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Re:Ceramic-bearing bicycle drive shaft (2018) by wlkr on Friday August 16, 2019 @06:23AM (#20713722)
I think the biggest innovation of this kind that I've seen in use (anecdata, of course) is the number of commuter bikes fitted with belt drivetrains (Gates Carbon Drive) paired with internally geared hubs. The reduction in maintenance effort is purported to be significant and it's not only limited to high-end bikes (plus it can be retrofitted although non-trivially for the majority of frames). When the cog wear becomes too bad on my single-speed I'll look into fitting a belt drive, if possible.
Re:Ceramic-bearing bicycle drive shaft (2018) by vinni2 on Friday August 16, 2019 @11:19AM (#20716035)
I have been using a bike with belt drive for about 2 years and while the lack of chain reduces some maintenance doing other maintenance like switching tires gets more complicated.

And of course the loss of efficiency due to belt drive is also pretty bad.

I am convinced that this will be my last belt drive bike.

Re:Ceramic-bearing bicycle drive shaft (2018) by pkulak on Friday August 16, 2019 @12:13PM (#20716649)
If you're a tinkerer, and you like swapping tires, doing all your own maintenance, etc, then I agree with you 100%.

However, my bike is my car. I'd no sooner swap out my own bike tire than I'd swap out my own car tire. Not that I can't, it's just not something I enjoy doing. My hub-geared, belt drive, hydraulic-disc bike is incredibly difficult to maintain... but I also just bring it in to my local bike shop once per winter. That one trip is all the maintenance it needs for the 3200 miles I put on it per year, mostly in the rain. I'd never go back to lubing a chain every week, putting new pads on every month, replacing the chain every 3, etc. 6 months after I bought this bike I gave away my repair stand and it was glorious.

Re:Ceramic-bearing bicycle drive shaft (2018) by sbierwagen on Friday August 16, 2019 @12:23PM (#20716758)
>I'd no sooner swap out my own bike tire than I'd swap out my own car tire.

In my neighborhood I get a flat every other month. If I had to pay someone else to replace inner tubes it'd cost as much as driving a car.

Re:Ceramic-bearing bicycle drive shaft (2018) by pkulak on Friday August 16, 2019 @12:28PM (#20716806)
What tires do you run? That'll happen to me unless I run touring tires. With Schwalbe Marathons front and back, I never get flats.
Re:Ceramic-bearing bicycle drive shaft (2018) by rconti on Friday August 16, 2019 @12:47PM (#20716996)
You can see my (lengthy) post here about my experience with belt drive, but I was CONSTANTLY getting flats on my Ghost; tried the tires it came with, added tire liners, added slime tubes, nothing worked well until I got the (heavy as a tank) Schwalbe Marathons. Now I want to get the slime tubes out but don't want to remove the tire to do so. But yeah, another vote for "not changing your own tires isn't really an option". Even though its virtually impossible to change tires 'in the field' on my ghost.
Re:Ceramic-bearing bicycle drive shaft (2018) by entee on Friday August 16, 2019 @04:14PM (#20719257)
There are also very tough plastic liners you can put between the tire and the inner tube. At some point picked up a 1 cm cut in the the tire that this inner layer not only prevented a puncture but kept the whole tire/tube/wheel together until I noticed it by happenstance weeks later. Search for Mr. Tuffy liner but there are others.
Re:Ceramic-bearing bicycle drive shaft (2018) by LargoLasskhyfv on Friday August 16, 2019 @09:57PM (#20721457)
Tried them, felt bad, was harder to drive. The same goes for stuff like Schwalbe Marathon. When i look back into the times where i bicycled more, i wonder how i managed with the tires which had just a thin mesh of wires embedded? I feel like the modern stuff has more planned obsolescence built in. Tubeless makes no sense economically to me, so i go with a small can of breakdown spray.
Re:Ceramic-bearing bicycle drive shaft (2018) by sbierwagen on Friday August 16, 2019 @12:33PM (#20716860)
Continental Top Contact II 37mm front, Continental GP Urban 35mm rear. (Rear fender has less clearance)
Re:Ceramic-bearing bicycle drive shaft (2018) by jspash on Friday August 16, 2019 @02:33PM (#20718133)
Have you tried tubeless? I've run them on mountain bikes for yonks, and have now done so on my (non-racing) road bike for about 2 years now with very few complaints. (My race-race bike is fitted with tubs)

They can be messy, but I've lost count of the number of self-healed punctures I've had over the years. A small loss of pressure and off you go.

