tatfiend 

Any high mileage riders have experience with the current belt drives yet?

If so how are they holding up?

How difficult to properly tension the belt after a puncture repair?

Any problems with belt slip/jump in wet weather or while riding out of the saddle or in other high torque riding situations?

The manufacturers are pushing belt drive as an improvement over chains for SS & IGH bikes and I am wondering if there is any truth in this advertising.

fuzz2050

I admit my experience comes only from a brief test ride, and lots of hearing other people talk, but they seem to work just as well as chains do. Really, if I didn't know there was a belt in place, I wouldn't of been able to tell you. I (nor anyone I've heard of) felt no slip, no give or any indication that it wasn't a chain durring riding.

garage sale GT

One of the drawbacks would seem to be that you are flexing a rubber belt continuously. You might add more hysteresis drag to your bike than going with low pressure cruiser tires because you're flexing more rubber.

Totaled108

Are they not reinforced with nylon or other none stretchy material? The timing belt on my Volvo is under quite a bit of stress and heat. Over 50,000 miles it hardly stretches. So I imagine if these, bike belt drives are built similarly, they should hold up quite well to the stresses our legs and bike loads can throw at them.

Time will tell, but I'm sure the only problem will be some punk kids with a razors cutting belts on peoples bikes.

cs1

I'm thinking not. My Harley had a belt drive. I'm willing to bet there's not a single rider anywhere that can put as much torque on a belt as a motorcycle. Not to mention all the auto engines using belt drive. Belts have come a very long way in the last several years.

Mike T.

Google Mark Bowthorpe. No-one has more miles on a belt drive than he does. He just set the round-the-world record on a Rohlof hub belt driven.

AdamDZ

Yup. Belts may be stronger than chains. Think of the timing belts used in car and truck engines. That's some real heat and torque there compared to a bike and they survive tens of thousands of miles.

Adam

joejack951

Heat, yes. Torque, not so much. The belt is only spinning the cam(s) and maybe the waterpump. I can do those tasks by hand (though not quite as fast). Timing chains often last the life of a car while belts are typically replaced before 100,000 miles, if not much sooner. Timing belts are used for lighter weight and lower noise, not for longevity

That's not to say that a belt drive couldn't hold up on a bike. CVT transmissions use belts and so do motorcycles so a bicycle should do just fine with one assuming it was designed correctly.

well biked

Gates, a leader in automotive belts, seems to be the leader in bicycle belts. At Interbike this year, it was all the buzz. We saw a Gates belt on a Co-Motion tandem; the timing chain was actually a belt, not a chain. That seemed to make good sense.

garage sale GT

??? Maybe your Harley had ape hanger handlebars, does that mean a bicyclist can also sit completely upright and not experience any more drag?

The auto industry also uses rubber tires with heavy plies and quarter-inch-thick sidewalls; does that mean bicycle riders who buy high-tpi skinwall bike tires are wasting their money?

Contrast the ease of pushing your bike with pushing your Harley or a car to consider how a tiny bit of hysteresis could cost you maybe an m.p.h. or so on a bike.

Whether or not it comes from drive belts, there's simply a lot more drag on a motorcycle or car so another little bit doesn't defeat the concept.

You're just not dealing with that much excess horsepower on a bicycle.

2manybikes

They won't work with a typical bike frame. The belt has to go around the rear wheel stay. They are very difficult to tension properly on a normal bike rear wheel set up. They are slow. One needs a special tool to do an on the road repair. One must use a internally geared rear hub, adding even more energy loss to the drive system.

They are not new. Every year some one brings them up again. It's a terrible idea for a bicycle.

layedback1

I can probably speak to cog belts with some authority. I have worked with them for more than 40 years. As people point out these belts are use on auto and motor cycles and work just fine. Personally tho I wont buy a car with a cog belt running the cam. Chains are far superior there, and belts are expensive to change. Tension after a wheel change is not a big deal. In fact most people probably pull the wheel too tight. Over tension just wears out the bearing. In the local bike shop I pointed out that they had the belts way too tight. You could pluck them and they would vibrate. Thats too tight!.

stevetone

The same could have been said (more or less) when the derailler was first used on a bike.

Change happens.

stevetone

The same could have been said (more or less) when the derailler was first used on a bike.

Change happens.

HillRider

Change happens but not always for the better. The derailleur was an obvious, clear-cut improvement as it made multiple gears possible without a serious reduction in efficiency or increase in weight. The belt drive's only benefit is cleanliness as it doesn't require lube so it doesn't attract dirt. Otherwise I see no reason to use one.

fuzz2050

tell that to the people in the SSFG forum. Derailer systems weigh substantially more, rob the system of a lot of efficiency due to chainline issues, and require much more maintenance.

HillRider

The people on the ss/fg forum don't have the hills to climb than many of us do.

Sure a derailleur system adds complexity and weight but it also adds versatility that no ss can possibly have. As to mechanical efficiency, a clean derailleur system is 97-98% mechanically efficient so a ss/fg can't be a whole lot better.

2manybikes

Belt drives are not new or change. The same could not be said about derailleurs. They were an improvement.

well biked

First, let me say that I love lots of gears, and I have no desire to ride a single speed or fixed gear bike. That's my choice, of course.

But I will also say that you should not make assumptions about what some single speed and fixed gear riders are capable of doing on their bikes. I know people who ride some amazingly steep terrain on single speed mountain bikes, and they make their way to the top just like the rest of us, with our multitude of gearing options. They ride a different style to do this, but they get it done. I also work with folks who ride fixed gear bikes, usually set up with around 70 gear inches, over very long distances and up hills that any sane person would avoid without some low gears to help out.

I am in no way trying to argue against multiple gear drivetrains, I'm just saying that you would be amazed at what some folks can do with just one gear. I've seen it, and it never ceases to impress me. It also makes my knees ache just thinking about it.

HillRider

I wasn't making any assumptions. The fact that a few gifted individuals can do amazing things with limited equipment doesn't mean it's a reasonable choice for the majority of riders.

jack002

Climbing hills in high gears will destroy your knees, I don't care who you are, its not good for knees.

SlimAgainSoon

The belt drive's only benefit is cleanliness as it doesn't require lube so it doesn't attract dirt.

Well, that and the fact that they last forever. Also lighter, and essentially silent.

I'd like to see someone experiment with belt drive and a derailleur. Seems there is the potential for a very light drivetrain without the wear-and-tear inherent in metal-on-metal systems.

Jeff Wills

Can't compare apples and oranges- you can't run a belt in a derailleur-type system. The real comparison would be two equivalent single-speed or fixed-gear or internal-hub bikes, one with a light belt drive, the other with a well-shielded roller chain. I find it hard to believe that a belt would last longer than a chain in a full chain case.

Another issue with the Gates belt drive is that they're fixed in length. That is, your bike's design is dictated by the length of the belt: wheelbase, distance from cranks to rear wheel, drivetrain specs, etc. That locks out their utility for cargo bikes and recumbents.

phoebeisis

Just look at the motorcycle world. Where max performance or FE or weight or gearing changes or anything performance oriented is needed, you see chains. Only Harley uses belts(and a few Kawasakis the older 440 500 twins).

It is hard to beat a chain.

You can beat the grungy oil on the chain by doing without oil(SS or Teflon chain ) but you will have to replace it more frequently.

fuzz2050

In that case, the belt would win hands down, since it does the same thing, but at a fraction of the weight, and without the need for a chain-case (I love the idea, but have had nothing but bad luck).They seem to require a frame designed especially for the mounting of a chain case.