Re: Nexus cable pull and shifter options.

Do any of the Shimano Nexus experts out there see any problem with this?
Would it harm the hub in any way?

I really like this idea and would love to give it a shot.

Thanks for sharing Bret.

-Bruce-

Bret Wade said:

Quoted message said:

I just found a Shimano Nexus 7-speed hub at the Trexlertown swap meet.
The shifter is not part of the deal, though.

Standard shifter is either a twist-grip or a rapid-fire type. Is
there any chance that an STI shifter would pull the right amount of
cable? > How much pull is needed per shift, anyway?

Quoted message said:

I'm following up on an old thread, not to continue the discussion but
for the benefit of anyone googling for a solution to the question of
whether it's possible to adapt a Shimano 9sp shifter to a Nexus 7sp
internal gear hub. It is.

I measured the cable pull of the two systems and found that the ratio of
the Nexus/9sp systems was slightly greater than 2:1 (Unfortunately, I've
lost track of the measurements so I can only describe them from memory
in general terms). I had a spare Travel Agent brake cable adapter on
hand and measured the circumference of the two diameters and found that
the ratio was slightly less that 2:1. Doing the math I found that
running a SH 9sp shift cable through a Travel Agent would come very
close to a producing a Nexus cable pull.

I was idly wondering whether something like this could be made to work. I
presume that it would also work with STI. Now all I need is the travel
agent, and a 9-speed STI shifter. I don't suppose the 8-speed I have
sitting around would work.

Thanks for the information.

Ah, one note: it does work "backwards" from the way you'd be used to, in
that pulling on the cable puts you in a higher, not lower, gear.

Quoted message said:

I've built a bike with this setup and it works very well. I used a 9sp
barend shifter with a travel agent and an inline barrel adjuster. I was
prepared to modify the Travel Agent ratio with a layer of masking tape
and/or filing, but found it wasn't necessary. Here's a picture of the
resulting bike:
http://www.fischer-wade.homelinux.org/bici/

You can find the Travel Agent here:
http://www.excelsports.com/new.asp?page=8&description=Travel+Agent+%2Dea%2E+with+adjuster&vendorCode=PS&major=6&minor=8

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David L. Johnson

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