Belt Drive vs. Chain on Electric Bikes

In order to keep belt drives affordable, many electric bicycles use them with a hub motor and can only offer a single speed. Alternatively, you can get gears by using an internally geared hub like the Shimano Alfine or Rohloff, or a continuously variable transmission like the NuVinci (N360, N380, Harmony). These systems add weight and make it impossible to also have a hub motor in the back... so you either need to move that hub motor up front or go to a mid-drive setup.

[gepardtilly]

We have both in the family, chain and belt ebikes, all with Aldine 8, Shimano Steps and Di2 . At the beginning I was really all in for belt, but on the long term it has many issues, too. The tension has to be super well adjusted, and it's more difficult to remove the rear wheel and put it back because of the high tension. It's almost impossible to change the gear ratio, because different cogs need different length belt, which is either possible or not, but usually there is only one possibility offered by the shops, and they are not willing to experiment. Chainguard is still needed as it gets dirty, too, not oily, but dirty. Also because of the wider spaces needed both in front and back, to keep the belt straight, not all bikes can be made belt compatible. At the moment I find the chain is easier overall, I add a chainguard, and tolerate the cleaning and lubrication.

[Snoekvisser]

Chain stretch, grease, noise, derailment, just a couple of reasons for me to convert to belt years ago for daily commute year round. Been a fan ever since. Good video with lots of good points if you are on the fence.

[terry]

2.33 years later and it's delightful to look at how much more available and affordable IGH options have become, compared to when this video was made.

[gregmaher]

Rohloff and Pinion gearboxes are becoming much more popular now. Time for another video? Love your in depth explanations.
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[KillMD]

It is possible to use pinion gears or rear gear hub ( nexus or so)

[Michael-wnjj]

Riding a pedelec with Gates CDX drive belt since 4400 km. I'm still very satisfied about it. I rode it in -5 to +42 °C wet and very dry urban and gravel ways this year. Never did any adjustment or special cleaning to the belt Just cleaned it by bicycle cleaner and water like the rest of bike. That bike has a vertical drop out therefore removing rear wheel and placeing it back is no problem at all, Also it's good that this bike came with a "chain" protector so not everybody will notice the belt giving some protection against vandalism or by accident.
I like the fire and forget feeling of that drive system which matches perfectly to the almost maintenance free Shimano Nexus/Alfine hub.
One thing you should consider is to carry a spare belt with you on long distance trails because not each bicycle store has a matching spare part in stock.
So looking forward for the next care free 15000 km.

[liaminrio]

Im under the impression that belts produce measurably more friction than chains. Also they cant be repaired like a damaged chain can be. To me, belts are for people who don't like bike maintenance. Ditto for Nu Vinci hubs, which both weigh more and have heaps more friction than a derailleur setup. Great channel.

[brogen]

Can you coast downhill on the electric chain belt bike ?

[effyleven]

Hub gears don't need to be continuously variable. My Nexus is 8 speed. The correct place for the motor is in the bottom bracket. Then it can get use of the gears, whether belt or chain driven.

[BikeGoddessBikes]

I love the belt drive on my Faraday Cortland. It’s clean and quiet and easy to maintain.

[christill]

Personally I would never buy a chain drive bike again unless I was forced to. For example a Brompton doesn’t currently offer a belt, but it runs a chain with an internal geared hub so it’s bearable. But personally I hate derailleur systems. They go out of alignment, crackle, get covered in muck and need constant maintenance, which I can’t be bothered to do. People don’t maintain their car engine after every drive so I’m not doing the same with my bike. And it’s probably a big reason why so many of the bikes I see people riding are so destroyed, because people have no clue how to look after them.

Belts look cooler, are cleaner, last longer, are quieter, won’t come off. The weight on an ebike is completely irrelevant. My R&M Delite weighs 30kg. Would I notice the difference with a chain? Not at all. If I was going to put a nuvinci and a belt on a top end road bike, I’d definitely notice it, but not on an ebike.

As you say, RM have proven that you don’t need the gap in the frame and everyone else should go in that direction.

