Belt Drive Single Speed?

Fletch6 · 07-22-2007

Has any one ever heard of a belt drive being used on a single speed?
It would seem that it would be perfect.

rockyuphill · 07-22-2007

Jericho Bikes did one a while ago (but their website never seems to be running), and Orange bikes recently showed one. I seem to recall another SS manufacturer using a toothed belt recently, and cleverly running an elevated stay that eliminated the need to have a removable dropout to get the belt over a chainstay.

Nat · 07-22-2007

Quote:

Originally Posted by Fletch6

Has any one ever heard of a belt drive being used on a single speed?
It would seem that it would be perfect.

I haven't heard of it on a SS, but a long time ago I heard of a belt drive bicycle. I guess the problem was pebbles, rocks, twigs, and other junk got sucked in between the belt and the drive wheel too easily.

Sixty Fiver · 07-22-2007

I have always been a fan of chain driven wheels for my two wheelers...belt drives can catch crud and slip when wet and shaft drives on motorcycles have this annoying torque shift issue.

This is why high performance bikes (of both kinds) still use chains since they are still as good as it gets.

Nat · 07-22-2007

Quote:

Originally Posted by Sixty Fiver

I have always been a fan of chain driven wheels for my two wheelers...belt drives can catch crud and slip when wet and shaft drives on motorcycles have this annoying torque shift issue.

This is why high performance bikes (of both kinds) still use chains since they are still as good as it gets.

I think the belt drive bike had a toothed belt, which wouldn't slip, but it would easily get jammed up by a pebble.

I saw a shaft-drive bike a long time ago. I think the issue there was overly-high friction that our puny power output couldn't overcome.

Fletch6 · 07-22-2007

It seems the orange bike should have used a plastic hub a it would be Lighter. I would think the metal sprockets would not be needed on a bike.
Also yes I had not thought about dirt and stuff, but this would not be as much of a problem on Rail Trails or road.
Another thought for Sheldon Brown. Hook in a Nuvinci or rohloff and it would be perfect.

Caffeine Powered · 07-22-2007

Hmmm. Nope, I'll keep quite for a few more months on this one.

aka brad · 07-22-2007

Quote:

Originally Posted by rockyuphill

Jericho Bikes did one a while ago (but their website never seems to be running), and Orange bikes recently showed one. I seem to recall another SS manufacturer using a toothed belt recently, and cleverly running an elevated stay that eliminated the need to have a removable dropout to get the belt over a chainstay.

Jericho indeed "did one" a while ago (see below) and it looks surprizingly a lot like the Orange

. The truth is mud and dirt on the belt proved to be very problematic, causing Jericho to halt production.

Brad

Moustache rider · 07-22-2007

3 speed belt drive.

Miker J · 07-22-2007

The old fashioned steel bicycle chain is going to be very hard to beat. Especially for SS applications. Studies suggest it is extremely efficient at power transfer. It is very reliable on a SS. Easy to maintain. And very cheap.

On the other hand it's always good to see folks looking for ways to improve.

Lactic · 07-23-2007

Here's a prototype belt drive from Spot I saw last week. Very trick and mated to a rear King SS hub. I can see how small rocks and/or mud could play havok with the belt interface though.

Nat · 07-23-2007

Quote:

Originally Posted by Lactic

Here's a prototype belt drive from Spot I saw last week. Very trick and mated to a rear King SS hub. I can see how small rocks and/or mud could play havok with the belt interface though.

I wonder if a belt shaped like a ladder would work? The central holes or squares would allow the teeth to push debris through the belt, much like a metal chain does.

bbrz4 · 07-23-2007

that would be much too weak to drive a bike

heatstroke · 07-23-2007

how do you change the belt ?

Nat · 07-23-2007

Quote:

Originally Posted by bbrz4

that would be much too weak to drive a bike

Why do you say that?

aka brad · 07-23-2007

Quote:

Originally Posted by heatstroke

how do you change the belt ?

The rear seat stay is bolted to the the dropout.

Brad

berrywise · 07-23-2007

Back in 2004 the booth next to use at Interbike was pushing a belt drive bike. The problem they had the time was you had to use bikes with elevated chainstays. I know some companies like Redline/Seattle Bike Supply were interested in the idea for their chopper bikes.

The idea of a bolt together rear stay is a pretty cool idea to get around it. Figure if something like a big motorcycle can use a belt I don't see why a bicycle couldn't.

Pluto Pilot · 07-23-2007

Check out Singlespeed Dream. This guys been riding and testing one for two months now. You'll have to poke around a little, but info is there.

Sparticus · 07-23-2007

Quote:

Originally Posted by aka brad

Jericho indeed "did one" a while ago (see below) and it looks surprizingly a lot like the Orange

. The truth is mud and dirt on the belt proved to be very problematic, causing Jericho to halt production.

