Utility Cycling - Sram i-motion 9 on a cargobike

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LucianTheOne
02-28-12, 10:43 AM
I wanna build a cargo bike, Xtracycle type, with a Sram i-motion 9 hub.
Does anybody have such a configuration? Someone write on a forum that this hub does't work with a long shifting cable.
Is it true?

badmother
02-28-12, 02:06 PM
Try the Yahoo IGH group http://groups.yahoo.com/group/Geared_hub_bikes/?yguid=374120424

I do not know the hub, but how can a long cable be a problem? A long cowered cable (innside a housing) could be a problem, can you run it partly uncowered? This could of course give you ghostshifting if there is flex in the frame, I had the problem with the Nexus7 on my Dogbike2.

I was thinking about using high quality (the braided extra stiff type) BRAKING housing to solve the problem since the stiff housing would not be as compressed when shifting as the cheaper stuff and also it has more room innside (made for a thicker brake cable) there would be less friction.

Also if you add one or two of these http://www.sjscycles.co.uk/ravx-luber-x-adjuster-kit-prod23361/ you can keep it properly lubed with little extra work.
Just thinking, did not try it yet, parts are in the mail.
fietsbob
02-29-12, 03:12 PM
Bad things on the horizon to cause your cables to cower in fear..

fietsbob
02-29-12, 03:29 PM
since you are the builder , so able to think 'fabricate' rather than just shopping,
using the particular tube that is automobile hydraulic brake lines use
would not be compressed, lengthways , and in all the portions of your cable run that does not have to flex
that serves well as housing over the cable, between stops you put on the frame to receive
the housing that is needing to flex, there the shifter housing a bundle of lengthways wires
also compression resistant can go there ..

Of course Rohloff resolves much by their pull/pull cable system, and having the gear sequencing in the hub.

single cable shifting is pulling against a return spring.. sluggish returns can
be overcome with a beefier return spring,,

I did a couple booster springs on my Sturmey Drum brake hubs ,
adding a return force that overcame housing interior cable drag..