Bicycle Mechanics - Belt drive versus fully enclosed chain - pros and cons?

I was mulling over a future city commute bike project.

In Portland, during the winter my commute is in rain or at least wet roads practically 100% of the time. Drivetrains get gunky and require pretty frequent maintenance.

So I was thinking about either a fully enclosed chain, or a belt drive.

What do you consider the pros and cons of these options?

These would go with an IGH, drop bars, disc brakes, wide tires (maybe 650b), the fullest-coverage fenders with long flaps, generator hub and lots of lighting, and possibly a small "bikini" type fairing.

belt is perfect for this, but it requires a frame with a rear triangle that can be 'opened' so you can install/replace the belt. trek has one where the rear 'dropout' can be seperated, specialized has a joint up by the brake bridge on the seat stay. this pretty much limits you to a factory bike.

Even a fully-enclosed chain drive system is still going to get water and crud splashed into it and the chain will still need lube so will not be totally maintenance free. It will also be an extra hassle when fixing a flat.

The belt drive is nice but the frame concerns noted above do exist. Also if you decide to change the chain wheel or cog to change the IGH range you will need a belt-specific one as well as a new, correct-length belt, you cannot add or subtract links like with a chain.

Never used them, but I would forget the rubber belt. They have poor cog selection and torque. I doubt they like muddy cogs either. What LBS would ever stock that stuff anyway ?
I used Sturmey Archer 90mm drum brake hubs this year, dyno and oil filled RD5w. Flawless performance with zero fiddling with the non-adjustment brakes, not so with discs. For best results use long cranks and yes to a full chaincase.

For either set up (chain or belt) consider flat proofing the rear tire best possible. I've worked on enough full chain guarded bikes (usually an internal geared hub) and a few belts drives. All I can say is they both would be a pain out on the road, in the cold and rain, if you got a flat. Andy.

These would go with an IGH, drop bars, disc brakes, wide tires (maybe 650b), the fullest-coverage fenders with long flaps, generator hub and lots of lighting, and possibly a small "bikini" type fairing.

I was out riding today. Beautiful day , but lots of icy spots to avoid. Made it back unscathed.

I think you're describing something like Rob English's Winter bike: http://www.englishcycles.com/custombikes/special-winter-bike-project/ . It's made it through 3 Oregon winters and 7000 miles of use with essentially zero maintenance.

For either set up (chain or belt) consider flat proofing the rear tire best possible. I've worked on enough full chain guarded bikes (usually an internal geared hub) and a few belts drives. All I can say is they both would be a pain out on the road, in the cold and rain, if you got a flat. Andy.

A belt drive with Open forward horizontal (traditional road type) or vertical dropouts with a chain tensioner system, like an eccentric BB, or moveable dropouts are easy to work with on belt drive because there's no need to remove the belt.

If you plan this with rear opening (track) dropouts make sure there's room between the rear sprocket and dropout for the belt. You also need enough forward room in the slot to move the wheel up and slacken the belt enough to come off the sprocket.

An enclosed chain, at least up to the rear wheel, if not fully, will stay fairly clean and lubed in rough weather so that's a viable choice. I've not enough experience to comment on how grit and dirt affects belt wear, but don't assume belts are magically shielded from dirty, gritty road spray.

Years ago all weather riders with single speeds or IGH used split plastic tubing of the kind used to keep wires in place wound fully around the chain. This worked amazingly well, though it would eventually get worn at the slot. I'm a bit surprised that I don't see this stuff anymore.

Half of a solution:
http://www.universalcycles.com/shopping/product_details.php?id=56077&category=3920

http://www.universalcycles.com/images//products/medium/56077.jpg

There's also the Hebie Chainglider:
http://www.bikeradar.com/gear/category/accessories/product/review-hebie-chainglider-33772

http://cdn.mos.bikeradar.com/images/bikes-and-gear/components/chain/1230049824698-t2cbi1ggbbt9-670-75.jpg

but I don't know who has these in the U.S.

I was out riding today. Beautiful day , but lots of icy spots to avoid. Made it back unscathed.

