http://www.sturmey-archer.com/en/products/detail/cs-rk3-black

Building a mid drive electric assist longtail cargo bike. Which certain folk will be glad to hear ive kept legal wrt to motor power and max assisted speed…..

But part of this means i cannot have more than 1 ring upfront and its limited to being bigger than a 42 because of the motor.

To keep it usable as a bike ive been looking at sram dual drives – then this popped up (ps i know peterpoddys selling -a dual drive but his is 36hole and i dont have any 36hole rims lying about :))

Anyone got any experiance with these hubs ? How do they last under torque and load ? I know the seallings a bit crap but its not going to be an offroad bike- its about 3 weeks long….

Bike Friday have run them on tandems for years, so I would have thought that they can handle the torque.

didnt know that – how ever that puts my mind at ease a little.

any more thoughts about them on a monday morning ?

Mick must have used one – hes got the entire back catalogue of SA at one point or another 😀

Used to see hacks of this 30+ years ago, old guys on touring bikes using freewheels on respaced/bodged SA 3 speeds.

With a triple on the front.

The mind boggles.

TBH, with a power limited electric motor and a 42T ring, you’ll never come anywhere near the torque limit of the hub.

Everyday is a school day, could quite see myself getting one of those for an on/off road tourer.
Oddly enough I only realised this weekend that one of my dad’s bikes has a mash up 3 x 3 version.

I use a lot of Dualdrives on various things, including cargo trikes – they’re also used on Maximus rickshaws. Very tough hubs.

I’ve used a few of the Sturmey version with no problems, but I have less experience of them.

they’re also used on Maximus rickshaws. Very tough hubs.

It was their rickshaw use that had me question their durability .

seemingly the dual drives can last as little as 2 weeks on the rickshaws…. – acording to some rickshaw e-zine i ended up reading last night.

Hmm, I doubt they’d keep using them if that was a regular occurrence! I’ve got one in the shop at the moment on a Maximus I’m converting to electric assist – ironically by removing the (quite old-looking) DualDrive and replacing it with a hub motor.

well i just bought the electric assist gubbins today for my cargo bike so will see how the gearing is when i get home next week and get it built and tested.

Will get the hub afterwards if needed – dont really want to give up my big un rear hub if i dont have to but if i do it will likely be an SA for replacement !