[jonneilsmyth]

is there a old sturmey archer hub cog sprocket i can get or does the whole hub need ripped out from scratch ??

[LynnRecker]

One other way to make the belt drive into a variable speed bike is to use a Pinion gear box at the crank. But I guess that is rather expensive.

[grumpynerd]

Actually, oil or grease on the *outside* of your chain doesn't do anything but attract dirt. Where it needs to be is inside the moving surfaces. The problem is the lubricant moves away from where it is doing work to where it does mischief. The answer to this problem: lubricate your chain by immersing it in molten paraffin wax (you can google this procedure). Wax does a very good job of lubricating the chain, and it stays put, resulting in a much cleaner drivetrain and less frequent maintenance. It is a bit of a bother to do, involving bars of wax and double boilers. There are commercial preparations with wax particles suspended in a solvent that you apply like a wet lube. You apply them, wait for the solvent to evaporate and then work the chain to flake off any exterior wax. Presto -- dry chain.

[ferryengr]

A couple of issues with belt drives.

(1) The commonly available gears and cogs for belt drives is more limited - meaning adjusting gearing for your local terrain can be more difficult. With a chain drive, (be it a derailleur or IGH), you can easily change the chainring and/or cogs to adjust the gearing - like if you have a lot of steep hills (e.g., Seattle or San Francisco).
(2) Combining a horizontal dropout to adjust tension for a belt drive, can cause alignment issues for disk brakes. The rotor on the wheel needs precise alignment with the caliper mounted on the frame. That is not easy when you use a horizontal dropout. Therefore, many bikes combining disk brakes and internal gear hubs (with no derailleur and therefore face the the need to adjust chain tension) use vertical dropouts (to fix the location of the wheel) and an elliptical bottom brackets to adjust chain tension. Because of the use of horizontal dropouts, the belt-drive bike you showed has a rim brake - a bit of a downgrade in my mind. (If it were to have a disk brake in back, you would face a problem. If you take the rear wheel off to fix a flat, getting it back on and perfectly aligned with the disk brake caliper could be a chore.)

[chrisgavin]

I've got the Gtech 'Sport' e-bike. It's a very basic entry level e-bike sold here in the UK. The one and only interesting thing for such a low-spech bike is that it has a Gates Carbon drive belt instead of a chain as standard. It's got a basic rear wheel hub motor and no gears. I've been riding it mostly for commuting to work and I have to say I love it. The belt drive is quiet, never oily and as the bike is already four years old (I bought it second hand earlier this year.), clearly pretty hard-wearing. The bike is obviously designed for the belt drive, with rear-facing wheel dropouts and a removable plate in the rear fork for replacing the belt. I have to say I'd definitely look for a belt drive whenever I move on from this bike, ideally teamed with some kind of hub gears and probably a centre drive motor. I think that would be a winning combination, something like that 'Priority Embark' model I've seen reviews of.

[krazykangaroo]

I have a Redline chopper with belt drive anyone know where i could get a spare belt? Problem is it's 2 or 3 times longer than the norm

[rocker]

Might be a stupid question, but where exactly is the battery on these bikes?

[carlbeaver]

Weight difference - Do you normally use a laxative before riding? About the same difference.
Efficiency - If you're on an e-bike do you really think it matters? If you're competing in the Tour de France, maybe/probably. On your way to work and stopping for a donut...?
Do you always remove your rear wheel to fix a flat? - Usually a waste of time and not necessary.
How many people with an electric bike actually use all the gears of a derailleur? A single-speed hub motor or a 3 speed IGH with a mid-mount makes more sense, chain or belt. If you really need 7+ speeds why would you need/want an e-bike? Then your weight concerns become valid, toting the weight of the motor, battery, etc.
Reliability - Never had a chain break or lose the clip for the master link?
Spring loaded belt tensioner? That would be more expensive and you'd probably need to carry a long prying tool to overcome the spring tension. Simple is better - slot with drawing screws. Best would be an extended axle that allowed the belt to ride outside the stays.

[Xanduur]

What about an internal gear system like Shimano sells?