# SRAM I-Motion or Shimano Nexus / Alfine



## neal_b (Apr 4, 2007)

Is there a source in the US for either of these groups.

Looking to build a commuter bike w/ internal gear and dynamo hubs.

Thanks


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## shiggy (Dec 19, 1998)

neal_b said:


> Is there a source in the US for either of these groups.
> 
> Looking to build a commuter bike w/ internal gear and dynamo hubs.
> 
> Thanks


Your LBS can get either from QBP. The I-Motion is about twice the cost and weight of the Nexus.


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## itsdoable (Jan 6, 2004)

Harris Cycles has both in stock when I asked recently.

They don't have any ride time on the iMotion yet, so no experiences. But they said the iMotion has to be _*very*_ good to compare well with the Alfine.


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## neal_b (Apr 4, 2007)

Great, thank you.

Anybody know anything about the SRAM Sparc electric hub? I've been looking at converting an electric scooter motor but this looks pretty intriguing.


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## kapalama (Dec 8, 2006)

Anyone see any English Langauge reviews of this anywhere? I have seen the German reviews, but I don't speak it.


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## UN-COG-KNEE-TOE (Mar 7, 2008)

*SRAM i-Motion 9*

anyone have any information on WHERE to BUY an I-Motion 9 Hub NOW?, i have searched, no one has one nor has any anticipation of getting one anytime soon, a US or EURO Purchase is fine...... ideas? THANKS!


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## itsdoable (Jan 6, 2004)

kapalama said:


> Anyone see any English Langauge reviews of this anywhere? I have seen the German reviews, but I don't speak it.


The best review I've read on them is here: http://www.velovision.com/mag/issue29/vv29hubgears.pdf

http://hubstripping.wordpress.com/ is a good website for geared hubs.



UN-COG-KNEE-TOE said:


> anyone have any information on WHERE to BUY an I-Motion 9 Hub NOW?


An lbs has the coaster brake version i-drive in stock, but I'm assuming you want the disc brake version since Harris Cyclery has a coaster.


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## VTECnical (Jul 19, 2008)

Good info. Thank you.

Here is a link to Harris...

http://www.sheldonbrown.com/harris/hubs-internal.html

I think I am going with the Nexus 7 speed with coaster brake for the girlfriend's new bike...


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## UN-COG-KNEE-TOE (Mar 7, 2008)

*Sram I-motion 9 Hub*



itsdoable said:


> The best review I've read on them is here: http://www.velovision.com/mag/issue29/vv29hubgears.pdf
> 
> http://hubstripping.wordpress.com/ is a good website for geared hubs.
> 
> An lbs has the coaster brake version i-drive in stock, but I'm assuming you want the disc brake version since Harris Cyclery has a coaster.


.....YES - i am choosing the SRAM as i NEED a DISC Hub because of the Frame i have. ..anyone selling one or KNOW where to Get one in a reasonable amount of time?


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## pursuiter (May 28, 2008)

I bought this one from Harris last month, must have been one of their last. Just got it up a running today. Still need to built the Dynamo wheel and LED light system. A little iM9 porn:


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## UN-COG-KNEE-TOE (Mar 7, 2008)

*Sram Hub*



pursuiter said:


> I bought this one from Harris last month, must have been one of their last. Just got it up a running today. Still need to built the Dynamo wheel and LED light system. A little iM9 porn:


THANKS - NICE POSTING - and GREAT Pics, Nice build up too... can you please post another shot or 2 showing the Downtube and Chain stay Cabling, i would like to see how you handed the Shift Cable routing on your FRAME ...Harris Cyclery is OUT of Stock on those DISC Hubs NOW... wish i moved sooner!


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## pursuiter (May 28, 2008)

Thanks for the kind words, it's been fun making my ultimate commuter. Still have the head lamp project and the enclosed chain guard to go 



UN-COG-KNEE-TOE said:


> ...i would like to see how you handed the Shift Cable routing on your FRAME...


I would, but right now it's plain nasty. The pre-made cable is 12" too long and it looks stooopid. I need to figure out how to shorten it....


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## UN-COG-KNEE-TOE (Mar 7, 2008)

*SRAM i-Motion 9*



pursuiter said:


> Thanks for the kind words, it's been fun making my ultimate commuter. Still have the head lamp project and the enclosed chain guard to go
> 
> I would, but right now it's plain nasty. The pre-made cable is 12" too long and it looks stooopid. I need to figure out how to shorten it....


