A belt drive singlespeed

Belt drive bikes are nothing new. Archibald Sharp mentioned belt and steel band driven bike transmissions in his 1896 text “Bicycles and Tricycles”. I haven’t talked much about belt drive, but I have mentioned bikes on this blog before that use a belt instead of a chain. I know about some of the problems historically associated with belt drive systems (slipping, stretching, reduced efficiency, one piece design etc.), but to be honest I have never actually ridden a bike with one. Well, I wish that I were going to Interbike so that I could test ride one of the New Spot Brand Bikes that uses a Gates carbon drive belt. Spot will have these bikes available to ride at the Outdoor Demo, so I hope that some of you reading this will get a chance to take one for a spin.

There are definitely some advantages to belt drive for a bike without derailleur gears. I expect the carbon belt to be clean, light, quiet, and pretty much maintenance free. I am interested in hearing your impressions of this system. Let me know what you think if you get a chance to ride this bike at Interbike.

Via: Quickrelease.TV
Photo from Spot Brand’s website

Also, I just noticed you can read more here.

Posted

September 14, 2007

James

Tags:

belt drive, Interbike, Spot Brand

Comments

25 responses to “A belt drive singlespeed”

Fritz

September 14, 2007

I won’t be able to make the outdoor demo, unfortunately. I wouldn’t mind trying it out, though.

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keithwwalker

September 14, 2007

If Buell and Harley Davidson motorcyles can use belts instead of chains, then so can bicycles.

The newest Buell makes 146hp/82ft-pounds of torque. It’s drive belt weighs 1 pound, 75% less than a comparable chain, doesn’t need adjustment for it’s service life, which is probably 60-75,000 miles (chain would only last 30k).

The only disadvantage is that the bike has to be engineered more around the belt than a chain would. Not a problem for mass produced bikes, but probably an issue for custom frame builders.

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spokejunky

September 15, 2007

Ride these things up in Sugar Mountain and Snowshoe during their wet seasons to see how mud clearance affects the cog teeth and belts.

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jay bushby

September 16, 2007

I rode one of these at the royal college of art bicycle design school. this was the bike i had a go on http://strida.co.uk/demo/index.php.

i have to say it suited the folding bike appliction very well it was clean which is great if you carrying the bike while wearing posh suit no oil to stain your clothes.

but the belt just wasnt as efficent as a chain it feels not as a solid tension like metal on metal provides.
the future in racing no. but it has its benfits for cheeper bikes that dont get used as often (saves rusty chain and foldable bike commuters its spot on

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Tarun

September 19, 2007

I think as material science improves, we will see belts eventually replace chains everywhere except racing, and then even racing once the problems are solved, as there are many advantages over chains. If Shimano and Campy spent as much time on belt drives as they have on e-shifting, it would probably be a reality now.

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Johan

September 25, 2007

Those belts are very sensitive to misalignment and dirt. The tension is quite high and there’s no flex in the belt, so if some gravel gets caught by the belt something got to give. It seems to be both more sensitive and also a lot more expensive than a chain, so it should probably need to be encapsulated. Also with a traditional looking frame the rear triangle needs to be openable in some way of course. That said I really like the idea of a even more quiet, grease-free bicycle with less maintenance.

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EddyKilowatt

September 25, 2007

What’s the efficiency of such a belt? Seems to me that anytime you have an elastomer involved at the contact interface, you’ve got hysteresis and thus loss.

But then, you do have to decide what sort of chain to compare it to… the clean, freshly lubed chain in the lab, or the gritty, greasy, dried-up looking thing that I find on my bike at the end of most rides…

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bikesgonewild

September 26, 2007

…18yrs ago, gary fisher & i looked into doing the original “fisher gemini” tandem using an enclosed (in the large bottom tube) gates belt drive system, between two, toothed bottom brackets…final drive would have been regular chainrings, chain, derailleur & sprockets…
…no ‘chain’ stretch on longest length, less wear (remember, this was an mtb tandem), lighter…still an interesting concept…

…eddyk…w/ no figures at hand, as i recall gates offered decent efficiency…nowdays & with a large enough market, perhaps edges of the belt could be shaped so less energy is lost to side friction, maybe graphite impregnated surface areas ???…

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j9

September 29, 2007

Rode the 29″ Spot w/ belt drive at the Demo and LOVED it! As a female I have been interested in the fit of the 29″ frame. As for the belt drive, it was smooth and really quiet. I am really excited to see it’s future and how it holds up over time.

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Anonymous

October 1, 2007

The word is in…. massive slipping. Don’t believe the hype. Another company scores marketing points and IB coverage.