Re:Ceramic-bearing bicycle drive shaft (2018) by MisterOctober on Friday August 16, 2019 @04:00PM (#20719107)
+1 for tubeless -- I switched a few weeks ago after getting sick of weekly punctures in Phoenix -- already saved me a boatload of time and trouble.

Currently running WTB Venture 47c [changed from Horizons] on a 650b 'gravel bike', fantastic stuff, gets me where I wanna go.

Re:Ceramic-bearing bicycle drive shaft (2018) by vinni2 on Saturday August 17, 2019 @02:10AM (#20722449)
> If you're a tinkerer, and you like swapping tires, doing all your own maintenance, etc, then I agree with you 100%.

Oh no not at all! I hate swapping tires. I live in an expensive and cold country. Swapping bike tires costs $50. I couldn’t afford that twice a year (because of winter tires) I have to do it out of desperation which is why it’s more work than the maintenance benefit I get.

Re:Ceramic-bearing bicycle drive shaft (2018) by Grustaf on Friday August 16, 2019 @03:53PM (#20719043)
I’m going to go out on a limb and guess that you are American. If you have quick release wheels and a new tube (rather than patching the old) you can literally replace a tube in 4 minutes. I’ve timed it.

If your bike is your main form of transport and you can’t change tubes, you need to have two bikes. Unless you live next to a 24 hour bike shop...

Re:Ceramic-bearing bicycle drive shaft (2018) by lampenrad on Friday August 16, 2019 @11:44AM (#20716304)
Another disadvantage is repairability. If your chain snaps you can fix it with a quick link or a pin and a little multitool with chain tool functionality. If your belt snaps you‘re screwed, unless you carry a spare belt everywhere.
Re:Ceramic-bearing bicycle drive shaft (2018) by pkulak on Friday August 16, 2019 @12:06PM (#20716565)
Has a belt ever snapped? Serious question. I've never heard of it happening, and the belt drive bike I've been riding for 4 years isn't even wearing, let alone close to snapping.
Re:Ceramic-bearing bicycle drive shaft (2018) by lampenrad on Friday August 16, 2019 @12:38PM (#20716918)
If you google gates belt drive snapped you‘ll find plenty of anecdata of belts lasting only a couple thousand kilometers (and others who ride them for tens of thousands of kilometers with no issues).

Here‘s a (German) Video from a guy with a severely damaged (but still rideable) belt after 4500 km:

https://m.youtube.com/watch?v=n16gN7RDWEY

In the comments you‘ll find people whose belts snapped at 1050 km, at 1000 km and one at less than 2000 km.

I don‘t know how likely this is, it might be quite rare. But since it‘s non-repairable it‘d make me uneasy on longer bike rides.

Re:Ceramic-bearing bicycle drive shaft (2018) by AceyMan on Friday August 16, 2019 @05:56PM (#20720100)
Same for me. My Focus Planet is a 2015 model and I ride nearly every day; the blue coloring on the tooth side (presumably a wear indicator?) is barely worn through at any point.

Mine also has the Alfine 8 speed hub, which is kind of suck, but I make it work. I recently had it re-lubed (dunked) at my LBS, which seemed to help. I just wish there were some nice IGH in between the Alfine 8/11 and a Rohloff. I'd gladly pay for something better than the Shimano.

For commuters, I cannot fathom why people would deal with a chain when belts are a thing. Plus, good chains aren't cheap (I like Wippermann) and when you rack up miles you need to replace them enough that your wallet notices.

Tires: +1 for Schwalbe Marathons. Four years and no flats. NB: if you are worried about weight, upgrade to the Marathon Supremes with the aramid (foldable) bead. ~$75USD/each but totally worth it.

Oh yeah: a dynamo hub is a life-changer. My Focus came with a SP PD8 and lights, stock. Never having to strap on a light, or remember to charge it is a revelation.

Ride safe!

Re:Ceramic-bearing bicycle drive shaft (2018) by npunt on Friday August 16, 2019 @08:00PM (#20720849)
Yes I snapped mine within an hour after delivery. It may have been too tightly tensed (tho I did check with the app and it was fine), or it may have experienced stress during shipment. Whatever the case, did not instill confidence. Never rode the bike enough to have much experience with long term reliability, but found the 11-speed IGH didn’t have enough range to cover SF hills appropriately, and shifting wasn’t reliable even after tuning several times - why they chose to implement as a mechanical pulley instead of precise internal system is beyond me. Big purchase regret all around.
Re:Ceramic-bearing bicycle drive shaft (2018) by Nelson69 on Friday August 16, 2019 @01:00PM (#20717106)
I've had a Spot ACME with belt for about 6 years. I've used in on my daily lunch ride 4+ days a week. I was worried about all that stuff, I love the bike and was worried about nothing.

