Showing posts with label Automatix. Show all posts
Showing posts with label Automatix. Show all posts

Wednesday, October 5, 2011

SRAM Automatix (A2) vs. Sturmey Archer S2C


I'm in trouble. I've been thinking about my "next" winter bike. That is bad news, because I have neither the time nor the spare cash right now. Then again, I'm only thinking... thinking is free, right?

One of the most common problems with riding in a combination of salty slushy muck and sub-zero temps is that brake and shifter cables sometimes don't want to work properly. Careful attention to lubing them and "sealing" them from the elements helps, but careful attention isn't exactly my style. I have also been thinking about trying skinny rather than fat studded tires this time, but that's not what this post is about. Another post, perhaps.

With winter bikes, less is often more. There are two internally geared hubs on the market I am interested in (see title). Both offer two speeds and a coaster brake and both would eliminate the 2 cables normally running to the rear of the bike. In addition, a coaster brake will never be affected by wet/icy/slippery rims or brake rotors. For these reasons I am excited to build a winter bike that uses one of these hubs.








The SRAM Automatix (A2) shifts automatically. The S2C features a "kick shift", meaning that a little back-pedal will switch it between it's two gears and a harder back-pedal will engage the coaster brake. Gearing is very similar, with the S2C offering 100% (direct drive) and 138%, while the SRAM Automatix (A2) offers 1:1 and 1:1.37 gearing. The SRAM site shows a "bandwidth" spec of 124% while the Sturmey site lists an "overall range" of 138%. I must confess I'm a little confused... shouldn't the "bandwidth" of the SRAM be 137%? I'm hoping somebody smart will read this, comment and sort me out.

Another consideration is that the OLD (over locknut dimension) on the S2C is 116mm (although the axle is long enough to space it out far enough for 130mm rear spacings) while the SRAM OLD is 130mm. I tend to favour the 130 for potential frame (as in a bike I already own) reasons.

I almost wish one of the hubs was significantly less expensive than the other, but they both appear to retail for 60-80 bucks US, which is awesome in my opinion, considering what more elaborate internally geared hubs sell for. I'm further torn by the manual vs. automatic issue... if the auto works well, it is one less distraction while I'm riding in conditions demanding my full attention. On the other hand, I'm not sure I want to give up control of when the bike shifts! Arg!

So, what on earth am I gonna do? I've read some bikeforums stuff, but as usual there are arguments for both and they're most often about Bromptons and bikes like that. Can you, dear reader, offer me any insight? (Cafiend, any thoughts?) If so, please comment. Can you instead offer weird, incomprehensible ramblings? You should comment too, but I warn you that I might actually get you.



Note, July 24, 2012: When I wrote this post, I had no experience with either hub and still don't. However, there is a bunch of useful experience / performance info in the comments now. If you're considering a purchase, I strongly encourage you to read the comments on this post.


Yer Conflicted Pal,
R A N T W I C K