Singlespeed & Fixed Gear - Belt drive

I'm quite sure this has been done before so would we like to have another argument about it?
**pulls pin, tosses handgrenade, ducks behind sandbags**

Belt drives for bikes. Are they a viable option for fixed gear riders?

The article that triggered this being Trek's latest bulletin (http://hosted.ap.org/dynamic/stories/C/CHAINLESS_BICYCLES?SITE=TNMEM&SECTION=HOME&TEMPLATE=DEFAULT)


Nov 18, 2:38 PM EST

Trek introduces chainless bicycles

By MICHAEL FELBERBAUM
AP Business Writer
AP Photo
AP Photo/Steve Helber

Ditch the Chain, a New Type of Bicycle Is Here

RICHMOND, Va. (AP) -- Pedalers of the world, unite! You have nothing to lose but your chains.

If you've ever been riding down the street and had your pants cuff ripped asunder, there may be a revolution at hand.

Trek Bicycle is part of a movement to bury the finger-pinching, pants-munching, rust-prone sprocket and chain, and usher in an era of belt-driven bikes that might have the inventors of the self-propelled transportation Schwinning in their graves.

Wisconsin-based Trek is introducing two models this holiday season that are chainless, instead using technology most often found in things like motorcycles and snowmobiles. While some smaller custom bike makers have used them before, Trek is the first to use the technology for mass-produced bicycles.

The nation's largest domestic bike manufacturer is hoping to capitalize on a new group of urban pedal-pushers who are trading their cars for a more low-tech way to get around because of gas prices as well as health and environmental concerns.

The U.S. bicycle industry was a $5.4 billion industry in 2007, including the retail value of bicycles, related parts, and accessories through all channels of distribution, according to research funded by the National Sporting Goods Association. More than 43 million Americans age 7 and older were estimated to have ridden a bike six times or more in 2005, the industry group said.

"People are really finding bicycles to be a very simple solution to some very complex problems that they face every day," said Eric Bjorling, Trek's lifestyle brand manager. "Anything we can do in our design to really help them and help them live that lifestyle is probably better for both the consumers and us."

Bjorling said the new belts are a low-maintenance solution to a chain, which has roughly 3,000 parts including all the links and connectors.

Aside from the whisper-quiet ride, the lighter and longer-lasting carbon-fiber composite belts won't rust, can't be cut, won't stretch or slip and won't leave grease marks around your ankles. A guard over the belt-drive and the construction of the system makes getting your pants stuck an unlikely scenario, Bjorling said.

One version of the chainless bike, called the District ($930), is a single-speed, complete with a silver body, orange accents and brown leather seat and handles. The other, called the Soho ($990), is an eight-speed bike that uses an internal hub to adjust the speed rather than gears.

Bicycles have come a long way from the "boneshakers back in the 19th century," said Orin Starn, a professor at Duke University who teaches a course on the anthropology of sports. Some companies have used direct drive or drive shaft bikes that provide some of the same benefits as Trek's chainless bikes, but those models have yet to replace the age-old chain.

"Certainly for the last 40 or 50 years we have this iconic image of the traditional bicycle that includes the chain," Starn said. "We've seen this evolution in different styles and stuff, but the chain has been a cultural constant."

Bjorling admits chain-driven bikes are still efficient, but said an urban rider won't have to worry about greasing or cleaning the chain. The belt can be cleaned with a normal cleaning agent and rag, and the bike sprocket is designed to push through any snow, dirt or grime. And one belt will typically last three years - the life span of three chains.

How riders will take to the new bikes remains to be seen, since they are not out for sale yet. The District model will go on sale in December, followed the next month by the Soho. There may be those in the biking community that may take issue with swapping bike chains with newer technology.

"Bike purists are going to take a look at it and say 'oh, you know it's another option to a chain,'" Bjorling said. "Are we going to see a ton of people switching from a chain to a belt drive? I think in some urban environments yes, but it's definitely not the coffin that's gonna bury the chain."

Over the years there have been many changes in the bike industry, specifically materials that have made products lighter and stronger, said David Oakley, a manager at Agee's Bicycles, which has been in business in Richmond since 1910.

While some may question the chainless bikes, Oakley pointed to the initial skepticism, and eventual success, of mountain bikes.

"We all know that putting gears on a beach cruiser to be able to ride back up the hill turned out to be a pretty good thing," Oakley joked of the bike industry's most popular segment.

Oakley said there's a general excitement behind the new technology, but cautioned that the notion may not ring everyone's bell.