I think you're describing something like Rob English's Winter bike: http://www.englishcycles.com/custombikes/special-winter-bike-project/ . It's made it through 3 Oregon winters and 7000 miles of use with essentially zero maintenance.

Good for you! I was in bed with a hangover until 11 AM.

It is getting cold enough that I'm having to remember that, hey, ice is possible now. The other day I was hustling from west bound NE Couch onto the Burnside Bridge. You know the "S curve" there. I was diving into the first S when I realized, uh-oh, the road surface looks different this morning. Too late to slow down but I took the curve as wide as I could. Wasn't icy as it turns out, but at 5 AM it could easily have been.

When you say fully enclosed chain, do you mean one of the chain cases with the oil bath? That would be cool.

The bike you described sounds perfect. I would probably forget the chain case and just run the cheapest 1/8" chain I could find, and run it until it skipped. Which would probably be a while on an IGH. That would mean replacing the cog and possibly the chainring too, but it might be cheaper/easier than dealing with proper maintenance, a chain case or belt drive.

I was out riding today. Beautiful day , but lots of icy spots to avoid. Made it back unscathed.

I think you're describing something like Rob English's Winter bike: http://www.englishcycles.com/custombikes/special-winter-bike-project/ . It's made it through 3 Oregon winters and 7000 miles of use with essentially zero maintenance.I went through a Gates belt in 1300 miles on our tandem. Actually, not the belt - the rings, being aluminum, simply wore away from grit. Didn't help the belt any, either. I washed the bike regularly, too. I went back to chain. I do think a Center Track belt would last longer, but not any 7000 miles. English obviously doesn't count swapping out not just the belt, but also the rings, as maintenance. He can't have changed belts without changing rings, and his rings are more expensive than ordinary chainrings. Tires? I never wear out a tire, no, but they get cut badly enough to be unrideable in between 50 and 1000 miles in the winter around here. Tubes? He never flats? I call BS on this. Not to say that what he suggests is a bad idea. But saying that there's not going to be maintenance on a bike that's ridden constantly in a PNW winter is simply not correct.

... but I don't know who has these in the U.S.
Aaron's in Seattle is retailing Hebie chaingliders..


I thought belt drives would be good , fully enclosed.. the grit wearing the cogwheels
is one reason..

Having it anonimous is annother [belt outside is a show off, since recent and pricy]

Enclosed chains unless in an Oil bath, tend to be ignored too much..

Now,a Chain kept clean AND running in a oil bath , like the timing chain
running Overhead cam engines.. last a very long time ..100k + miles

but on a bike you have rear punctures.. to remove the wheel is
requiring the chain case to be opened, and oil to likely spill..

How about a shaft drive system? Totally enclosed and the gears are in a lubricant bath. Here is an example which has many of the features you have specified; http://shop.dynamicbicycles.com/Tempo-8-Tempo-8.htm
Drop bars and a dyno hub/lights could be easily added. http://www.ecovelo.info/2008/11/12/alfine-shifter-with-drop-bars/
A local park has a similar model for rent and the concessionaire has vouched for their reliability. Here's the drive manufacturer's page: http://www.sussex.com.tw/index.html

How about a shaft drive system? Totally enclosed and the gears are in a lubricant bath. Here is an example which has many of the features you have specified; http://shop.dynamicbicycles.com/Tempo-8-Tempo-8.htm
I had a chance to ride one of those last summer. Even on a level park road, the drag was obvious and it felt like riding on badly underinflated tires. With their obvious strength and low maintainence, shaft drives would have taken over the bicycle world if their efficiency wasn't so dreadfully low.

I'd go with the enclosed chain system at the moment. Belt drives require too many components that are manufacturer-specific so I'd wait until it's clear there's a uniform design that'll be around for a long time and have multiple sources.

I'm also a little skeptical about the reluctance of Gates to release detailed efficiency test results.

Spot bikes makes several Gates equipped models. Acme (Alfine11) and Ajax (Alfine8). Good specs and good reviews.

Recent article (02 Jan '13) measuring chain vs belt efficiency: http://www.bikeradar.com/road/news/article/chain-or-belt-drive-which-is-faster-36074/

Super interesting link, thank you.

