Folding Bikes - Newby Needs Advice On Conversion of Dahon Mu Uno To IGH

Hi to the Folder Posters here. Need some simple advice; am planning on acquiring a Dahon Mu Uno which is a single speed to replace my recently stolen Boardwalk. IS it much of a job to convert this SS setup to a 3 speed or 7 or 8 speed in the future should I decide to? How much weight approx would this add to the Mu Uno? Chances are may just decide to keep it a single speed but am exploring the options should I decide to go that route(conversion) on down the road in time. Thanks for any advice.

You will need 135mm between the dropouts to fit IGH. It will probably already have horizontal dropouts, so that's good you won't need a chain tensioner. You will need a new rim and spokes and the skill to lace up a wheel or pay someone else to do it (about $40.00 US). The hub, parts kit, and shifter, sprocket, may or may not need new chainring.
Since you haven't purchased the Uno yet, it will probably be cheaper find a model that comes equipped with the IGH. I think Downtube has a model that is fairly reasonable.

I thought the dropout spacing made it impossible except for the automatic 2 speed mod that's been posted on these forums.

I thought the dropout spacing made it impossible except for the automatic 2 speed mod that's been posted on these forums.

Uno rear spacing is 120mm .. so any of the hubs that have an OLD of around that dimension could be used ( some Sturmeys are good choices.. a Sturmey 5 wide range could be ideal with 119mm OLD and a hub brake option).. my vintage Sachs Automatic is at 110mm, so not a lot of wiggle room with the relatively short axle, but it is working flawlessly on the Uno..

Lots of hubs will fit into 120mm. Heck, the Sturmey Archer 8 speed (XRF8) hub to fit into 110 mm OLD on a my vintage Moulton MK3. You'll have no problems finding a nice one to fit.

It'll cost you about $150-$200 in parts alone for new ones, though. Hope you know how to build your own wheel.

Guys--Thanks for the Replies so far. This is exactly the Info I'm looking for.

What IGH do you feel is the best value for the money spent?


Approx how much weight overall do you think this Mod would add to the Bike? Thx

Out of the choices you can use with the Mu Uno, i'd personally go with the 8 speed Sturmey Archer X-RF8 (w). I would not recommend purchasing an 8 speed Sturmey Archer that is not designated with the (w), they are an older design which was much more prone to failure, whereas the new hubs are of superior reliability in comparison.

Personally though, I would also consider an REI Novara FlyBy, since the FlyBy already has an 8 speed internal gear hub, and has been dropped in price to $590. The only thing the Mu Uno has on the FlyBy at that price is that the Mu Uno has a sweet black paint job, and the FlyBy looks like a good candidate for an ugly paint job award.

G

Approx how much weight overall do you think this Mod would add to the Bike? Thx

It depends on the hub you choose. The Sturmey Archer 8 speed hub weighs 1790grams.

Technically what's changed with the 'w' sturney archer hubs? I've just seen there's an updated version of the 5 speed hub I have.

Also, the 'S' low-flange hubs are much lighter than the 'X' high flange. With the RF-5 there's 200 grams difference, which makes me wonder why my Dahon uses the high flange version. Or is there some other difference between the 2 models that makes the x-rf5 more suitable?

It depends on the hub you choose. The Sturmey Archer 8 speed hub weighs 1790grams.

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SesameCrunch--Thanks, that SA 8 speed hub alone adds close to 4 pounds to the Bike. As I wrote, this is an option I can look at, this conversion. Living in Miami, its pretty flat except for the Elevated Intercoastal Waterway Bridges, which I rarely cross. When I crossed them in the past on my Dahon fixed speed Boardwalk, I was able do remain seated so really no problem here with a single speed. One thing that really caught my eye with the Mu Uno is the Lite weight factor which I would definately appreciate as I use public transit often. Many times I lift up and load the Bike on Bus carriers, carry or muscle the bike up Escalators to get onto Metro Trains ect. The Boardwalk got to be a handful doing it several times a day, this loading/unloading of the Bike for Public Transit. One wouldn't think an extra 5 pounds or so makes much of a difference but for the awkward height that the Bike Carriers are located at on our City Buses, its did make quite a difference.