"From a maintenance standpoint, it's huge," he said. "If this really, completely takes off, the lubricant industry is probably not going to be excited."

Viable? Yes. Desirable? In my opinion, no.

My fixie is already quiet as hell. And I have no desire to SAW THROUGH MY FRAME to put on a belt.

yeah, how do they get the belt on there?

yeah, how do they get the belt on there?

I am not sure how Trek does it on their stock models. I am sure I could find the info if I looked. But I am lazy. If they are smart, then they put on the belt before they weld the frame.

If it isn't stock though, yes, you have to saw THROUGH your chain stay to get it on.

I am not sure how Trek does it on their stock models... If they are smart, then they put on the belt before they weld the frame.


Lol.

yeah, how do they get the belt on there?

the whole dropout is removable apparently so it IS possible to put the belt there on those specific frames. i doubt the pros will warrant people suddenly modifying their current frames for a belt drivetrain.

Lol.

I Googled to see why this was so funny, and I see that the chain stays aren't welded at all, in fact, not connected at all.

IMO it makes an already undesirable bike even less desirable.

At least the colors are sexy?

Here's one...

Guess I just don't see the appeal. Not against it intrinsically, but I don't see the value of upgrading a bike to use a belt drive when a chain works great already.

I'd forgotten about fitting the stupid thing, it was looking like a good move until then (cost aside of course).

Richard

I'd forgotten about fitting the stupid thing, it was looking like a good move until then (cost aside of course).

Richard

I am not sure why fitting would be a huge problem. You already need a specialized cog and crankset ... so I am sure the fitting of the belt comes in a variety of sizes to fit this, and however far they are distanced. Not as easy as taking a link from a chain, but hell, you are already doing a lot of work for the upgrade, this seems minimal by comparison.

I am not sure why fitting would be a huge problem. You already need a specialized cog and crankset ... so I am sure the fitting of the belt comes in a variety of sizes to fit this, and however far they are distanced. Not as easy as taking a link from a chain, but hell, you are already doing a lot of work for the upgrade, this seems minimal by comparison.

Besides actual size, what about how to get it on to the bike? (Some people say fitting to mean installation.) Of course as mentioned, you cannot convert any existing bicycle from chain to belt, you MUST have the frame that has seperated chainstays, as the belts do not come apart like chains do.

Besides actual size, what about how to get it on to the bike? (Some people say fitting to mean installation.) Of course as mentioned, you cannot convert any existing bicycle from chain to belt, you MUST have the frame that has seperated chainstays, as the belts do not come apart like chains do.

From what I've read when belt drives were first being popularized, you can retrofit a bike with a belt drive ... but you have to saw a gap in your chain stay and refill after the belt has been installed.

My understanding is that advocates of belt drives say it is better not because of efficiency but more because of the low maintenance associated with them. But sawing through your frame every 3 years (the expected lifespan of a belt) and re-welding ... imo ... is WAY harder than cleaning and re-greasing a chain a few times a year, and replacing a chain takes all of 10 minutes. I've never done any welding, but I am gonna guess that takes (EDIT: typo) significantly longer.

Of course, on the Trek, the chain stays aren't welded to the seat stays, so it isn't as much of a problem. Still though, I don't see what this bike has to offer over my current bike, which cost about a third of a Trek District.

The pic's I saw show a removable section of the seat stay just above the drop-out. Not a hole or something that needs to be welded. Just a few bolts to remove. That part of the bike sees mostly compression anyway, so it is not a huge deal to put some sort of coupler in there.

The pic's I saw show a removable section of the seat stay just above the drop-out. Not a hole or something that needs to be welded. Just a few bolts to remove. That part of the bike sees mostly compression anyway, so it is not a huge deal to put some sort of coupler in there.

That's on a stock Trek District. I was referring to retrofitting bikes with belt drives.

That's on a stock Trek District. I was referring to retrofitting bikes with belt drives.

WHY would you do that?

WHY would you do that?

Uh, that's what I've been saying all along.

In response to the article, which stated:

"Bike purists are going to take a look at it and say 'oh, you know it's another option to a chain,'" Bjorling said. "Are we going to see a ton of people switching from a chain to a belt drive? I think in some urban environments yes, but it's definitely not the coffin that's gonna bury the chain."

Like I said before, I don't think in any urban environments people will want to upgrade their existing bike to use this belt drive, contrary to what the article states. It seems like a waste.

