SA 3 SPEED HUB AND 2 SPEED CRANK ???

[tee-one]

Im building a slightly different tourer style bike, And its currently spaced for a SA aw hub...

My original plan was to squeeze a 5 speed screw on hub in the rear, run a mech and so on...

But the initial plan was reliability. Now i see a few problems. Fitting a mech to a bike that shouldnt have one just brings up other issues and might throw reliability out of the window...

Sooo That got me thinking about running a 3 speed hub as per usual , But then fitting a crank with two chainrings and a front mech, Giving me basically a 6 speed...

Ive got a kore chain tenioner i could run too.... Or even buy something else if that causes problems...

I just dont want to spend hundreds on a new 5 speed SA hub


But thats got me confused... Ive got a mental block going on, And for some reason i can forsee problems with this but im not sure what...

Any ideas guys?

 

[barry2017]

An SA hub without a double chainring?

They have a really good range of gears when you get over the idea of using them like bikes with lots of gears. They're actually closer to singlespeed bikes than derralieur ones. When it all gets too hilly, just walk for a bit. It's not the end of the world for touring.

They're super reliable, easy to maintain (there are lots of AWs that have done 50,000 miles with nothing more than a teaspoon of oil per month), and they're cheaper than potatoes. The Sturmey AW is far and away the best designed hub ever.

 

[tee-one]

yeah im used to sa hubs... Got 6 bikes with em atm... Grew up with them.... Its sorta the reason id like to keep it part of it.

I do love the things. Reliable, simple , easy to work on and take some serious abuse..

Problem round here is the hills. Im in a dip. I dont mind riding SA equipped bikes mile and miles unloaded, But loaded with kit, It sorta takes the fun out of it. And makes it more of a chore.

The only one i find fun loaded up and touring is my rsw. Or my tenspeed puch.

Think i might just 5 speed it and see what happens. Then get a 3 speed wheel laced up while i ride it. Ive got another frame to put the 3 speed into.

Having a front mech would probably cause more issues than a 5 speed rear.

 

[barry2017]

If you must, you could fit a Dacon driver. Then you'd have both.

 

[tee-one]

not much chance of me finding one of those is there

 

[barry2017]

They come up all the time! Just go to a few cycle jumbles and you'll find one.

I'd still just use a smaller ring up front, and have gear 3 as the one to use on the flat.

 

[one-eyed_jim]

The basic idea's sound enough. I used to run a Brompton with an AW on the back and a Schlumpf Mountain Drive (equivalent to a wide double chainset) on the front.

One problem is that once you're down into a useful low range on the small ring, you're exceeding the loads the hub is designed for. As Chris says, if you just set top gear to around seventy inches and resign yourself to spinning out on the downhills, you get a climbing gear of around 40" from a standard three-speed, and a 24" gear (two feet) if you need to bail out.

Taking the idea a step further, an FW or S5/2 hub gets you a bit more range. You'll pay a bit more for an FW and a bit more again for an S5/2 but neither should break the bank.

Another option is to look at Brompton parts. I'm out of touch with that market, but I believe they sell a kit to convert a standard hub-geared model with the addition of a two-speed rear derailleur. If you're thinking of a rear tensioner anyway, you might as well get it to earn its keep.

 

[Jonny69]

I ran through Eastleigh yesterday by mistake when I got lost on my run. Added a few extra miles by mistake. There aren't any hills there, you big homosexual

The only thing I can think of is you're going to need a rear deraileur or something anyway, to keep the tension in the chain, so you still have the problem of mounting all that stuff up. So you might as well sling a 5 speed on, in my opinion, with a nice old clamp-on friction shifter or something.

 

[tee-one]

I ran through Eastleigh yesterday by mistake when I got lost on my run. Added a few extra miles by mistake. There aren't any hills there, you big homosexual

The only thing I can think of is you're going to need a rear deraileur or something anyway, to keep the tension in the chain, so you still have the problem of mounting all that stuff up. So you might as well sling a 5 speed on, in my opinion, with a nice old clamp-on friction shifter or something.

Yeah think im going the 5 speed route now , Just trying to plan the best way of respacing the rear for it.... As for shifter i was actually thinking i might modify an old SA gripshift for it.... :?

 

[fatfixie]

not much chance of me finding one of those is there

Many pre 1950's AW's came with threaded sprocket drivers which would let you fit a modified 5 speed freewheel if fitted with a 6 1/4" axle

a Sachs/Sram Orbit/dual Drive hub would be worth playing with also.

can i throw the cat amongst the pigeon and say the sachs Torpedo 3 speed hub is better designed than the AW

Andy