Brad

Hey Brad, wasn't there another problem, too? I think I remember Josh saying that in order to keep the belt from slipping, even though toothed and even in dry conditions, the system required lots of tension. Seems to me he said the amount of tension required was hard on bearings as well as being loaded with inherent drag.

I ride motorcycles as well as human powered bikes (both my motos are chain driven) but I can say this for sure -- when a human is only putting out half a horsepower, (s)he needs all the help (s)he can get. Drag must be kept to a minimum to keep efficiency high. But if an engine on a machine is kicking out 30+ hp, then losing a tenth of that amount to mechanical drag is no big deal. Look at O-ring chains on modern dirt bikes -- if the chain is not well lubed, it takes a lot of energy just to spin the back wheel while the bike is elevated off the ground. There's a lot of drag there.

Personally, I don't see much wrong with the traditional bicycle chain for use on a singlespeed. In fact, I think the singlespeed application is where a chain makes the most sense. Trying to mechanically push a chain back and forth laterally across a range of gears is what doesn't make sense to me.

Below, Nat mentions the possibility of a ladder shaped belt. That's what a chain is -- only it's a belt made of metal.

There are more moving parts in a bicycle chain than the rest of the bike's parts put together. The chain we buy so inexpensively at the LBS is an amazing engineering feat. If bicycle chains cost $200 each the average Joe might tend to give them the respect they're due.

--Sparty

jeffscott · 07-23-2007

So we got a ladder shaped chain, wonder if it could be made out of a synthetic, carbon fiber or an aramid, might be light and strong.

May be a different tooth profile on the cogs? as well.

Sasquatchcycles · 07-23-2007

I think that shaft drive is going to be the holy grail of power transfer...it's a matter of R&D money I suspect .the last of the christini MTBs worked pretty well. I thought Jeep had bought them up, but their back with AWD motorcycles.

Nat · 07-23-2007

Quote:

Originally Posted by jeffscott

So we got a ladder shaped chain, wonder if it could be made out of a synthetic, carbon fiber or an aramid, might be light and strong.

May be a different tooth profile on the cogs? as well.

I was thinking something along those lines. Some type of synthetic, low elasticity, high durability. It would have to resist elongating like a rubber band, and resist wearing down as quickly as metal. It would have to have high tensile strength so as to not snap mid-ride such as chains sometimes do. It would have to run quietly without lubricant (no more gummed up chains to clean!). It would have to be flexible enough that one wouldn't need to tension the hell out of it to make it snug. The drive ring an cog would have to not weight as much as a brick (like the Jericho one appears to). I think it'd be worth pursuing.

dRjOn · 07-26-2007

there is an Orange proto doing the rounds too...

Captain Crash · 07-29-2007

Quote:

Originally Posted by aka brad

The rear seat stay is bolted to the the dropout.

Brad

Tricky, but how do you reckon they got the belt on the Orange?

No bolt on drop out:

and nothing funky by the chainring

.

Looks like the chainstay and seatstay are both welded... Thag not understand

CC

Fletch6 · 07-29-2007

Thaug
the orange is a prototype and the belt was cut and welded to join. not very practical for production, but it the belt lasts as long as the single speed dream. I could see it become a reality. the dirt problem reminds me of the bike brakes and V verses disk. for a road or cross bike I could see it taking over. Of course the dérailleur companies will try to fight change to something they cant make lots of money on.

Timo · 07-30-2007

Quote:

Originally Posted by Nat

I wonder if a belt shaped like a ladder would work? The central holes or squares would allow the teeth to push debris through the belt, much like a metal chain does.

You are onto something there. I recall a photo in the older edition of Bicycle Science where the drive belt was two cables, with drive beds run between them. I think the drive beds were composite if I'm not mistaken and it was found that this system was lighter than a chain. I'm not sure if it had rollers like a chain though or what the durability of the design was. Although it was lighter of course than a chain - really on a SS I'm quite happy with chain drive...it's not really an issue to me. Perhaps most companies realize that.

For the drive belt trains, as goofy as it sounds, but to me the best innovation one can make for that technology is a drive train guard that isn't heavy, and most of all doesn't look too goofy to riders. You'd never be able to go over stumps, logs, or ledges though w/o damaging it.

So perhaps the drive belt movement would be better served on commuters, track bikes, etc as the need for drive belt guard would be diminished. With lack of rusting parts it would make sense on commuters.

Nat · 07-30-2007

Quote:

Originally Posted by Timo

You are onto something there. I recall a photo in the older edition of Bicycle Science where the drive belt was two cables, with drive beds run between them. I think the drive beds were composite if I'm not mistaken and it was found that this system was lighter than a chain. I'm not sure if it had rollers like a chain though or what the durability of the design was. Although it was lighter of course than a chain - really on a SS I'm quite happy with chain drive...it's not really an issue to me. Perhaps most companies realize that.