Abneycat-Thanks. One of the reasons I looked at the Uno is that the Catalog Company I am dealing with and from who I would be obtaining the Mu Uno from is making an exception for me and doing a One-Time Special Order for me. A Special Order from Dahon California Actually. The Mu Uno was of one the Bikes in the price Range I could get with my 8 years of accumulated Gift Certificates. Another choice from them is a is a Red Dahon Speed P8 which I had considered also. If I could use the Gift Certificates anyplace, the REI Flyby would be a contender for sure. Nice Bike, lousy paintjob. I attempted to sell and or barter the Gift Certificates Online during the Xmas Shopping season but no luck. I wasn't willing to discount them over 40% to unload them so this Special order Dahon was the closest thing for me being able to cash in the Certificates and still end up with something I could use without taking much of a Bath financially.

Check out the three and four speed hubs also.

Do you need special IHG for small wheels or do you need to adjust the chainring/cog size for small wheels?
If you need to keep it light, a 3-speed is probably the best bet. You will have a gear for up-bridge, down-bridge and flat.

here is one that I found online and it weighs about two pounds. http://www.ebikestop.com/sturmey_archer_s30_s_rc3_3_speed_coaster_brake_hub-HU2210.php,you just have to get a 20" rim and get it built. I would think that adjusting the cog and chain ring per the Harris site will do it.

Could get the Shimano instead http://www.universalcycles.com/shopping/product_details.php?id=10675

DynocoasterMichaelW--Thanks for The Info. I'll look into them.

@miamimike: I upgraded my Boardwalk S with a Shimano 3 speed with coaster brake, as referred to by Dynocoaster. Works fine.

Thx GP--sounds like a good plan should the Single Speed be lacking.

Thx GP--sounds like a good plan should the Single Speed be lacking.

If you're into maintaining the natural aesthetics of the bike, I would also consider going 2 speed (no cables to the back or shifters to be found)... Here's SesameCrunch's Sachs kickback 2 speed Moulton.

http://farm3.static.flickr.com/2680/4365538116_0a55aeabb2.jpg

And my Sachs Automatic 2 speed Mu Uno .. gearing on mine is 54" low and 74" high and covers either side of the of stock 62" Dahon Uno.. in practice, it has been perfect for riding in moderately hilly Marin county.

http://farm3.static.flickr.com/2522/3993619833_3e86ef2998.jpg


Although the Sachs hubs can be found (some NOS), they have been out of production for better than 30 years, however, one more hub to consider is the new, to be released soon, Sturmey 2 speed kick back hub as used on the new Pashley Moulton TSR-2

http://farm3.static.flickr.com/2692/4365573444_7204be206d_o.jpg

BruceMetras--Thanks for the info on the 2 Spd, its an interesting concept. How much weight overall does this add to the Uno? Nice pics, esp of the Uno. Can't wait til I get mine, looking at yours.

Great Pics, Nice looking Bikes!

BruceMetras--Thanks for the info on the 2 Spd, its an interesting concept. How much weight overall does this add to the Uno? Nice pics, esp of the Uno. Can't wait til I get mine, looking at yours.

Great Pics, Nice looking Bikes!

Not much added weight, you'd be replacing a not particularly light coaster brake Shimano single speed hub with whatever coaster brake 2 speed hub you choose.. I would guess that the new Sturmey kickback will be the lightest of them, but I haven't seen one yet... by the time you're done, maybe a pound difference... if that..

A 2 speed may not be the answer for you either, but if you haven't read the thread about mine, HERE IT IS! (http://www.bikeforums.net/showthread.php?592559-My-Dahon-Mu-Duo-a-blend-of-old-an-new&highlight=mu+duo)

my two favorite IGHs are the Sturmey Archer AW 3-spd and the Shimano Nexus 7-spd

Not much added weight, you'd be replacing a not particularly light coaster brake Shimano single speed hub with whatever coaster brake 2 speed hub you choose.. I would guess that the new Sturmey kickback will be the lightest of them, but I haven't seen one yet... by the time you're done, maybe a pound difference... if that..

A 2 speed may not be the answer for you either, but if you haven't read the thread about mine, HERE IT IS! (http://www.bikeforums.net/showthread.php?592559-My-Dahon-Mu-Duo-a-blend-of-old-an-new&highlight=mu+duo)

Bruce, again, Thx for the detailed info & Photos. While a Single speed is OK here in Miami(in fact many here are converting their 26 " bikes to a fixed single speed) I won't always be here where its flat. In visiting my hometown in NW Penna, the city has some pretty steep long and short hills. Some hills are a short steep with a 25-35% grade though most are smaller, but longer. I haven't layed a protractor on these hills so my Grade comments may be a bit off. How does your 2 spd conversion do in your Area like around San Francisco? Anything that works in SF would be more then OK for my area. Nice clean looking conversion you did there on your Uno~

How much overall in cost(parts) do your figure your Conversion cost? Thanks