If preloading was not a factor of either drive system, when the performance of the belt is compared to the performance of the chain, with all test parameters being equal, the CDS belt actually becomes more efficient than the chain at given span tensions above 21.90 lbs/span (43.80 lbs total span tension).

BUT

the increasing preload needed with increasing rider output will always cause a CDS to perform less efficiently than a chain drive system at similar rider output wattage.

SO

In theory, if a belt drive system was able to operate in a similar tension manner to a chain drive system, i.e., with low or no preloading requirements, the belt drive system would theoretically be more efficient than a chain drive at all rider outputs greater than 208 watts.

I guess we can watch and see how belt technology develops.

While they are at it, I wonder if the cog can be moved to the outside of the dropout, so that the belt can be replaced without requiring an opening gate in the stays.

Let's suppose I was going to look for a used bike to convert into this dream wet weather commuter. I would want disc brakes, clearance and mounting points for fenders and wide tires. The ability to use an internal gear hub - I'm thinking horizontal drops since a chain tensioner won't work with a full chaincase. Road bike or old (pre-suspension) mountain geometry with a fairly low head tube so I can get down in the drops. I'd add the drivetrain, keep the disc brakes, use Versa brifters, build new wheels.

Any suggestions for newer bikes that would fit this bill and that I might find used or frameset-only for not too much? You know, the mythical free Surly Disc Trucker or something.

Or am I better off finding a old steel MTB frameset for $50 and having disc brake mounts welded on? I think an old MTB rigid fork would be strong enough to mount a disc?

Hmm but neither has horizontal drops.

re the old steel MTB frame, actually, you'd *braze* those brake mounts onto the stays/forks, not weld.

a /really/ old mountain bike WILL have horizontal drops, I know my 1983 Stumpjumper does.

http://www.hogranch.com/digi-2007/2007-06-18/slides/IMG_9137.JPG

Yeah but I wouldn't mangle up an '83 Stumpjumper.

anyways, its a total tank of a bike. weighs a ton. I once tried 26x1.5 slicks on it, and it was way twitchy handling, did better with heavier tires like 26x1.75's (never mind the phatt mudslingers it has on it in that pic)

I ride in Minnesota winters and I wouldn't expect good things from a chain case. The reason is, it's not going to keep out 100% of the slush, but on the the other hand, what gets in will tend to stay in. I'd expect it to accelerate the rusting of the chain, not prevent it.

It's a moot question for me, because a chain case won't work with a derailleur.

I would like to try belt drives. They have been used for a couple of round the world records.
The cogs are mostly aluminium but the 3 mounting tabs really need to made of steel for strength.

You probably need to keep a small stock of belts and cogs.

The best tensioning system is probably a split triangle at the dropout with sliding vertical dropouts.
You can get widgets to split the frame mid seatstay and you can use an EBB but that all ads weight.

On my own Alfine system I have changed to 1/8 chain. I use 1/8 Sturmey Archer rear sprockets but they are a bit thick so I need to sand them down for about 2 hrs to get the tabs to the correct thickness for the snap ring to work.

While they are at it, I wonder if the cog can be moved to the outside of the dropout, so that the belt can be replaced without requiring an opening gate in the stays.

English built a bike like that: http://www.englishcycles.com/custombikes/project-right/

Have you heard of a Civia Bryant? http://civiacycles.com/bikes/bryant/ If you can find a used one it would get you most of the way there. What about a rigid 29er frame? There are quit a few with eccentric bottom brackets and disk tabs. I always thought my Raleigh xxix would be interesting with an IGH.

belt is perfect for this, but it requires a frame with a rear triangle that can be 'opened' so you can install/replace the belt.

And there's that 15-20 year old MTB design where the right chain stay attached 1/3 up the seat tube. The original intention - if I remember the marketing correctly - was to eliminate chain slap. But it'd be a good candidate for a belt conversion. I'd been watching one locked and abandoned to a street post, but the need wasn't big enough to merit the potential embarrassment of trying to force the wire w/o legal right.

