MadProphet

I was recently looking at a Spot Acme and noted they had a Gates/Alfine driveline and was wondering what folks thought of the combo over all. Last year, mainly cause of my back and associated issues, I was on a recumbent trike and a lot of the high end there is drifting toward a hub-based setup. No belts - yet. I don't see much talk of it here, though I have seen some on MTB forums and all.

I've never liked chains and the attendant gear and really like the idea of a belt with hubs. The Spot Acme had a single ring up front, which I'd want to adjust to a Patterson or Schlumpf but I can see working with that setup for a few years.

How's changing a tire with that setup?

fietsbob

https://spotbrand.com/bikes/product-page/?shopp_pid=23

Belt drive basics. that builders have to sort out
#1 the frame has to open up, since the belt wont.
how are you going to tension the belt?

vertical dropouts make wheel removal easy,
Rohloff's external shifting gear box is easy to remove.
[and the gear range is adequate]

getting Shimano's single Alfine, cable out is less so.
(it wraps around the hub on the right side, setscrew- cable clamp barrel, in a groove)

FWIW, I have a Schlumpf Mountain drive with an AW3 hub, its on my Brompton
3 becomes 6 speeds , no overlap.
Rohloff does that internally, it's 7 speed is used twice.

With the IGH internal torque limitations, only Schlumpf you can fit is their Speed Drive
1.6X overdrive, then you get Huge gears , on the top end, few practical, day to Day

MadProphet

I'm not going to try to modify my Trek, if that's what you were thinking. Rather, add to the stable. Or sell the Trek. I know Patterson or Gates has a mod for the Patterson to fit a belt, so if you were talking about the Spot Acme, I'm thinking they have it covered.

Tensioning is one of the issues I've read about. I imagine the frame has vertical dropouts - is that all that's needed for tensioning? The Rohloff is SIGNIFICANTLY more expensive then the Alfine 11, so I doubt I'd be going the way of the Rohloff. I was just thinking perhaps (specifically) of the Spot Acme with the addition of a two speed crank and (generally) how people find the use of the belt and hub system. But yeah, a Schlumpf and Rohloff geartrain with a belt - sweet.

fietsbob

I have a Rohloff (2 actually) , in a 26" wheel the gear is a 16:38,and is as low as they allow, in warrantee.

and the 20" wheel Bike Friday, it's a 16:53 and is the same gear range.

and being greater than 1:2.4, actually climbing gears put less torque strain on the internals..

Schlumpf is Swiss , Rohloff German ,
my Mountain drive was $700. so adding that speed drive, aint gonna be cheap either
1st bike I got Used, was just $2K with the R'off , a Koga WTR, from '04.

if you work with your LBS, they can sort out a 'take-off' deal for the stock 11 speed,
and you can apply that to the R'off (I got a 2nd hand one for $800)

they now make a 36 and a 32 spoke hole hubshell ..
so it is possible to keep the rims and re-spoke the hub in..

FBinNY 

Chain drive definite has a place, but it has limitations. The earlier Gates belts had wear issues in heavy use, but maybe the newer belts are better.

Despite improvements, I don't think belts are well suited to heavy high mileage use. They also don't handle high loads well so you might not want a belt drive if you ride in hilly terrain.

That said, if the benefits of quiet running and cleanliness justify the added replacement cost, then a belt may make sense for you. One note, recumbents use odd length chains, so unless an OEM has enough volume, I doubt you'll see Gates tool up and produce a belt for them.

fietsbob

They are showing up as Crossover drive on Tandems.. if the Redistribution starts working
so more people have a bit more Dosh, it certainly is mechanically possible to
even break up a long Recumbent driveline up into shorter belt lengths
by a double cog , jack shaft, to run 2~3 belts instead of one long one..

The hubs for Tricycles already have a Cog instead of spokes for 1 flange,
to run a second chain at a different ratio than the input

and as 4 bolt Chainrings run where the discs Mount, in Rohloff use
and several others do similar , the counter shaft as a crossover, is also a gear box.

MichaelW

Vertical dropouts need a means of belt tensioning, either by sliding vertical dropouts of an eccentric bottom bracket.
Belt drives have been used for round the world speed records using Rohloff and Alfine hubs. This is one of the most punishing tests, covering 80-100miles/day for months on end.
The issue of an opening frame is an easy one to solve but most of the solutions are only found in custom or high-end frames. I would love to see some affordable factory frames setup for belts.

HillRider

Your wish is our command:

https://www.trekbikes.com/us/en/bikes..._utility/soho/

https://www.specialized.com/us/en/bik...roll/roll8rare

pierce

It sure doesn't look like the chainstay on either of those bikes has any way to 'open' it to replace the belt?!?

as close as I can zoom on the Roll8, it looks to me like the chain and seat stays are both welded to the U loop that holds the hub adjustment, and the trek looks much the same from every available angle.

edit: ok, looks like Trek does have a solution,
https://www.gates.com/ptdesign/trek.html

its just not evident from the pics on their site, heh.

edit2: oooh, and I see a joint on the seat stay up by the brake on the specialized Roll. sneaky.

Looigi

I'm not particularly knowledgeable about this but I am aware that Gates has two kinds of belt drives. The newer, and presumably better/more durable is called CenterTrack and has a ring that retains the belt axially with a ridge in the center of the teeth rather than end plates, and a belt with a matching slot down the middle of the teeth.

Paul Ebert

A few other options:

https://www.breezerbikes.com/bikes/de...ltway_infinity

https://www.rei.com/product/825377/no...tham-bike-2013

What I'd like to see is a Surly Ogre that could take a CenterTrack.