Hub gear range?

[nirakaro]

I'm tempted by the idea of trying a hub gear. However my present derailleur setup - 44-34-22 front, 11-34 rear - gives me a ratio between top and bottom gears, if I've done my sums right, of about 6.2:1, and I use the full range. It looks to me as if the widest range I'll get with a hub gear is about 4:1, which I don't think would be enough for me. What are my options, if any?

[Brucey]

options?

1. Rohloff (526% range)

2. Any hub gear with a tensioner and a double (or triple) chainring. Shimano Alfine hubs are designed to be used in this way, and alfine tensioners (there are two models, one for this use) will work with other gears.

3. Any hub gear with a double (or triple) sprocket fitted. Older SA hubs will take two sprockets easily, other hubs may need something making up.

4. SRAM dualdrive, (and similar SA hub) offer a cassette + 3s hub in one package.

BTW, %age ranges can be a bit misleading, in that (say) a 17" to 100" range is 588% but a 19" to 100" range is 'only' 526% and a 19" to 95" range is only 500%. IMHO the 'extra 50% (or 88%) range' doesn't actually get you that much in the former case.

[edited to correct percentages...hope I got it right this time... ]

cheers

[Mick F]

19" to 95" is 500%

19 x 5 = 95

[Brucey]

oops.... I may have pushed the wrong buttons there... thanks Mick!

(I shall edit my post accordingly)

cheers

[Mick F]

That's ok!
Actually, I wanted to get back on my hobby horse regarding percentages and their misuse.

19" to 95" is 400%. ie a quintupling of ratio.

100% increase is a doubling ............ but I digress.

[pwa]

Pricey, I know, but Rohloff gives a range of about 530% (approximate, from memory), about the same as an MTB triple. You will end up having to choose between a super low gear or a high 100"+ gear, but I never use gears over 100" anyway.

[LollyKat]

Try Scheldon Brown's gear calculator, which covers the Rohloff and other hub gears.

I can't work out percentages but in inches (equivalent diameter of a penny farthing wheel!), your current set up goes from 17" to 104". A Rohloff with 40 chainring and 17 sprocket gives 17" to 90", i.e. you can keep your bottom gear and sacrifice a little speed at the top. You can always freewheel .

Rohloffs are very expensive but have won many converts.

[Si]

SRAM dual drive, et al. worth having if you don't need to?

I've used them on various bikes where there was an advantage (folders, 'bents) but they did feel a bit draggy to me.....would I have just been imagining that, or would a derailer at both ends set up be more efficient (assuming it was kept clean and lubed)?

[simonineaston]

19" to 95" is 400%. ie a quintupling of ratio.

While not wishing to hijack this interesting topic on alternatives to a triple crank derailleur set-up, my own favourite being the hybrid 3 speed hub/cassette option, but can you explain to me how the 2 gears (presumably "bottom" and "top") in the example above represent a change in ratio? And if they do, can you explain how the change in ratio equals a multiplying fourfold? I don't doubt you for a moment, I'd just like to understand what you're saying a bit better...
The only sum I can do with these two numbers that makes much sense to me is to express them as a fraction (and then multiply by 100 if I want to see the result as a percentage), thus: 95 over 19 = 5 - otherwise known as 500%. Flip the numbers over and divide 19 by 95 and I get .2 or 20% if multiplied by 100, neither of which sounds like the 4 x difference in ratio you are describing, Mick. [edit: although I see you actually write "400%" as well as "quintuple" - isn't quintuple the same as x 5?...
I think I remember my Maths teachers telling me a ratio is one number compared with another - if that's the case, then there must be some other number in addition to the 19 and the 95 that I don't yet know about! Do tell!

[beardy]

95" is 500% of 19" but the range is from 19" to 95" which is 76".
So the range is 76/19 or 400% of 19".

[simonineaston]

Thanks - interesting that you have explained the sum adequately without mention the word "ratio". Is it because the ratio is somehow implied by the sum "76 over 19"? I thought ratios looked like this: x:y...

[simonineaston]

Feeling slightly guilty that I grabbed the steering wheel and gave it a yank in the direction of ratio and ranges, I offer this observation as recompense: I quite like the hybrid-gear (SRAM's version is marketed as Dual Drive, as Brucey has already noted) over a triple crank for touring as it has a number of advantages for me. Using the example of Sturmey Archer's RF3 as the hub-of-choice, you can fine tune your gears by popping on any one of the 8 or 9 speed Shimano compatable cassettes. Plus you can readily change gear while stationary. Here's 2 examples, courtesy of the dear departed Sheldon.Either would suit me - I used a 40 tooth chainring here that would work on my Moulton, but of course you could just as easily use a bigger chainring for bigger wheels...

12-23 cassette, close ratios

11-32 cassette, wider ratios

[Mick F]

19" to 95" is 400%. ie a quintupling of ratio.

While not wishing to hijack this interesting topic on alternatives to a triple crank derailleur set-up, my own favourite being the hybrid 3 speed hub/cassette option, but can you explain to me how the 2 gears (presumably "bottom" and "top") in the example above represent a change in ratio? And if they do, can you explain how the change in ratio equals a multiplying fourfold? I don't doubt you for a moment, I'd just like to understand what you're saying a bit better...
The only sum I can do with these two numbers that makes much sense to me is to express them as a fraction (and then multiply by 100 if I want to see the result as a percentage), thus: 95 over 19 = 5 - otherwise known as 500%. Flip the numbers over and divide 19 by 95 and I get .2 or 20% if multiplied by 100, neither of which sounds like the 4 x difference in ratio you are describing, Mick. [edit: although I see you actually write "400%" as well as "quintuple" - isn't quintuple the same as x 5?...
I think I remember my Maths teachers telling me a ratio is one number compared with another - if that's the case, then there must be some other number in addition to the 19 and the 95 that I don't yet know about! Do tell!

My point is that if your boss gave you a 100% payrise, your pay would double. If he gave you a 50% payrise, your pay would go up by half of your original pay.

If he gave you a 200% payrise, your pay would triple.
400% is a quintupling.

95" is 500% of 19" but the range is from 19" to 95" which is 76".
So the range is 76/19 or 400% of 19".

Yep.
Increasing the ratio from 19" to 95" is quintupling the ratio.
19 + 400% = 95

[PH]

... and the week before?
Did you have 100% pay or 0%?
Your calculation means the Rohloff has 12 increases, which is correct but we all know it has 13 gears.

[Mick F]

The Rohloff has 14 gears but only 13 gear-changes.
Same idea as my 10sp cassette. The RH Ergo has 9 clicks.

Telegraph poles:
Ten poles hold up nine lengths of wire.