Return of the Elevated Chainstay
- Thread starter Dr S
- Start date
Dr S":1gt9xy4h said:MikeD":1gt9xy4h said:
Nice and quiet.
Belts have proven more efficient in engines too. Why not on bikes? I'm always snapping bloody chains too. Dirty, noisy bloody things.
Bikezone in Oxford had a belt-driven singlespeed in the window earlier in the year; drive belt made by Gates, a pretty reputable firm in the field of such things as far as I know.
Only personal experience of drive belts is Dad having to replace one on his electric lawnmower many moons ago!
David
MikeD":23yg4bh1 said:The question is not "why not?" but "why?". Comparing a straight run of bike chain to a straight run of belt there's bugger all in it for efficiency. You've got to use hub gears if you want a geared belt-drive bike. You have to have the frame made specially for it one way or another. The belts and sprockets are wide which leads to all sorts of packaging issues. The belt is lighter than a chain but the sprockets are heavier than chainrings. You need to run lots of tension which the bearings don't like much. You have to spray it with water to stop it being all squeaky in dry/dusty conditions.
Urban commuter/utility bikes yes. Mountain bikes not yet
But you journos often get it wrong. I was sat on thee throne last week reading a MBUK christmas special from 1989 and under a picture of Tomac at full flight on his Yeti C26 it says ' we expect to see the Tioga Disc drive wheel on lots of bikes in the coming years. Wether the suspension fork takes hold remains to be seen' or words to those effects.
Embrace change!
:shock: 
The belts are meant to last longer than chains by a considerable factor IIRC.From the gates site:
What are the benefits to the Carbon Drive Systems?
Life – Lab testing has shown the Carbon Drive belt to last more than twice the life of chains.
Light Weight – The entire system, 2 sprockets and a belt, weighs less than just a typical chain.
No Stretch – The Carbon Drive belt does not stretch over time like a chain. This means you don’t have to re-tension the belt, or replace the belt due to stretch. This also means no excessive wear on sprockets due to stretch.
Smooth – The instant engagement of the Carbon Drive system gives an unparalleled smoothness that chains can’t meet.
No Noise – The Carbon Drive belt is virtually silent.
No Lubrication – The Carbon Drive belt does not need lubrication to keep it running smooth and silent; this means no grease on your hands, socks or pants.
Open Tooth – The patented open tooth profile of the Carbon Drive sprockets allows mud, dirt, rocks, and other debris to pass right through without a moment of hesitation.
What are the benefits to the Carbon Drive Systems?
Life – Lab testing has shown the Carbon Drive belt to last more than twice the life of chains.
Light Weight – The entire system, 2 sprockets and a belt, weighs less than just a typical chain.
No Stretch – The Carbon Drive belt does not stretch over time like a chain. This means you don’t have to re-tension the belt, or replace the belt due to stretch. This also means no excessive wear on sprockets due to stretch.
Smooth – The instant engagement of the Carbon Drive system gives an unparalleled smoothness that chains can’t meet.
No Noise – The Carbon Drive belt is virtually silent.
No Lubrication – The Carbon Drive belt does not need lubrication to keep it running smooth and silent; this means no grease on your hands, socks or pants.
Open Tooth – The patented open tooth profile of the Carbon Drive sprockets allows mud, dirt, rocks, and other debris to pass right through without a moment of hesitation.
MikeD
Senior Retro Guru
Not enough out in the real world yet to know for sure. And it'd be interesting to see the details of the lab test.
Need numbers
Derailleur setups tension themselves
They are smooth and quiet, yes. Except if dusty, when they start squeaking. Unless it's really manky, singlespeed chain setups are smooth and quiet too - most transmission noises are due to derailleurs, not chains per se.
Big plus for utility bikes. Big irrelevance for enthusiast mountain bikes. You still have to clean it
A system that works so well that they've launched a new, redesigned Centre Track version with better ability to disperse mud. I think "rocks" is a bit optimistic - you might get half a lump of pea gravel to pass thought the sprocket if you're lucky
And yes, predicting the future is always tricky. But the Gates thing has been doing the rounds for years and shows no signs of going big yet. I'd go for a belt-drive Alfine townie, though.
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Norco has had a belt drive bike (Ceres) in their lineup since last year (the drive side dropout bolts on to the seat stay for belt service). Looks like more of a hipster-mobile than an actual off road bike. An old friend who has a LBS in a town on the other side of Toronto (Rocki Mountain's abode) had one in his window when I was out that way in March. Unfortunately I had stopped in before my uncles funeral up the street, and was not dressed for test riding bicycles, so I have no idea how it rides.
