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Comment by leoh | Hacker News Reader

Great chain, but the Gates Carbon Drive is likely a superior technology. Europe has largely adopted it, but it is rare in the states. I have a Riese & Müller bike with a Gates Carbon Drive and it is absolutely lovely. Silent, but best of all, no grease on my pants or hands, ever. They handle dirt and dust super well (just dry off and wipe down with a cloth/no gears get jammed with a sealed planetary gear system). It also is said to last thousands of miles, if not 1e4 miles+.

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I live in the Netherlands and have traveled Europe very extensively and I have never seen one single belt driven bike... I have a feeling that it'll be a long time before Europe widely adopts them :)

Does look very cool, though.

"Largely adopted" also avid cyclist both in the city and in the countryside, and I don't recall seeing one of these ever

I've seen many, but only in shops. On the road they just don't look that much different, they are the kind of bicycle that doesn't draw any attention and you surely won't see any parked because they are way out of street parking price range anyways (particularly in the Netherlands were most bikes don't even cost as much as the belt itself because returning home on foot isn't much fun)

Oh, but you can see those from time to time Belgium. Largely adopted? No, not at all.

Cube has one https://www.cube.eu/en/2020/bikes/urban/hyde/cube-hyde-pro-b... , I bought the 2018 model it's really nice and convenient to drive. Going back to traditional chain once you drove one of these may be similar to automatic vs manual gear shift in a car, why would you? Note: I'm a casual cyclist.

Nicolai make some nice ones

Nice one, thank you. Love the 2021 models colours.

+1. I've owned one in Europe for 11 years, and during that time never met anyone else who had one and very rarely even anyone who had heard of them.

But a Rohloff + a carbon fibre belt is an absolutely dreamy combination for anybody who prioritizies reliability. I'd buy a new one in a heartbeat if my current bike got stolen.

I've seen quite a few of those here in Toronto. One owner I've spoken to actually said that it has noticeably higher friction. I did not try those bikes myself so can not really confirm/deny.

It has higher friction at low speeds, but has better power transfer than a chain once up to speed.

I’m Dutch and have a belt drive on my e-bike. They are mostly used on high-end (read: expensive) bikes.

Great system though, completely silent.

If you want to shift gears using the carbon drive you have to use an internal gear hub, which has a lot less range than a traditional derailleur and is less efficient. So if you are riding a racing or mountain bike a chain system is probably a better way to go.

Also it looks like you can't shift under load with the internal hubs which is a problem if you are trying to climb hills quickly.

> a lot less range

Maybe in the more popular implementations like from Shimano. But there's internal hubs with greater ratio spread than chained: The Rohloff:

https://www.sheldonbrown.com/internal-gears.html

...which at ~€1100 costs more than many people will spend on a bike, weighs more than a full set of sprockets and a derailleur, is less efficient due to the staged planetary drive, can only be repaired by sending it back to the factory, can (like other planetary drives) not be shifted under load and as such is more of an interesting novelty than a real solution to the stated problem.

Good internal hub gears can be shifted under load, and the Rohloff one is probably as good as it gets.

The Rohloff can not be shifted under load. You can shift by quickly letting off power, shift and then resume like you can do with other planetary gear systems.

Here's a discussion on the subject of shifting under load, with opinions from "both" sides:

http://thorncyclesforum.co.uk/index.php?topic=4172.0

I ride a Rohloff and you do not shift them under load. Most of the shifts will tolerate a light load, but going from 7-8 while steaming up a hill will immediately bind the gears and you need to backpedal a few teeth to get it unstuck. By the time that's all sorted, you've lost your momentum and need to downshift again, not to mention taken months off of the lifetime of your very expensive hardware. As you can probably tell from my description, this is a mistake I've made. Binding up your brand new $1500 transmission is a great lesson to never do that again.

All the gears on an internal hub are usable, there's no overlap. These days the ubiquitous Shimano Nexus hubs can shift under load. For the kind of bicycle most people buy they are a reasonable alternative because there isn't a fragile derailer, there's no double shifting, and the adjustment is static alignment of two yellow marks.

In terms of friction, there are no jockey wheels and the chainline can be perfectly straight. Anyway, the internal friction of a geared hub is going to be unnoticeable for an average cyclist because the tires will be under-inflated, the chain covered in crud, and the brakes will be rubbing on untrue wheels.

But like everything it's a tradeoff.

You can't/shouldn't shift under load with a derailleur either. Pinion gearbox has an option of 18 gears with a 600%+ ratio while something like SRAM Eagle 1x12 has 500% ratio. I don't know about the efficiency but i think something like this should be the future - https://www.pinkbike.com/news/allen-millyard-part-1-2008.htm... or maybe there is proper reason why nothing like this has come into the market - shifting without pedalling or under load, closed system (don't care about dirt/water) and no noise.

Depends on the IGH. Nuvinci and Schlumpf definitely can.

