Drive Chain Advances

Andy88

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Ive seen a few pedal and electric bikes with carbon fibre drive belts and solid driveshafts as opposed to traditional steel chains.

Are these innovations the way of the future for IGH? I can't see how they would work with derailleurs.



 

anotherkiwi

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Both require special frames. Shaft drive is les efficient and heavy.
 

Nealh

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The CF belt drive also known as a Gates belt drive is being seen a bit more on bikes generally commuter or leisure bikes. These are aligned with a IGH drive or a fixie and like the chain driven models there are options for belt tensioning.
Normal chain bikes can be converted to IGH though still require a derailleur type tensioner.
  • Derailleur type tensioner looks a bodge to me but probably easiest way for chain/belt wheel removal.
  • Eccentric Bottom bracket which may well rule out a crank drive conversion. Also has an enlarged special bottom bracket shell that is fitted with a std size BB with ext bearings.
  • Horizontal drop out which appears simple as the wheel nuts are undone and slid forwards to slacken the chain or belt.
Belt drive though as has been said will be expensive esp if you want to change the gearing with the belt drive wheel.
 

anotherkiwi

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Derailleur type tensioner looks a bodge to me but probably easiest way for chain/belt wheel removal.
Also prevents use of fully enclosed Chainglider chain protection.

A chain enclosed in the aforementioned Chainglider in a frame with horizontal dropouts has all the advantages of a belt drive without the inconveniences.

My choice would be a normal frame with an Alfine chain tensioner and the open Chainglider, but I'm a cheapskate...
 

Nealh

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With IGH's you have to decide between front hub or cd. A cd will cover most aspects of riding even hills (10%) but with hub you will need to select one with an rpm that suits your needs.
A 20t sprocket for instance combined with the nexus or alfine 8 will give you a gearing of 38,31,27,24,20,16,14,12 in a cassette, as can be seen not very even leaps in gearing.
Shimano recommend 1.9.1 gearing ratio but have read other forums where user have gone above.
Recommended chain wheels and sprocket for close to 1.9.1 ratio I believe are 36/16, 38/18, 40/19, 42/20 & 46/22. 46/20 gives a higher 2.1.1 ratio.
 
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Andy88

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With IGH's you have to decide between front hub or cd. A cd will cover most aspects of riding even hills (10%) but with hub you will need to select one with an rpm that suits your needs.
A 20t sprocket for instance combined with the nexus or alfine 8 will give you a gearing of 38,31,27,24,20,16,14,12 in a cassette, as can be seen not very even leaps in gearing.
Shimano recommend 1.9.1 gearing ratio but have read other forums where user have gone above.
Recommended chain wheels and sprocket for close to 1.9.1 ratio I believe are 36/16, 38/18, 42-44/20 & 46/22.
46/20 gives a higher 2.1.1 ratio.
You are a star sir
 

Nealh

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I have been looking at hybrids with Alfine 8 for a conversion with a bbs01, Ridgeback flight04 looks very nice but has eccentric bb. A closer look at the bb suggests a bbs will fit with the positioning of the ebb as it sits.
The other option is to try and convert my ht mtb with one to try as a off roader as mtb forums suggest they work quite well and seem to cope with up to 750w of power.
 
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Andy88

Esteemed Pedelecer
Nov 6, 2016
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I have been looking at hybrids with Alfine 8 for a conversion with a bbs01, Ridgeback flight04 looks very nice but has eccentric bb. A closer look at the bb suggests a bbs will fit with the positioning of the ebb as it sits.
The other option is to try and convert my ht mtb with one to try as a off roader as mtb forums suggest they work quite well and seem to cope with up to 750w of power.
It might be your best bet to test with your own bike first, its an absolute minefield out there in terms of market availability.

The more powerful the motor the less gears we need so i read. Take a look at this if you haven't seen it already.

https://www.electricbike.com/mid-drive-kit-igh/
 

Rohloffboy

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Sep 1, 2015
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Had a test ride on a Shaft Drive Hard Tail at Harrogate back in 1999.

It worked fine, but I just thought it was adding more complications compared to the simplicity of a chain.

Likewise Gates Belt Drives, requires the bike frame to split at the chainstay.

I run the Rohloff SLT-99 chain 8 speed with my Rohloff igh, no fancy quick link on my chain, the joint is riveted at the joint, which I do myself with the Rohloff Revolver chain tool.

Some things just do not need changing, and the chain is one of them.