For some reason I can't quite comprehend how the belt doesn't stretch with use or from environmental factors. Is there a way to adjust tension or something?

What are the belts made of are they carbon?
I like the belt idea, why not?

I believe they are made of "carbon-fiber composite" according to the article. Apparently it does not stretch much.

I assume the problem of tension is solved by having a variety of belt sizes.

Anyhow, I think the point of this drive system is to use a bike specially designed for it.

Obviously it would be on the difficult side to upgrade a bike to use a belt drive ... and for this reason I think belt drive systems are a bad idea ... I am fine with owning one of those Trek Districts ... but on any other track frame it seems dubious at best.

Uh, that's what I've been saying all along.

In response to the article, which stated:

"Bike purists are going to take a look at it and say 'oh, you know it's another option to a chain,'" Bjorling said. "Are we going to see a ton of people switching from a chain to a belt drive? I think in some urban environments yes, but it's definitely not the coffin that's gonna bury the chain."

Like I said before, I don't think in any urban environments people will want to upgrade their existing bike to use this belt drive, contrary to what the article states. It seems like a waste.

I think by "switching" he means when they choose a new bike. I get the impression that there are riders who get new bikes pretty often instead of keeping the old one going. From a bike manufacturer's point of view, those are the only people that count.

I think by "switching" he means when they choose a new bike. I get the impression that there are riders who get new bikes pretty often instead of keeping the old one going. From a bike manufacturer's point of view, those are the only people that count.

I dunno. But I did read articles in the past about people upgrading frames to use this drive train, and I just thought it was a bad idea.

I don't think I would get a District either. I like the look of them (weirdly enough) but it all seems so proprietary. Not that that is always a bad thing, but still, seems like a headache.

For some reason I can't quite comprehend how the belt doesn't stretch with use or from environmental factors. Is there a way to adjust tension or something?

Automotive timing belts look very similar - if they stretched at all then your car doesn't work very well, so I would say belt technology is definitely good enough for bicycles.

And about that "saw your chainstays from your seatstays comment above" I am really surprised that there is even one person that will actually do that. Scary.

Automotive timing belts look very similar - if they stretched at all then your car doesn't work very well, so I would say belt technology is definitely good enough for bicycles.

And about that "saw your chainstays from your seatstays comment above" I am really surprised that there is even one person that will actually do that. Scary.

If someone really wanted to upgrade their ride to have a belt drive, they would have little choice.

I agree, it's crazy, and I have no idea why anyone would do this.

To me, the chain is a more elegant solution. A frame built to accommodate a belt drive, to me, seems a more cluttered solution.

Automotive timing belts look very similar - if they stretched at all then your car doesn't work very well, so I would say belt technology is definitely good enough for bicycles.

And about that "saw your chainstays from your seatstays comment above" I am really surprised that there is even one person that will actually do that. Scary.

timing belts and other automotive belt DO stretch, and have tensioners to compensate. so to make up for the stretch in these belts, if the are made the same materials, some kind of tensioner would be needed. and those tend to not work that well with a fixed gear. could be viable for a singlespeed, but not a fixed gear.
of course, all of the above is invalid if the belts don't stretch that much, you could just adjust your wheel in the dropouts:thumb:

timing belts and other automotive belt DO stretch, and have tensioners to compensate. so to make up for the stretch in these belts, if the are made the same materials, some kind of tensioner would be needed. and those tend to not work that well with a fixed gear. could be viable for a singlespeed, but not a fixed gear.
of course, all of the above is invalid if the belts don't stretch that much, you could just adjust your wheel in the dropouts:thumb:

I feel like the kind of RPM a bike drive belt is going to see is going to be a lot less than a timing belt on a car engine.

Considering the mild loads on a belt, I think they could certainly develop a belt which can be removed. There are many belts in industrial use (conveyors etc.) which are not endless and which are joined together in one way or another. Those belts could also come in incremental sizes.

To devil: upgrading to a bike manufacturer means that someone buys a NEW bike to replace the old, not that they modify their existing one. Once a bike is sold, it is dead to them.

I'm on the "Belt drives are the solution to a problem that doesn't exist" bandwagon.

My chain is quiet, effecient, and when I need a new one, I can stop by my local Wal-Mart [even if it's 8:00PM on Christams Eve] and buy a new one that I know will fit for about $5. Belts on the other hand would need to be ordered from the dealer at whatever price they want to charge, [add a few days for shipping too] in a specific size, to be used with a custom frame. If I wanted to change gear ratios- good luck. New cogs/chainwheels would also be a dealer item so they can charge whatever they want then I have to hope the new belt I ordered will be the right size.