The efficiency (like all other marginal gains in cycling) is important for racers or long-distance tourers. For everyone else it needs to be considered against the maintenance burden required to maintain an exposed drivetrain which needs to be cleaned, lubricated and adjusted in order to maintain its relative efficiency.

And weight...

My Pinion gearbox has 12 gears and a 600% range; about as much as a 3-chainring derailleur system. You can get them up to 18 gears and over 636%.

It is less efficient (apparently). But at least it's consistent. Ride a chain in the rain for just a couple days and trust me, it's nowhere near that theoretical 95%.

My previous bike had a Shimano Nexus 8 speed. It would shift just fine under load. My current bike has a Sturmy Archer 3 speed and doesn't.

Geared hubs are great for riding in traffic because you can shift while stopped. Pulling harder with traffic up to a light and braking aggressively, and switching to the right gear while waiting for the light to change.

Like everything it's a tradeoff. For me, geared hubs make a bicycle a more useful tool. Less fragile. Less maintenance. Idiot friendly static adjustment.

8 speed is a bit delicate to shift under load, if you plan on doing that a lot a 5 speed would be a better choice (also better for e-bikes, it will deal much better with the torque).

The older I get, the more willing I am to use tools and accept that it will eventually wear it out. I put about a thousand miles around town in a year on it. The whole bike was $500 new with shipping. Never destined an heirloom.

The Nexus eight speed is the seven speed with a “granny” gear. The seven high gears have small steps relative to a five or three speed. I suspect this might make shifting under load less stressful on the components...note that under load shifts are always just one gear at a time unlike a derailer.

The Nexus 8 is a great piece of kit. Robust, inexpensive and stupid easy to tune.

Gates only quote between 95-98% efficiency. You can relatively easily get to 98% with conventional chains using wax and oversizing chainrings and sprockets and you don't need to worry about splitting your frame to replace them...

This is a very niche product but sounds like an interesting approach. The users of it likely won't care if it needs replacing every ride if it means saving watts and winning (olympic) races.

> Europe has largely adopted it

I'm not sure you're using the term "largely adopted" correctly. It implies that something is the majority or norm, not a rare occurrence.

I've got a belt-drive "commuter bike" that doesn't get ridden much these days. It currently has a Gates Carbon Drive which I mostly like, and you're mostly correct. But it came with a Continental belt drive system that was awful. I snapped my first belt on it under load when it was about 6 months old. The damn thing always squeaked no matter how clean i tried to keep it. The rear wheel had to be on perfectly straight or sometimes the belt would slip one way or the other -- and of course, belt tension is very hard to get right. I think the gates system operates at lower tension than my continental did, which is a plus.

I hope the Gates belt is stronger than the Continental one, but I don't know for sure.

I think Ghost ultimately was willing to goodwill replace the continental trash with a complete Gates drive system because a continental belt could not be sourced anymore. But, I still have to worry about the nightmare of axle nuts, belt tension, removing the tiny nut from the hub to disconnect the shifting, and removing the brake caliper (!!!) to fix a flat.

Sounds like your next thing is to switch to tubeless tires so you don't have to do that so often

I've destroyed a number of Sturmey Archer planetary drive clutches - the square cross-shaped bit which transfers force from the sprocket holder to the drive - by just using them, leaving me wary of planetary drives. While I've also gone through derailleurs they do seem to handle power better than planetary drives and have the additional advantage of feeling far more like a direct drive. One of the advantages of a bicycle is its simplicity, there is not much between your feet and whatever goes for road you happen to be on. I'll gladly give up 2% of efficiency to keep the system simple, repairable with off-the-shelf parts which can be found anywhere in the world and affordable.

Then you're a stronger cyclist than me, because I've ridden S-A AW hubs for decades and have broken Zero of them. I've have had them open to determine that they tend to stay in pristine condition under normal use.

But the common IGH's do come with specs for minimum gear ratio front to back (2:1, I think), suggesting an implied torque limit. I've always wondered which part was the weak link.

The cogs wear out under normal use (I've replaced a couple so far) but that's true on derailleur bikes as well.

> I've always wondered which part was the weak link.

Well, now you know... especially in 3d gear (when the cross drives the planetary hub by engaging on the top of the cog axles) the clutch is under high load. I often rode that bike with a heavy trailer (made from a shipping crate and some moped wheels which I happened to have lying around) to haul my guitar, amp and saxophone through the Dutch countryside to practice with my band, this may have put too much of a load on the hub.

I'm a double bassist, and have only seen pictures of people cycling with their basses, but they are all either from the Netherlands or NYC.

How do you handle gears with the belt? Most of the bike I've seen in the US that use the system are single-speeds. I suppose you could use a internally-geared hub, but a Rohloff is mega-expensive and the Shimano offerings leave a lot to be desired.

I bought a Spot Ajax with an Alfine 11 speed hub. Shifts well and has a good spread. I’m a recreational bicyclist though, I have no idea how it “performs”.