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Ron

October 30, 2007

belt drive is not as efficient as chain… i’d never have something like that on my bike.kj

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Doug

November 1, 2007

I have been riding and racing my Spot singlespeed cross bike here in Colorado. I got my bike Sept 5th. I love it. It is very efficient. It engages instantly. I have not had any slippage problems.

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Loudva

August 18, 2008

Seems to me that the nay sayers should at least try it before they knock it. The chain is a great system but it has been in use for over 100 years. Don’t you think it’s time for some innovation in the drive train arena. Lets leave resistance to change to the conservatives. The only way these systems will get better is if development is given serious consideration. Just look at how suspension technology has progressed over the last 10-15 years.

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Loudva

August 18, 2008

Sounds to me that all the nay sayers should try it before they knock it.

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Chris Trees

August 24, 2008

I rode 50Km a day for over a year on abelt drive bike I made using agates carbon fibre belt. Is very responsive and rigid Jay Bushby must have been talking about an old rubber faced or Kevlar cored belt

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JJ Daddy-O

September 4, 2008

Where can I get the parts? I am building a fixie now and would love to try one out.

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mr mess

October 18, 2008

What a great idea. I’ll buy a belt when it becomes available, and put it on my current bike. Oh dear, I can’t, because you need a special frame to be able to use belt drive. Well f*ck that. If it can’t be retrofitted then it can f*ck off and die.

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Anonymous

October 29, 2008

Wow. What a bunch of closed* minded individuals.

*maybe ‘feeble’ would be a better choice.

If you combine the modern internal geared hubs with this type of belt drive you essentially create the most maintainance-free bicycle imaginable.

No fiddly derailers, no oily chains. Belts are going to be much stronger and not break like chains will do. It’ll greatly reduce the complexity and increase the reliability of pretty much any bicycle.

Also look at the type of belt being used. See the ‘teeth’? That equals no slippage. They’ll be fine in wet conditions, unless, of course, you like riding in streams up past the hubs of your bikes.

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S. Johnson

November 20, 2008

Ok, here’s the thing. We can’t say they won’t break because the few broken chains I have seen in my life came after years and years of riding them. Who has been riding one of these new belts that long and hard to say they won’t ever break?

Also, they are not “maintenance free.” That is a misnomer. They are impossible to fix, you just have to replace it after it wears out (which sounds like it will be a long time). I worry more about wearing out the plastic gears.

It is pretty tragic that you cannot retro-fit your favorite fixie. I would have done it just for a lark and to test it out before I bash it.

But, I think these will be successful for pedestrian riders, no pun intended. Those who just ride their bikes for fun or on short trips and are not that keen on fixing things themselves will probably love the cleanliness of the new design.

PS My fixed gear is also silent when it is clean and lubed…

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Anonymous

January 31, 2009

dont see a problem with toothed belt drive – kevlar reinforced is good – belts are used in car engines to drive the valve cams and last over 100Km running at high temperature and speed. And very popular on motorcycles.
Surely it would be possible to make a special belt with a breakable link by weaving the kevlar around a metal pin at each end and using a hinged metal link to join the ends.

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Jeroen

March 15, 2009

Its really unbelievable that so many people who never have driven a belt-drive bicycle are so sure that it’s not as efficient as a chain-powered bike. Try before you yell, folks!

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MarkSingleton

March 23, 2009

I’ve done 9000 miles on belts. The bicycle is a Moulton fitted with a Rohloff Speedhub. The combination is brilliant and maintenance free (I’m an idle sod). Gates Polychains used to be Aramid (Kevlar) reinforced but the new carbon belts are 20% stronger. They’ve introduced a new belt for bicycles with an 11mm pitch to help stop teeth jumping. The 8mm pitch belts are just as strong and a “snubber” stops teeth jumping more effectively. With small wheels, you need a higher ratio (100 teeth to 23 teeth in my case) which requires the 8mm pitch. You can see a picture here: http://www.flickr.com/photos/24082504@N06/2664851030/in/pool-moulton_bicycle/

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Anonymous

July 22, 2009

Well, you all forgot one major obstacle, and it is HUGE!! Smart arse vandels who deliberately cut and slash the BELT! I have been done over twice now. Solution! back to the chain as they cant cut it so easily.
rev dr g

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SimoninEaston

August 5, 2009

re: theft, I was thinking it'd be easy to carry a spare – very light and flexible – and then I started to think about fitting it and Doh! I've just realised that there's no way to add a joint in a belt… now that's got me thinking…

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Anonymous

August 22, 2009

http://web.me.com/matthewreeves/Site/belt_drive.html

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