For the drive belt trains, as goofy as it sounds, but to me the best innovation one can make for that technology is a drive train guard that isn't heavy, and most of all doesn't look too goofy to riders. You'd never be able to go over stumps, logs, or ledges though w/o damaging it.

So perhaps the drive belt movement would be better served on commuters, track bikes, etc as the need for drive belt guard would be diminished. With lack of rusting parts it would make sense on commuters.

I think the belt drive, if you could iron out the problems, would be applicable to mountain bikes. If it didn't need lube, it wouldn't get gunked up and wouldn't wear out as fast (maybe). If it wouldn't break, you wouldn't need to carry extra links or a chain tool. It would run nice and quiet all of the time too.

Inertiatic · 08-29-2007

The orange one was a cut and shut prototype

wweeks · 08-29-2007

All 2008 Spot Brand Frames will be belt-drive compatible.

Spot Brand will also be rolling out their new belt drive system at Interbike.

bigwheelboy_490 · 08-29-2007

http://www.cyclingnews.com/tech.php?...007/news/08-28

WTB-rider · 08-29-2007

Just sent the manufacturer, Carbon Drive Systems an email regarding retrofitting their dropout(by an accomplished framebuilder) to an existing frame. I'll post their response for anyone who's interested once I hear from them.

WTB-rider · 08-29-2007

Just heard from CDS/Spot, the dropout can be retrofitted to an existing frame and once installed, it's easy to swap between the belt drive and chain/cog/chainring setups.

nspace · 08-29-2007

Interesting, but not sure I understand the purpose of the dropout. Seems like it would work with a standard dropout?

bikecop · 08-30-2007

That Pricepoint belt drive bike by Delta looks like a potential bargain commuter. High chainstay fixes the "how to install it" problem.
Belts: Harleys use 'em. Racing go-karts use 'em too. They are tough.

spuddy · 08-31-2007

Quote:

Originally Posted by nspace

Interesting, but not sure I understand the purpose of the dropout. Seems like it would work with a standard dropout?

You can't 'break' the belt to install it, unlike a normal chain drive.

unit · 09-01-2007

Quote:

Originally Posted by Fletch6

Has any one ever heard of a belt drive being used on a single speed?
It would seem that it would be perfect.

Not trying to be a jerk...Why would it seem to be perfect? Why are so many people interrested in a belt drive?

I do not see the problem with a chain. It is in-expensive, easy to maintain, and quiet enough for me. Friction? I just do not understand.

Sometimes re-thinking things is a good idea...but I would love some insight as to what you guys are expeiencing that creates a need for something other than the good 'ole chain.

Every time I see a belt drive proto-type on a MTB, I think of the old Mavic Mectronic Derailers.

Thanks (I am not being sarcastic, I seriously am interrested in what problems this concept might fix if perfected)

Nat · 09-01-2007

Quote:

Originally Posted by unit

Not trying to be a jerk...Why would it seem to be perfect? Why are so many people interrested in a belt drive?

I do not see the problem with a chain. It is in-expensive, easy to maintain, and quiet enough for me. Friction? I just do not understand.

Sometimes re-thinking things is a good idea...but I would love some insight as to what you guys are expeiencing that creates a need for something other than the good 'ole chain.

Every time I see a belt drive proto-type on a MTB, I think of the old Mavic Mectronic Derailers.

Thanks (I am not being sarcastic, I seriously am interrested in what problems this concept might fix if perfected)

Chains "stretch," can break, need frequent lubrication, and need to replaced once or more per season along with chainrings and cogs. Chains work great, but I think there's room for improvement.

Andy aka Rut · 09-01-2007

I believe GT is working on a belt drive too. Hmmmmm interesting!!

The belt drive... the new singlespeed of biking.

artnshel · 09-02-2007

Schwinn tried making a belt drive single speed in the late 90's but couldn't quite get the belt to work right.

EliM · 09-02-2007

There's holes in the belt-rings so dirt can be pushed through, so i don't think dirt/pebbles would pose a massive problem.

aka brad · 09-03-2007

Quote:

Originally Posted by Fletch6

Thaug
the orange is a prototype and the belt was cut and welded to join. not very practical for production, but it the belt lasts as long as the single speed dream. I could see it become a reality. the dirt problem reminds me of the bike brakes and V verses disk. for a road or cross bike I could see it taking over. Of course the dérailleur companies will try to fight change to something they cant make lots of money on.

No one says the belt will work on anything but a singlespeed; were derailleurs fit into this arguement has me lost . As far as disc brakes go, yes on cross bikes, no on road bikes. You will never see a disc brake as light as the lightest road bike brake; on the road weight is everything. V brakes have been around as long as mass produced dual suspension MTB's and you still don't see them on road or cross bikes; don't hold your breath. If anything it's the V-brake that has seen it's best day.

Brad

Velobike · 09-04-2007

The Orange beltdrive bike was at the SSWC07