Dahon freedrive provides good chain protection. Like belts, it's not detailer friendly.

http://youtu.be/x8kIsY1yMoA

I've been riding a belt drive bike for about 8 months now and can honestly say that I don't see any reason NOT to switch to a belt drive. Especially for less than ideal riding conditions. Short and long term, I think it's a better option than an enclosed chain.

I built up a Raleigh Twin Six as a 1x8 CX with the Gates Center Track, an Alfine 8 hub, and JTech bar-end shifter. I've got between 1500-2000 miles on it in all but the wettest and sloppiest conditions (it's pretty dry where I live). About 60% of the miles I've put on it are in the dirt. The other 40% is to and from the dirt. Last summer, I treated it like a mountain bike on the local single track, and last fall I was doing 2-4 laps on the local cross course almost every day for two months. I've put road tyres on it and done 35-45 mile training rides, and I've done 25-35 mile gravel grinding rides. I've ridden the cross course in the dry, snow, and light mud. I think I put it through some pretty rigorous paces in it's first year. As soon as the odometer hit 1000 miles, I took off the computer and quit keeping track because everything is working so well.

Pro: Silent, dead silent. After proper setup, even the stealthiest of bike ninjas would be envious. My well maintained road bike sounds like a dirty, rusty, sloppy, grunge magnet by comparison.
Pro: Clean. No more grease tats on the calves. No need for a rubber band on the pant leg. It's also clean and pleasing aesthetically.
Pro: Not quite zero maintainence, but a lot less than a chain driven bike riden under the same conditions. A quick spritz with the garden hose is all I've had to do. I don't even need to wipe off the excess.
Pro: Smooth. It's just ridiculous how smooth it is. Hot, cold, snow, rain, mud, dry, it is just smooth.

Con: Cost. The belt components are on the pricey side, but not outrageously so. An Alfine 11 hub and Versa brifter combination would have added significant cost to the project over my Alfine 8-JTech combination, but that would be the same for a chain driven setup.
Con: Initial setup is touchy. This is my first IGH bike and there was a learning curve to getting the right tension in the shift cable and belt. Someone with IGH experience might find it a little easier. It turns out that with belt tension on an IGH, less is more. It took some miles to figure that out, but once I got it dialed in, I haven't had to touch it. Still less fidgety than a derailleur.
Con: Anodized aluminum drivewheel. I ride in dry and dusty conditions and the fine grit caused the anodizing on the drivewheel to wear off. It also caused a period of unbearable drivetrain noise. To the point that I almost gave up on it and went back to a chain drive. I attribute much of this to dialing in the proper belt tension, because as soon as I eased up on the tension, I stopped seeing any wear issues on the drivewheel and the belt squeal ended completely. In wet conditions this was never a problem. The cog is naked stainless steel, so there isn't the same wear issue as the drivewheel. If Gates would sell a stainless drivewheel, it wouldn't be an issue at all....just heavy.

Any other issues that the skeptics who haven't tried it might bring up like belt stretch, wear, efficiency, and flat repair are really non-issues.

Even under heavy load, there is no perceptible belt stretch. I can feel the frame torque before I notice belt stretch. I have not experienced belt slip/skip once, and I have torqued it up pretty good. A substantial piece of debris might cause problems, but that isn't unique to a belt drive. I have experienced some gear slippage from the hub, but that seems to also have been related to belt tension, because it hasn't happened since I eased up on the belt.

It's tough to quantify effiency. It is a less effiencient machine than my road bike, no doubt, but I don't know how much of that can be attributed to the belt drive vs. the design and intent of the bike. I experience less fatigue than I would on the road bike for the same amount of time in the saddle, so there are trade offs to be considered when thinking about efficiency.

Most of the time I can patch a flat without taking off the rear wheel. For the instances where the wheel must come off, it only took a couple of tries before I could do it nearly as quickly as a QR hub. I have no hesitation when I want to swap tyres, even for just one ride.

The Alfine hub has been bulletproof since getting it dialed in and has required no maintainence. I've used it like a mountain bike so I think that's really saying something about its durability.