Belt damage? They put these belts on motorcycles, it's possible to damage them but they are insanely durable, probably stronger than your typical chain. Somewhere I picked up a staple on mine, I'm going to get it replaced but I've done several hundred miles on it with no issues.

The IGHs are a different matter, they're pretty sensitive and if you get them off a little bit they work but your shifting will be hosed up. Bike shop fixed it all though. My advice? Don't mess with it, get it set up, make sure the little connector on the cable is tightly attached and you probably won't have issues, I had some slip on mine.

I've been running Conti touring tires with some mixed tread and pre-slimed tubes, I've not had flats but I've worn out 3 or 4 sets of tires. It's not a big deal to change it though. It's a commuter bike so it has bolts rather than quick release skewers, I'd use slime and maybe even kevlar liners if you get a lot of flats and just make tire changes a wear issue. It's a heavy bike, it's not a carbon roady by any stretch but it has been as close to zero maintenance as any bike I've had. It's actually required more maintenance on the disc brakes than the drive train, they were getting a little squishy but just rebleed them and they're good again. The only "issue" I've had was when I got a lot of dust on the belt, it was kind of squeaky for a while.

This carbon/ceramic drive shaft is kind of interesting. I always thought that the chain to pully and gear touch point was where the friction loss was, not interlink on the chain itself. For years and years, they've offered bigger pullies for reduced friction. This drive shaft will still have a similar touch point; also seeing as how both pieces rotate, it looks like there could be side to side friction as the cog on the shaft touches the gear on the wheel and they both rotate unless the cog and gear have some very special shaping that I'm not seeing. As the cog rotates, when it first can engage the gear, just the tip will be touching the gear but as it continues it will push more of the tooth on the cog in to the gear, am I wrong on this?

Re:Ceramic-bearing bicycle drive shaft (2018) by rconti on Friday August 16, 2019 @01:25PM (#20717368)
Heh, look elsewhere in this thread and I ALMOST bought an Acme but bought a Ghost instead, and had issues with the Continental belt drive (even before it snapped, it squeaked every time it got remotely dirty).
Re:Ceramic-bearing bicycle drive shaft (2018) by LargoLasskhyfv on Friday August 16, 2019 @10:40PM (#20721620)
That is something which is really puzzling to me. Why doesn't anyone protect the belt with something like this:

[1] https://www.hebie.de/en/protection/chainguard/chainglider/35... ?

Are bicyles a fashion statement, or what?

"Seht her wie geil mein Riemen ist!"

Re:Ceramic-bearing bicycle drive shaft (2018) by Nelson69 on Friday August 16, 2019 @01:36PM (#20717474)
I don't know about the Conti belt but the Gates has been rock solid since they introduced the center track guide. The first wave did have some problems unless the pullies had guides, they could slide off.

For what it is, I love it, it's not a racing bike though. I'm curious about the mtb uses with a Rohloff hub, it's a fair amount of weight.

Re:Ceramic-bearing bicycle drive shaft (2018) by rconti on Friday August 16, 2019 @12:58PM (#20717081)
I snapped a continental belt drive after 1000mi. It's been replaced with Gates. Hopefully it lasts longer.
Re:Ceramic-bearing bicycle drive shaft (2018) by pkulak on Friday August 16, 2019 @01:13PM (#20717213)
Those ones suck, apparently. Had to be recalled even, and totally shut down Ikea's bike.
Re:Ceramic-bearing bicycle drive shaft (2018) by cbsks on Friday August 16, 2019 @11:49AM (#20716360)
This is my experience with my belt drive bike too. It’s a neat novelty and it’s nice having one less chain to maintain. But I wouldn’t use it for rides over a few miles long and changing a flat is more involved.
Re:Ceramic-bearing bicycle drive shaft (2018) by usrusr on Friday August 16, 2019 @09:55AM (#20715142)
> (plus it can be retrofitted although non-trivially for the majority of frames)

Not at all: the chain goes through a closed triangle in the frame by connecting two loose ends. The belt comes as a closed loop and needs a frame that can be opened. Additionally, frames build for chain gearing (instead of internal gears or single-speed/fixed) lack tension adjustment by either a horizontally adjustable dropout or a bottom bracket excenter mechanism.

