Can't decide on which multispeed hub for Dahon Speed Uno
 

I've seen an automatic 2 speed and one that is 'kick shifted'. The manual one seems like it would be fun/enjoyable. But would it get old, tiring, and annoying after the novelty wore off? I've never had a multispeed hub before.

My Speed Uno just seems kinda slow like I'm always topped out speed wise. I'm looking for higher cruising speed.

Any choice rim to lace it up too? Any spoke opinions?

Fun bike, lightweight, and convenient. I have other bikes; but they are never with me all the time. I keep this in my trunk for those opportunity rides.


In this video; it looks like he is topped out speed wise. That's how I always feel riding it. I need more speed!

You can try a smaller cog. Does the Speed Uno come with a 16T? You could try a 14T to start.

The Sun CR18 is a great rim to use, double wall with eyelets and comes with 36 holes so it will be a very strong wheel.

There was a similar thread a few days ago.
http://www.bikeforums.net/showthread...on-IGH-options

It's got a 17T.


Any link to the correct cog I need? Any special tool to swap it out? I've never worked on a coaster before.


edit:

I missed that link cause I didn't click on it not knowing what IGH stood for..(now I know!)

The Sram automatix seems to be the prefered hub. There are several threads concerning both. There is also the option of the 2 spped crank
http://www.utahtrikes.com/PRODINFO-F...0Crankset.html

http://www.bikeforums.net/showthread...sram+automatix

http://www.bikeforums.net/showthread...sram+automatix

Here is a link for a 15T cog. They are very inexpensive.
http://www.amazon.com/Sturmey-Archer...ster+brake+cog

They sell either 1/8" or 3/32" cogs. You can use either but the 1/8" is more durable. Plus you may have a 1/8" chain there already.

All you need is a small flat blade screw driver to swap the cog. There is a snap ring that holds the cog. There are some videos on youtube (the same as swap 3-sped IGH cogs).

Here is one of them:
http://www.youtube.com/watch?v=dxC-9NYrElo

Took it for a ride as is with my GPS. Comfortable cruising speed for me on this bike is 8mph all day long. Stepping it up to 10mph; not as pleasant pedaling experience. 12mph takes a lot more effort(faster pedaling more so then resistance). At 18mph I'm spinning the pedals. I can't break 20mph. Maybe I could with a stand up full on sprint; but I'm looking for constant cruising speed.

I wonder if this 15t cog would allow me to maintain 12mph as comfortably as 8mph is for me now?

I have about 1/2" of the dropout left. Will this 15t cog require me to remove links from the chain?

I'm not sure if you will need to shorten the chain, but you probably won't be able to use the FreeDrive chain cover. Biologic says you need a rear cog with at least 17 teeth for the FreeDrive.

-HANK RYAN-
Norman, Oklahoma USA

From 17T to 15T, it is like going from 8 MPH to 9 MPH so it won't be 12 MPH.

If there is 1/2" of dropout left, then 2 fewer teeth is just about right without taking out links.

After looking at the history of IGHs and reading posts here, I think one would have to really, really have issues with the shift cable to choose either the Sturmey-Archer Duomatic or SRAM Automatix two speed over a three or more speed IGH.

BTW, did you know that Shimano has a new three-speed (the SG-3R75) and a new five speed (the SG-5R35) in the works?

Amazing how life gets in the way.

I finally got it and got it installed. I need to go back to the original test spot to get more accurate comparison numbers. 9 mph is indeed what I get now instead of 8 mph. In regards to the 10 or 12 mph; I was seeing a lot of 14 mph. Also; I almost got to 22 mph. 21.8 mph. I think it's got more in it.

Also oddly; from the factory; it had a 3/32" cog on it and what appears to be a 1/8" chain. Did they go with the 3/32" because it was either cheaper, lighter, available, or they just didn't care? I think all of the above.

Also, when I undid the back axle; the chainstays spread apart about 1/4".

Factory cog and axle placement:

http://s12.postimg.org/4fi5jxxmh/20130815_110549.jpg

3/32" chain spacing:

http://s24.postimg.org/xwks0vsnl/20130815_134522.jpg http://s21.postimg.org/qar5lg2bn/20130815_134555.jpg

New cog spacing:

http://s24.postimg.org/yg3nfdo7l/20130815_142226.jpg

1/8"? chain and 1/8" cog:


http://s24.postimg.org/xf3eq9781/20130815_142329.jpg


I think something with either the grease or ******er spring are acting up.

http://s24.postimg.org/b4fjqa9xt/20130815_143510.jpg

looking sheldon's gear inch calculator you went from 64 gear inches to 72 which is a good ideal range for single speed bikes. I did the exact same thing to my Tern dropping out the 17t cog to 15t and gained around the same but changing out my tires from the citizens to a pair of kojaks. Oh boy do those babies roll fast!

at least with this new setup you can take your time and decide on whether you really need a two speed hub. The ONLY choice you really have is the sram automatix or if you can find some old torpedo hub from another vintage bike. The sturmey archer s2c mostly have problems for alot of users and some of them just locked up the wheel after the insides when kaput in short distances! If automatix isn't your thing then a 3 speed hub would be more durable from any of the big manufacturers (sram, shimano, sturmey)

NuVinci 360?

I am using 47T front, 13T rear on my Mu, perfect transmission ratio for Berlin!
Don't need gears, and gear hubs are to heavy, not worth the hassle, jm2c.

Flatlanders have simpler needs.

I wonder if I have enough room left in the drop out to sample a 13t cog?

smallest i've seen from sheldon's site for a sturmey archer cog is 14t

Shimano nexus cogs don't even go below 16t when I tried looking.

I found it on Amazon:

http://www.amazon.com/Sturmey-Archer...dp/B003RLJZO6/

I checked the gear inch calculator:

[TABLE]
[TR]
[TD][/TD]
[TH="bgcolor: yellow"]58[/TH]
[/TR]
[TR]
[TH="bgcolor: yellow"]17[/TH]
[TH="bgcolor: white"]63.7[/TH]
[/TR]
[TR]
[TD="align: center"]13.3 %[/TD]
[/TR]
[TR]
[TH="bgcolor: yellow"]15[/TH]
[TH="bgcolor: white"]72.2[/TH]
[/TR]
[TR]
[TD="align: center"]7.1 %[/TD]
[/TR]
[TR]
[TH="bgcolor: yellow"]14[/TH]
[TH="bgcolor: white"]77.4[/TH]
[/TR]
[TR]
[TD="align: center"]7.7 %[/TD]
[/TR]
[TR]
[TH="bgcolor: yellow"]13[/TH]
[TH="bgcolor: white"]83.3[/TH]
[/TR]
[/TABLE]

starting from your 17T even with the 15T it's going to be the sweet spot for single speeds with minor hills and such. 14T is starting to push it in the 77GI's. But at 13T you are pretty much going to have a hard time to pedal anything but flat and slight declines, 83-84 gear inches isn't something you do on a hill climb. going from 17 to a 13 is quite a huge jump and I would be best if you try 2-3 teeth max.

Spinning out on a downhill you can always coast for all that matters, but having too high of a gear on a loong uphill and you are walking up the hill at 1/4 of the speed if at that since you'll be pushing the bike up too! :)

Brompton 6spds have SA hubs with 13 and 16t,so they're def available.

13~15, but the 2 speed is 12~16 , si You cam buy and change them, if it suits...

Mine is 13/16.

http://www.velovision.com/showStory.php?storynum=946