The only perceptable wear that I have seen on the belt is the anodizing from the chainwheel. Granted, I don't have a ton of miles on it, but I see noticably less wear on my belt than I would on a chain with similar miles and conditions. My only lingering concern is the aluminum drivewheel, but again, I don't think this is an issue since I got a handle on proper belt tesion. I expect to get the equivalent of several chains and cogsets worth of life out of my drivetrain.

http://i191.photobucket.com/albums/z137/breathegood/Bikes/IMAG0310.jpg
No problems on a snowy cross course.

http://i191.photobucket.com/albums/z137/breathegood/Bikes/IMAG0210.jpg
No problems on singletrack.

http://i191.photobucket.com/albums/z137/breathegood/Bikes/IMAG0100.jpg
No problems on the MUP with road tyres......except people can't hear me comming.

http://i191.photobucket.com/albums/z137/breathegood/Bikes/IMAG0334.jpg
No problems at the bike park.

http://i191.photobucket.com/albums/z137/breathegood/Bikes/IMAG0009.jpg
No problems on rural gravel roads.

http://i191.photobucket.com/albums/z137/breathegood/Bikes/IMAG0352.jpg
No problems on pavement.

http://i191.photobucket.com/albums/z137/breathegood/Bikes/IMAG0335.jpg
No problem!

My bike would be an excellent candidate for a belt drive - the Biria frame geometry bypasses the whole "split frame" problem - but I'm stopped by Gates's recommendation not to use it with an IGH with a coaster brake. Sigh...

My bike would be an excellent candidate for a belt drive - the Biria frame geometry bypasses the whole "split frame" problem - but I'm stopped by Gates's recommendation not to use it with an IGH with a coaster brake. Sigh...

This is speculative so read it with a grain of salt.

I suspect that Gates' no coaster brake advice is based more on legal concerns than mechanical. There's generally less chain (belt) tension when applying a brake, then when accelerating hard or climbing. As long as you're staying within the sprocket size guidelines there's no real reason that you couldn't use this with a coaster brake IGH hub.

However there is always the risk of belt failure, so be sure to also mount a caliper (or canti) brake on the front wheel, both as plan B and becuse coaster brakes are often inadequate in an emergency allowing you to skid into a crash.

if it was me, i would hand turn the crank while holding a rag on the chain for a couple of turns. then throw my (your) favorite lube on the chain and call it good. i'd do this once before each ride.

That's a great report. Thanks! The bike looks simple and purposeful.

if it was me, i would hand turn the crank while holding a rag on the chain for a couple of turns. then throw my (your) favorite lube on the chain and call it good. i'd do this once before each ride.

Yeah, but I ride the bike 2X day, every weekday, and 4-5 times on weekends, and during the winter it will be raining for all but a couple of those rides. So even a brief bit of maintenance per ride is too much.

Yeah, but I ride the bike 2X day, every weekday, and 4-5 times on weekends, and during the winter it will be raining for all but a couple of those rides. So even a brief bit of maintenance per ride is too much.

Take your bike to Velo Cult in Portland, and ask them to put some Chain-L on your chain. It's totally free (clean your chain decently & bring a beer or coffee if you wish). That should allow you to greatly increase the maintenance interval. The worst that can happen is that you like it, then you'll be out a few bucks.

This is speculative so read it with a grain of salt.

I suspect that Gates' no coaster brake advice is based more on legal concerns than mechanical. There's generally less chain (belt) tension when applying a brake, then when accelerating hard or climbing. As long as you're staying within the sprocket size guidelines there's no real reason that you couldn't use this with a coaster brake IGH hub.

However there is always the risk of belt failure, so be sure to also mount a caliper (or canti) brake on the front wheel, both as plan B and becuse coaster brakes are often inadequate in an emergency allowing you to skid into a crash.
Honestly, that's pretty much my thinking too. Already have a caliper on the front!

Take your bike to Velo Cult in Portland, and ask them to put some Chain-L on your chain. It's totally free (clean your chain decently & bring a beer or coffee if you wish). That should allow you to greatly increase the maintenance interval. The worst that can happen is that you like it, then you'll be out a few bucks.

Uhh... FB, I think Velo Cult is the one bike shop where you can't bribe the mechanic with a beer or coffee. Velo Cult has the shop on one side and a beer/coffee bar on the other. (And a mini-theatre in the basement, where my recumbent club has had its last couple meetings. They're subversives, I tell ya.).