Re:Ceramic-bearing bicycle drive shaft (2018) by jdietrich on Friday August 16, 2019 @11:12AM (#20715943)
>Additionally, frames build for chain gearing (instead of internal gears or single-speed/fixed) lack tension adjustment by either a horizontally adjustable dropout or a bottom bracket excenter mechanism.

Sliding dropouts are undoubtedly preferable, but any modern frame with a BB30 or PF30 bottom bracket can be trivially converted to an eccentric bottom bracket.

Re:Ceramic-bearing bicycle drive shaft (2018) by jwalton on Friday August 16, 2019 @07:06AM (#20713935)
I'm interested in a belt drive, too, but mainly because I hate getting a greasy chain stamp on my leg. :P Belt drives don't need lube, so they stay pretty clean.

I'm surprised there are retrofit kits. With a belt drive, usually one of the chain stays has a gap in it so you can get the belt on and off (you accomplish the same with a chain by taking a link out to install/remove the chain, but this is not an option with a belt).

Re:Ceramic-bearing bicycle drive shaft (2018) by dotCOMmie on Friday August 16, 2019 @08:59AM (#20714702)
Bit niche but there is one company making split belt: https://www.veercycle.com/

But it's 3-5x the price of chain equivalent setup.

Re:Ceramic-bearing bicycle drive shaft (2018) by dsfyu404ed on Friday August 16, 2019 @11:40AM (#20716258)
Why not just use a normal belt and some way of tensioning it like every other belt drive in the world uses? Seems like the fancy belt (and more importantly, the fancy pulleys that go with it) drives up cost substantially.
Re:Ceramic-bearing bicycle drive shaft (2018) by sbierwagen on Friday August 16, 2019 @12:28PM (#20716810)
Look up-thread. You have to thread the belt through the frame. You either need a special frame with a gap in it, or a belt that can be split.
Re:Ceramic-bearing bicycle drive shaft (2018) by dsfyu404ed on Friday August 16, 2019 @12:59PM (#20717102)
I read that part. That doesn't explain why they chose that oddball cogged belt instead of a commonly available belt profile (cogged or otherwise) for which pulleys are available off the shelf (or cheaply built to order) and belts are dirt cheap.
Re:Ceramic-bearing bicycle drive shaft (2018) by adrianN on Friday August 16, 2019 @07:16AM (#20713989)
It's probably cheaper to put some plastic around your chain.
Re:Ceramic-bearing bicycle drive shaft (2018) by xavieralexandre on Friday August 16, 2019 @07:58AM (#20714220)
For a clean chain you can switch from a conventional lube to wax based lube. It’s a relatively involved process (You need to degrease your chain before application) but it keeps the chain relatively dry and clean. (Plus it’s slightly better performing than other lubes).
Re:Ceramic-bearing bicycle drive shaft (2018) by xchaotic on Friday August 16, 2019 @03:09PM (#20718577)
Scientific measurements or it didn’t happen. I think wax underperforms lube, prove me wrong.
Re:Ceramic-bearing bicycle drive shaft (2018) by flaviu2 on Saturday August 17, 2019 @01:05AM (#20722201)
https://www.ceramicspeed.com/media/3505/velonews-friction-fa...

See page 63 for efficiency and 64 for longevity.

The graph on page 64 is confusingly labeled, but the numbers indicate "watts expended before wet dirty run" - "watts expended after".

Re:Ceramic-bearing bicycle drive shaft (2018) by nordsieck on Friday August 16, 2019 @07:02AM (#20713900)
> commuter bikes fitted with belt drivetrains (Gates Carbon Drive) paired with internally geared hubs. The reduction in maintenance effort is purported to be significant

My understanding is that the tradeoffs are:

1. Weight

2. Cost

3. Lack of user serviceability.

It definitely seems like a good tradeoff in some circumstances - particularly in rainy environments.

Re:Ceramic-bearing bicycle drive shaft (2018) by maaaats on Friday August 16, 2019 @07:22AM (#20714029)
Or snowy with salt in the winter. For winter cycling the weight isn't really an issue for me, the bike is already sluggish with big studded tires and accessories and clothing etc. Maybe I will try it, the serviceability cannot be worse than the stuff I have to do now to maintain it..
Re:Ceramic-bearing bicycle drive shaft (2018) by nordsieck on Friday August 16, 2019 @05:17PM (#20719798)
> the serviceability cannot be worse than the stuff I have to do now to maintain it..

My understanding is that you can't maintain the hub shifter at all. It's sealed so it's generally pretty low maintenance, but if/when it eventually breaks you have to send it to the factory for repair.