Thanks .....I understand - so Your Frame has NO DISC Tab, which Brake are you going to Run in the REAR?


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## pursuiter (May 28, 2008)

UN-COG-KNEE-TOE said:


> ...which Brake are you going to Run in the REAR?


I'm running an Avid 7 v-brake so I can mount a rear rack (Surley).


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## VTECnical (Jul 19, 2008)

Nice bike! Let us know how the 9 speed works!


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## Speedub.Nate (Dec 31, 2003)

I recently built an i9 into a 20" wheel and have had a few rides on it.

Yes, as reported, the hub is a beast. Fair warning of weight bothers you.

On the other hand, this is perhaps the smoothest running, quietest gear hub I can remember pedaling. I've got an older Nexus 7 and Sram Spectro 7 to compare it to, and of course the Speedhubs. I spent a short amount of time on a NuVinci CVT two years ago at Sea Otter, and recall those hubs being similarly smooth and quiet.

Shifts on the i9 are quick and silent, and the shifts drop under load. Compare this to Sram's Spectro, which allows the shifter to be twisted with no extra resistance, but won't initiate a downshift until pedal pressure is let up.

My main complaint of the hub is the internal spring that tensions the shift cable makes the indexed twist shifter very sensitive. Rather than "light and crisp" shifting action, it's just "light," and I end up overshifting often. I'm sure it's just a matter of me and the hub becoming better acquainted, but I do wish other gear hub makers would adopt Rohloff's example of indexing the hub internally, leaving the shifter "stupid" and uncomplicated.

I loaned this bike to a friend to ride with us yesterday to the Tour de Fat. She's Dutch and grew up with bikes, and admitted that despite gear hubs being littered across her home city, they have a reputation for poor performance and non-serious cyclists (she's wouldn't call herself a "serious cyclist" despite riding daily — she bike commutes because it's what you do). She was totally amazed by this hub! Pedaling or coasting, I couldn't even hear it as she rode next to me, unlike other gear hubs and derailleurs we rode near. She agrees that the shifting is smooth and nearly unnoticable, though we weren't tackling any big hills during the ride.

I'm happy to hear Harris is selling these. I read recently that Sram decided there is no market for the i9 in the US, and had no plans to sell them here, with the exception of a handful that might come equipped on a limited-production Bianchi model that would only be available in "company stores" (???). If any of that is true, Sram is missing out. It's clear to me that a hub this good installed on lower-priced cruiser and commuter bikes could turn many potential buyers into gear hub converts.


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## pursuiter (May 28, 2008)

Nate, great post. I've only got ~10 miles on it, I am loving it.

Question: do you know how to shorten the cable?


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## Speedub.Nate (Dec 31, 2003)

pursuiter said:


> Nate, great post. I've only got ~10 miles on it, I am loving it.
> 
> Question: do you know how to shorten the cable?


Yeah, there is a PDF on Sram's website. It's pretty straight forward, but does require the precise measurement of cable.

https://www.sram.com/en/service/sram/pdf/2008/TM_GHS_MY08_E_RevA.pdf

Check out PDF pages 23-24.

The cable change port is hidden in the grip portion of the shifter, shown in figure 6.

Make sure to put on the oversized plastic cap before measuring and cutting the cable. If you measure from the ferrule, you'll cut it too short.

Final adjustments are done from Gear 6.

Here is the process, Reader's Digest version:


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## pursuiter (May 28, 2008)

Thanks, that's just what I needed :thumbsup:


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## frankenbiker (May 23, 2004)

Ok but can it take e-motors or tandem use?


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## pursuiter (May 28, 2008)

The Alfine might, the IM9 isn't worth trying, it's not really up to any aggressive use.


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## randonneur (Sep 25, 2007)

*Im9*

Pursuiter, do you have evidence to back up your claim?



pursuiter said:


> The Alfine might, the IM9 isn't worth trying, it's not really up to any aggressive use.


I have heard no claims that either the Alfine or the iMotion hubs are anywhere near as fragile as older inferior hubs. The Speedhub is rated for 100 Nm of torque, and I can attest it is bombproof in all conditions. The NuVinci is claimed to handle 130.

Nice to see so many good choices finally.


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