Beer taps. Notice bike shop in the background:

http://velocult.com/wp-content/uploads/2012/05/Bar.jpg

Jeff,

Isn't that a fairly long commute for club meetings? The beer must be very good.

Jeff,

Isn't that a fairly long commute for club meetings? The beer must be very good.
Not that long a commute. Notice his sig says "other Vancouver". There is a town named Vancouver in the state of Washington right across the Columbia River from Portland.

BTW, your comment to use at least one caliper brake on a belt driven coaster brake bike should also apply to a regular chain drive coaster brake bike. A chain can break or come off it's chainring or cog, just like a belt.

Thanks FB. Velo Cult started me on Chain-L, and I use it now. About time for another bottle. It helps a lot with the actual business of keeping my chain quiet. But the driveline still looks awful with all the streaky black road schmutz. Riding in daily rain does that. I even pressure wash it every few weeks, it bugs me so much.

Not that long a commute. Notice his sig says "other Vancouver". There is a town named Vancouver in the state of Washington right across the Columbia River from Portland.

BTW, your comment to use at least one caliper brake on a belt driven coaster brake bike should also apply to a regular chain drive coaster brake bike. A chain can break or come off it's chainring or cog, just like a belt.

Ahhh! the OTHER Vancouver. Jeff's posts are always so polite and friendly that I just figured he had to be a Canadian. But I should have known because he doesn't say "eh".

Anyway, you're right that there's a danger of chain breakage and that isn't only a belt issue. However the second reason I mentioned; that rear brakes alone are inadequate for adult bikes ridden in traffic is the more important one. Chain breakage is fairly rare, and belt failure probably is roughly as rare, so you could ride for years without facing that, but you could need to stop fast to avoid a car running a stop sign or a kid running from between cars any time or any day, and only a front brake can do that for you.

Ahhh! the OTHER Vancouver. Jeff's posts are always so polite and friendly that I just figured he had to be a Canadian. But I should have known because he doesn't say "eh".


Through my wife I have relatives in the Peace River country in Alberta. I'll give you an honorary "Take off, hoser".

I grew up in Southern California and moved to the Portland/Vancouver area 16 years ago. I've been dabbling in bikes all my life. I had a career in the bicycle business that lasted about 12 years, but now I have a real job that pays enough that I can afford the parts I used to drool on. I also have a wife that facilitates my addiction. And cats, too. Life is good.

I can't be relied on for any useful advice, b/c I despise gates belts and cannot wait for them to go away permanently. (I'm guessing in, like, 5 years.) I'm certainly a bit biased. I'm posting mostly to applaud the smart fellow up above who speculated that elevated chainstay bikes (like the Nishiki alien but with horizontal drops) would be a better approach to belt-drive bikes than the current break-away dropouts/ seat stays we're seeing now. I used to push a 28"-wheeled roadster with rod brakes; i always wanted to put a belt on there b/c the bolt-on situation at the seat cluster made it possible. But then I remembered that belt-drives are rather expensive and excessively diva.

Don't run a belt with a CB; the changing tension will destroy the belt, b/c those belts are way delicate and need to be tuned with an iPhone app. I mean, I guess if you have an app that'll sync up to your coaster brake to ensure that exact tension is maintained....:lol:

Another smart fella recommended 90mm drum brakes as a better "all weather" alternative to disc brakes; I'd like to second that suggestion. Drums work great in the wet n sloppy, and are as weatherproof as anything short of a CB. I love mine. This would also solve your perceived requirement of horizontal drops with disc tabs. (But, if you must have that, look for a used surly 1x1, karate monkey, or redline monocog...)

Come to think of it, if you cannot afford a disc trucker (which has vert dropouts, btw) then you probably cannot afford belt drive and discs and all that other stuff. Which is to say, it is likely that you probably *can* afford a $500 frameset as well as the other components. If you can't, why not get an 80's mountain bike and get creative from there?

I sincerely doubt this helps, and I'm sorry, but belt drive really puts me in an incredibly sour mood.