I see no meaningful advantage and plenty of shortcomings. I don't think belt drives will ever be more than a niche product used on a few specialty bikes.

Considering the mild loads on a belt, I think they could certainly develop a belt which can be removed. There are many belts in industrial use (conveyors etc.) which are not endless and which are joined together in one way or another. Those belts could also come in incremental sizes.

To devil: upgrading to a bike manufacturer means that someone buys a NEW bike to replace the old, not that they modify their existing one. Once a bike is sold, it is dead to them.

Actually I've read a lot of stuff about people hacking their frames up to get the belt drive on.

Of course the manufacturer of this belt drive is going to say anything to get people to buy their new delt drive, and the bike that uses it.

I'm on the "Belt drives are the solution to a problem that doesn't exist" bandwagon.

...

Belts on the other hand would need to be ordered from the dealer at whatever price they want to charge, [add a few days for shipping too] in a specific size, to be used with a custom frame. If I wanted to change gear ratios- good luck. New cogs/chainwheels would also be a dealer item so they can charge whatever they want then I have to hope the new belt I ordered will be the right size.

I see no meaningful advantage and plenty of shortcomings. I don't think belt drives will ever be more than a niche product used on a few specialty bikes.

Bike manufacturers would love to have you come in every couple of years to replace the belt and find that to have a new one fitted is half the cost of the bike - so you just buy a new bike.

Bike manufacturers would love to have you come in every couple of years to replace the belt and find that to have a new one fitted is half the cost of the bike - so you just buy a new bike.

+1 ... I am by no means against progress. So if there is a niche for belt drives, I say, more power to them. I am just skeptical that it is going to kill the chain drive. There are too many reasons chain drives are as good f not better.

Actually I've read a lot of stuff about people hacking their frames up to get the belt drive on.


links, plz.

links, plz.

Honestly I don't remember where I read this.

I realize that this is a singlespeed forum but IMO the biggest reason this will be a niche market is that it cannot be used with a derailleur. Per the bike catalogs over 90% of the bikes shown have derailleur drivetrains.

The belt drive is practical for singlespeeds and gear hubs for those with no interest in changing overall ratios via sprocket changes but these are only a small part of overall bike sales. Many people want to be able to customize gearing range for their local riding conditions on ANY bike, singlespeed, fixed gear, gear hub or derailleur.

IMO the more someone is truly into biking the less likely they will choose such a drivetrain. This might be popular for the casual low mileage cruiser or urban rider but not serious bicyclists.

I also wonder about the effects of dirt, mud, sand etc on both belt and drive sprockets. Harleys have used belt drives for years but I have not seen them used on any dual purpose or off road motorcycles which are subject to such conditions.

If someone really wanted to upgrade their ride to have a belt drive, they would have little choice.

I agree, it's crazy, and I have no idea why anyone would do this.

To me, the chain is a more elegant solution. A frame built to accommodate a belt drive, to me, seems a more cluttered solution.

Please stop filling this topic with information you've made up or "read somewhere". The same company that sells the belt drive systems sells SPECIFIC dropouts that must be brazed into existing or new frames.

Meaning...

If you're converting a old frame into a single speed belt drive, you must find a local framebuilder to cut your dropouts off and braze new ones in, assuming your old frame is made of steel or the framebuilder knows how to work with Aluminum.
Cutting the seatstay has been a rumor tossed around the bike community since belt drives were first introduced.



IMO the more someone is truly into biking the less likely they will choose such a drivetrain. This might be popular for the casual low mileage cruiser or urban rider but not serious bicyclists.

I also wonder about the effects of dirt, mud, sand etc on both belt and drive sprockets. Harleys have used belt drives for years but I have not seen them used on any dual purpose or off road motorcycles which are subject to such conditions.

Where are these "serious bicyclists"? I'd like to speak to them about how into biking they really are.
I would imagine that the wear on a belt drive would be significantly less then a traditional chain driven system because there is no lubricant, thus the dirt, mud, sand etc would not have much to stick to.

As was discussed in the 'commuting' sub forum....all it takes is a vandal with a sharp knife and you are screwed.

I realize that this is a singlespeed forum but IMO the biggest reason this will be a niche market is that it cannot be used with a derailleur. Per the bike catalogs over 90% of the bikes shown have derailleur drivetrains.

