zboud

Hello,

I'm thinking of upgrading my 2010 Mu Uno with a belt drive. Given the specs from Gates, if I want to get a similar ratio to what I have now (56/16), I would need the 70 t chainring and 22 t cog. The chainring is around 245 mm in diameter, and the cog, 79 mm.

As I am currently away, I cannot measure the frame myself, but I'd like to order the parts for when I get home...so I need your help!

Two questions then:
-I am afraid using those rings will lead to the belt rubbing on the frame. What is the clearance between the chain and the frame on a stock bike? What is the maximum size of chainring the frame can take?
-What is the "chainstay" length on the Mu Uno? It conditions the number of teeth of the belt...

Thanks a lot for your help.

Mu_who

Please keep us updated with ur info...i have a mu uno as well..i want to go belt drive and sram auto 2speed.

CHECHO

I did that upgrade to my mu uno one year ago... I had the same concern you have... I contacted gates ditectly and they helped me to choose the right configuration.. Here's what they answered:

"It looks like your current ratio is a 2.9/1. The closest we could get with Carbon Drive is a 60x22x113 which will give you a 2.7/1 ratio. You would lose some top end but gain a little climbing ability."

BTW I also installed the sram automatix 2... I highly recommend it!

mct1709

thread ressurection :-) have you actually done the conversion ?

any chance to post exact part numbers?

mct1709

hiya could you or someone who went with the conversion post me the exact part numbers from gates?

sweeks

I seem to remember that Thor did a belt conversion on a Mu a few years ago. The Mu frame doesn't have chainstays as such, so it's possible to to this. A regular frame would have to have modifications to the drive-side chainstay for the belt to be installed.
Steve

Mu_who

Hey guys fyi thor also sells the sram automatic 2 speed hub with the rim attached. All u need to do is swap the inner tube and tire.

I wanted to do the belt drive conversion as well, but never got around to it.

zboud

Yeah, I did convert my Mu Uno.

I used a 55 teeth belt ring, a 111t belt and a 22t cog. I use a backwheel with a Sturmey Archer S2C hub so the gears are not too small.

First try was using a 70t belt ring and a 120t belt...it was rubbing on the frame. It's now for sale if anyone is interested...

mct1709

are you perfectly happy with 55*22*111t setup?

mct1709

can you recommend highly enough 60*22*113?

I would perhaps hold off on sram automatix 2 until i get belt conversion first and see how it goes

mct1709

hi, can you post me pm or post link here to thor website that sells sram automatic 2 speed hub with the rim?

which country you refer to? btw Im in Ireland.

CHECHO

Yes, I highly recommended. It has been a couple of years since I did the upgrade and it has been really great.

CHECHO

Hi, SRAM just discontinued the Automatix, however you can find still some units in Amazon or eBay.

Mu_who

Sorry i cant post links.

Just google

thorusa (DOT) com

look under accessories

its listed for
Company is in usa.

Free Wheel with 2 speed is listed for 199.99 us currency

mct1709

found link to us site with the full wheel. thx

my mu uno will arrive next week from uk

gates europe replied to my email and are now looking for the teeth count.

lets say i upgrade my single speed to gates belt, would the very same belt and accessories fit sram automatix if i decide to get sram at a later time?

BruceMetras

Yes, the Automatix hub will accept the same Gates cog.. I ran an Automatix 7 or 8 years ago to my own Mu.. also went with 451 wheels.. really enjoyed that bike until someone else just had to have it.. I started with chain drive and eventually went to belt on 406 wheels .. also ran the Automatix on a belt drive Moulton TSR

My 2 speed Mu Uno

leoho5

Hello Bruce,

Looking at the link you posted, I noticed you laced a 36h hub (Automatix) onto a 24h rim by skipping every 3rd hole. May I ask how you calculated the spoke lengths as the 24 holes are not evenly spaced. Did you just add a few mm's to the regular 24 hole calculated spoke lengths? Or did you somehow calculate the spoke lengths exactly?

Thanks!

BruceMetras

Sorry, not sure what I did that long ago.. I'll see if I saved any of my calculations in a file..

leoho5

Thanks and no worries. I'm assuming that the offset spoke lengths would only be a few mm's longer than the regular lengths.

L Arnold

A few details on Belts.

I've got available some new Mu Uno's built with belts by Dahon.

Interesting other bikes to do belt conversions to would be

Mu N360
Vitesse I7
Vitesse I3

The Vitesse I3 is a very cool bike for the money. $500. SRAM I3 w/ Coaster brake.

You can see some of these on my site nomadic (dot) net

I will get the math done for various conversions in the coming days.

BruceMetras

The Vitesse chainstay or seatstay would need a break in them for belt use (to be able to install and remove a belt).. the Mu frames are good candidates because they don't have a conventional chainstay..

mct1709

Thank Bruce.

What is kind of depressing to see someone shared similar experience to mine. My first mu uno was taken in 2014 when someone else took it. Since i loved my first mu uno so much i decided to source another one online and came across same color on UK ebay (it's coming in matte black).

Now am still in process of sourcing some neat fenders, since here in Ireland rains quite a bit so this would be first upgrade before sram automatix 2 even gets ordered

BruceMetras

Your's is the sad story .. not mine.. I should have added some $$$ signs .. I was offered a cash deal I couldn't pass up for mine.. fingers crossed, I've never had a bicycle pinched from me, however, I did have a nearly new 1977 non-electric start Triumph Bonneville stolen .. it was recovered almost 10 years later as a rusted shell, I never retrieved it, too sad.

Have fun with the Mu Uno, terrific bike!

L Arnold

Good Point Bruce. I did know that but... now I'm onto another tack.

I am going to test a Patterson 2 Speed into one of these bikes first (keep the chain for starts). I do have a Gates adapter for the patterson but next will be getting a small enough cog in the back to match the Patterson (28x46 effective)

N360 Belt + Patterson would make a capable Cargo/Touring bike it seems. Vitesse I7 also (not braking the frame just yet).

mct1709

Thanks Bruce.

Guys does anyone have a link or email address to supplier who could supply correct lenght and thickness of the spokes as i would like to rebuild my wheel with addition of sram automatix.

Could someone point me into right directio what lenght and thickness of spokes i have to order to work well with sram a2? I plan to retain current stock kinetix rim