For recreation/commuting/city use, the Alfine is fine. Unless Shimano has revamped it in the last few years, it isn't particularly robust and doesn't work well for high-power use (mountain biking, in particular).

They're going onto e-bikes that will never be pedaled under human power.

The advantage here is that the chain could be made backwards-compatible with existing conventional drivetrains. The Gates drive can't be retrofitted onto older frames.

Why can't it be? My bike is a fixed gear track frame. If the threads of the sprockets are compatible with the rear wheel, then it should be able to fit.

The belt is a closed loop and under high tension when installed. Your frame needs to be able to be opened to let the belt in, then your sprocket pack needs to be able to move backwards, so you can put tension on it.

> then your sprocket pack needs to be able to move backwards, so you can put tension on it

I am assuming that's what the poster meant by putting emphasis on his frame being a fixed gear one. Those normally have horizontal dropouts to put tension in the chain.

Thanks, I had no idea!

But they don’t have split frames so there is no way to install the belt in the first place.

Unlike a chain the belt is a closed loop, you can only use it with a frame that can be opened in the rear triangle.

There is however a belt drive systm with a split belt. Seems to be quite new and expensive and propably come switch its own upsides and downsides.

I have seen maybe one driveshaft based bike, and I’m European, and that was at the school of mechanical engineering.

It is a belt drive system, not a driveshaft-based system.

There was/is? a danish company building those, seems they switched to belts though.

Any idea of the sustainability of the Gates Carbon Drive system? Looks like it's made of polymer + carbon fiber. On the other hand, traditional chains eat+shed oil and grease.

My Gates carbon belt is like new after 8 years riding my Schindelhauer Siegfried. I seem to remember 10 years quoted when I bought it.

Mine is 5 years old still going strong and I commute everyday. But check this guy https://www.cyclingabout.com/belt-drive-best-bicycle-drivetr...

I disagree both about the adoption rate and the superiority of the tech. It only works if the frame can be opened up and this means the whole bike has to be designed around the belt drive system. It's a slow thing to do and quite expensive, whereas replacing a regular chain takes less than five minutes (it's a bit more messy though).

I have to be honest, when IKEA launched the Sladda, I had high hope that they'd sell a zillion of them so I could pick one up barely used for a pittance in a couple years. Sadly, that seems to have not happened, and we'll have to wait a bit longer for the belt drive to become commonplace :-(

Wasn't that the one subject of a recall because the belt could break? Recall for refund, not for repair. So a complete failure.

Ugh. I missed that. Bummer!

I wonder if the frame wasn't built to allow belt replacement?

I have a Gates Carbon drive too. It's extremely convenient, but my understanding is that it's lower efficiency compared to a well-mantained chain. Due to the practical challenges of maintaining a steel chain, I think Gates does well and it's a great commuter option.

> Europe has largely adopted it

I live in a very bike-friendly European town. I use my bike daily. I have seen maybe 10 if these things in the last 3 years, mostly owned by elderly people who were sold high-end e-bikes they don't need.

What about potential of the ceramicspeed driven design? https://www.ceramicspeed.com/en/driven/

I cannot believe that thing is viable.

It appears that it currently is not...

Some cyclists are indoctrinated to the point that they might actually buy this insanity.

HN is becoming more conservative by the day. Shouldn’t companies/people be applauded for thinking outside of the box and trying to innovate?

Innovation can be good, scamming other people into spending money on things that don't work, not so much. There's a whole lot of the latter masquerading as the former. There's also a whole lot of user/customer/community hostile innovation, like the entire advertising industry.

That’s not the case here though. The design I linked is a legitimate attempt at solving a real problem. Whether it works as well as intended or not is a separate issue.

The design as plain obviously wrong. The only "legitimate" part there is trying to part people with their money for zero benefits.

I'm not a mechanical engineer or anything remotely like it. Can you explain why the design is wrong and especially explain why you think it's a dead end that can't solve it's problems via iterating?

This drive train simply can not handle high torque as the chainrings will bend under load. They admit it themselves. Increasing their thickness will cause a whole lot of compatibility problems and also turn the whole thing into a monster.

This expensive ceramic bearings are exposed and will experience significant wear. Properly insulating them would wipe out whatever miniscule gain in efficiency they claim as the insulation increases losses.

Finally reducing chain friction (which is already very low on a tuned drivetrain) to some fraction (that has yet to be proven for real conditions) is tantamount to snake oil in my opinion.

These are just few. I could go on but it is not worthy the typing and mental efforts.

As a counterpoint to all the other comments: EU, my electric bike has a belt. Most high end electrics do. Might not be the same outside of the cycle countries (nl, dk...).

> Europe has largely adopted it,

I'm an avid leerer of other's bikes, and in my long and fruitful bike leering career in Europe, I have seen just one (1) gates drive.

>Europe has largely adopted it

I'm a European cyclist and only ever seen conventional chains.

not as efficient though

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