The argument against that is that most people using single speed bikes are using 1/8 chains which are not used by the geared set. The 'size of the market' argument isn't really relevant from that perspective. Where it gains relevance is the consideration that not all single speed bikes will be using belts, even if the entire industry changed to them now on new bikes.

Now, swiping this post from the commuter forum:

Delta got around this by changing the triangle on their CDrive bike:

http://www.deltacycle.com/images/cdbig2.jpg

http://www.deltacycle.com/images/cdbig4.jpg

No need to break the frame to fit the belt here ... though once again, you need a specially designed frame.

I reckon belts have a future. The cleaner, smoother, longer lasting, less maintenance arguments all hold up. The problem would be the cost. BUT, if you were given a choice between two new bikes, both identical except that one was belt and one chain, and the price of replacement belt bits was reasonable, the belt drive is a good choice.

Surley? They seem to specialise in coming up with frames that no-one else wants to make and then making them viable.

People laughed at Harley when they introduced belt drives, and don't laugh now. Mind you, one of the attractions was the way the belt smoothed out the dreadful power delivery on a Harley (yes, I have ridden the things and yes, if I had the money, I'd own one, I'm just not blind to their limitations).

Richard

As was discussed in the 'commuting' sub forum....all it takes is a vandal with a sharp knife and you are screwed.

And, unlike chains, the space and weight of a spare belt is trivial. The Trek District uses an allen-head bolt for dropout removal, and it's probably save to assume that the size is what's found on most multi-tools.

I don't know about you, but I'd rather have to spend five minutes on my knees removing a dropout and installing a clean belt than removing an old, dirty chain and installing a new one, leaving your hand full of that wonderful factory-installed lube.

Shown here http://carbondrivesystems.com/installation.php is a manufacturer's walkthrough for putting the belt on. It shows a relatively elegant way for getting through the frame too, if you've got a track fork end and it's steel (strength), etc. etc. etc.
That said, despite the "neat-o" factor, I'm sure not gonna chop my frame. Or get a new drive train. As someone said before, it's a solution to a problem that doesn't exist and seems to actually create even more.

Shown here http://carbondrivesystems.com/installation.php is a manufacturer's walkthrough for putting the belt on. It shows a relatively elegant way for getting through the frame too, if you've got a track fork end and it's steel (strength), etc. etc. etc.
That said, despite the "neat-o" factor, I'm sure not gonna chop my frame. Or get a new drive train. As someone said before, it's a solution to a problem that doesn't exist and seems to actually create even more.

I'm guessing you have to cut a bit out of your track end and then bolt something else in place - is that right? If so, is that smart? In my ignorance, I would have thought that the track end was something you wanted as strong as practical and unity is always better than 'bolted together'.

Richard

I would have thought that the track end was something you wanted as strong as practical and unity is always better than 'bolted together'.

Richard

Yeah, no kidding. I'd be a bit nervous but I guess if you really like surprises... . One of the nice things about the track end in particular is that it can handle an amazing amount of torque - at least in its original configuration.

As was discussed in the 'commuting' sub forum....all it takes is a vandal with a sharp knife and you are screwed.
What the hell is that supposed to mean? Slashing tires would do far more harm than cutting the drive belt. And all bikes have tires.

The belts are kevlar and carbon fiber READ very light and extremly strong , NO strech or backlash as in any chain drive system (there is always "some" slop in each link) and smooth as silk if designed properly.It will have zero slop on any reversal and instant responce to input. Does that sound like something a track rider on a fixed might want or a velo drome rider maybe. Definetly for cross riders. I don't think the average bike rider would ever be able to use the fraction of a second it may gain, but someone will. We started to use them alot in AC/DC servo drive systems because they smooth out the harmonicsand last longer than the chain drives. Hey guys its all science LOL.

What the hell is that supposed to mean? Slashing tires would do far more harm than cutting the drive belt. And all bikes have tires.

i actually go around to bikes taking just on pin out of the chain... then i use GPS tracking to find out where the bike went and i T bag them when they fall off their bike...

or gorilla mask... its a close call...

Please stop filling this topic with information you've made up or "read somewhere". The same company that sells the belt drive systems sells SPECIFIC dropouts that must be brazed into existing or new frames.

The point was about the practicality of it, not the methods used.

Which is harder? Replacing a chain or brazing on new dropouts?

HMMM ... I wonder.

Like I said before, for me, personally, replacing a chain or applying new lubricant is not nearly as much of a hassle as the author of this article seems to suggest. Equally over exaggerated is how loud chain drives are.