear.
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Rohloff Internal Hub Gears / Re: Smallest Chainring?
« Last post by mickeg on April 27, 2024, 05:02:32 pm »I assume this is for a Rohloff bike.
Most on this forum use a 17T sprocket, as that was standard from Thorn.
I use a 16T which was the standard shipped with most hubs. For touring, I use a 36T chainring, that gives me a low gear that at 3.5 mph has a cadence of about 72 with my 559X57 tires. Slower than 3 mph, I walk the bike.
But for riding around near home where the most weight on the bike is a bag of groceries, I use a 44T sprocket. That gives me a much nicer range of gears for unladen riding.
I add or subtract four links when I change chainrings, use two quick links when using 44T.
Rohloff does not specify teeth, they specify a ratio of chainring teeth divided by sprocket teeth. Do a word search for ratio at this link.
https://www.rohloff.de/en/experience/technology-in-detail/specifications
My 36/16 ratio is 2.25 for touring, or 44/16 ratio is 2.75 for use around home.
Most on this forum use a 17T sprocket, as that was standard from Thorn.
I use a 16T which was the standard shipped with most hubs. For touring, I use a 36T chainring, that gives me a low gear that at 3.5 mph has a cadence of about 72 with my 559X57 tires. Slower than 3 mph, I walk the bike.
But for riding around near home where the most weight on the bike is a bag of groceries, I use a 44T sprocket. That gives me a much nicer range of gears for unladen riding.
I add or subtract four links when I change chainrings, use two quick links when using 44T.
Rohloff does not specify teeth, they specify a ratio of chainring teeth divided by sprocket teeth. Do a word search for ratio at this link.
https://www.rohloff.de/en/experience/technology-in-detail/specifications
My 36/16 ratio is 2.25 for touring, or 44/16 ratio is 2.75 for use around home.
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Rohloff Internal Hub Gears / Smallest Chainring?
« Last post by Thomas777 on April 27, 2024, 12:37:22 pm »Wondering what the smallest chainring some of you are using with a 16t sprocket?
What is the smallest that can be used?
Thanks!
What is the smallest that can be used?
Thanks!
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Bikes For Sale / Thorn Nomad Mk2 565M For Sale
« Last post by Inbred on April 27, 2024, 08:35:01 am »Thorn Nomad MK2.
Thorn 969 frame. Size 565M.
Rohloff speed hub 14spd gears. Thorn crankset. Shimano SPD pedals.
Zac 79 rims. Shimano Deore front hub. Schwalbe Mondial tyres.
Shimano XT V-brakes & levers.
Thorn FFT bars. Ergon GP5 grips. Uno Stem.
Brooks B17 saddle. Thorn seatpost.
Thorn expedition rear rack.
Profile design bottle cages X3.
SKS full-length mudguards.
£1800 ono
https://www.facebook.com/marketplace/item/1002770678136514/
Thorn 969 frame. Size 565M.
Rohloff speed hub 14spd gears. Thorn crankset. Shimano SPD pedals.
Zac 79 rims. Shimano Deore front hub. Schwalbe Mondial tyres.
Shimano XT V-brakes & levers.
Thorn FFT bars. Ergon GP5 grips. Uno Stem.
Brooks B17 saddle. Thorn seatpost.
Thorn expedition rear rack.
Profile design bottle cages X3.
SKS full-length mudguards.
£1800 ono
https://www.facebook.com/marketplace/item/1002770678136514/