Re:Ceramic-bearing bicycle drive shaft (2018) by romwell on Friday August 16, 2019 @09:16PM (#20721272)
In my many years of having bikes with internal gear hubs, some new and some decades old, I've never had a single with them.

The internal gear hubs have been perfected before derailers even became a thing; it's a very mature tech.

You can[1] do some maintenance on them. I don't have any experience with that, as all my internally-hubbed bikes were stolen long before such a point :-) :-(

[1]https://www.sheldonbrown.com/internal-gears.html

Re:Ceramic-bearing bicycle drive shaft (2018) by parsimo2010 on Friday August 16, 2019 @11:46AM (#20716328)
It's a good tradeoff in commuter purposes. It's not a good tradeoff for racing, which is where most tech is developed.

One big tradeoff you missed is efficiency. The belt drive is efficient, but internally geared hubs are currently less efficient than traditional derailleur setups. Losing watts to drivetrain loss is a major reason that internal hubs are not as popular with human powered bikes. The durability and maintenance need to be WAY better to get someone to switch over.

Re:Ceramic-bearing bicycle drive shaft (2018) by rconti on Friday August 16, 2019 @12:37PM (#20716901)
It's interesting, for sure. I've now commuted on 2 belt-drive systems. I wanted to love it. I'm settling more solidly for "mostly like".

I bought a Ghost brand bike at REI (they're a German brand, but REI is the exclusive US distributor). The model is an "Urban" of some sort, can't remember which. It has an 8 speed Shimano Alfine internally geared hub. I really wanted a Spot Acme (made in Colorado) that was absolutely gorgeous, 11 speed hub, Gates Carbon drive, brooks leather saddle, etc. But that $2k+, and the Ghost was on sale from 1300ish to $850 if I recall correctly. It didn't have a dyanamo so I bought a Shutter Precision hub and had a local bike shop build up a wheel with a dynamo so I could run lights.

The Ghost came with a Continental belt drive instead of the Gates. Instead of having the center groove of the Gates, the continental just... stays in place. Hopefully. The right side of the crank had a flange, and the left side of the hub gear had a flange, but the belt could technically fall off the 'other' side of either one. And it did, occasionally.

Belt tension is regulated by how "tight" you make it by adjusting the rear wheel in place. The Ghost frame has angled dropouts sorta like a normal road bike (not horizontal dropouts like a motorcycle or like the Spot bikes I saw). It's a COLOSSAL pain in the ass for the average person to hold a heavy geared hub wheel in place with one hand, thread the nuts on with your second hand, use a wrench to tighten the nuts with your third hand, and deal with belt tension with your 4th hand. Not to mention keeping the wheel straight. And if you don't get the tension right (how many lbs of tension for a 1 inch drop, again?) the belt will fall off. Repeatedly.

Another problem is that you need to unhook the shifter to remove the wheel. It's not that hard, but when you're a novice to these bikes, it's tricky because some models recommend you shift to the lowest gear; others to the highest. You need some needle-nosed pliers and some finagling to get the cable out.

A problem specific to the Ghost was that the rear disc brake rotor ran into the caliper as you tried to slide the wheel out. So you ALSO have to unbolt the caliper to remove the rear wheel. Overall, it's a vastly bigger pain in the ass to remove the wheel on that bike than on a "normal" bike. God help you if you have a flat on the side of the road. I went through a bunch of different tube/tire combinations before I ended up with slime tubes, which i now HATE because the valve stem gets gummed up and leaks constantly, but I've spent a year or more dealing with it (adding air every week or so) because I'm too lazy to go through the hassle of removing the rear wheel to take out those godawful leaky slime tubes. (but at least I found a tire that's great and puncture-proof!)

Anyway, back to the drive belt. After owning the bike for roughly 5 months and 1000 miles, while trying to cross a busy street, the belt snapped. I tried to source a replacement, but couldn't. I took the biek back to REI, where it sat for the better part of a month while they tried to find parts.

To their credit, Ghost had discontinued use of the Continental system in favor of Gates, and as a goodwill gesture, they replaced the entire drive system of my bike with the Gates drive system.

Knock on wood, the Gates system has been perfect, doesn't squeak like the continental system does, apparently isn't as picky about belt tension, won't slide off (because of the center groove).

The shifting is less than perfect but I like the fact that geared hubs can shift in reverse, so you can downshift at a stoplight while waiting for a green. The spacing between the gears is a bit uneven, but I think it's a pretty good low-maintenance solution for a commuter bike.

But it's not perfect.