A little science related advice on Bicycles.

[susheel]

I'm posting this here since I don't want to clutter up the Banter thread. So if there's anyone who has any opinion...let me know:

I am an avid buker and own two...a 21 speed ATB for recreation and a single speed cruiser for daily commute to work. Well, a new bike which uses a shaft drive instead of the standard chain has come on the market. I am thinking of trading in my second bike for this. It is rather expensive...costing about twice the price of standard ones.

Is there anyone who is familiar with this type of bike and it's advantages? Apart from looking cool, the lack of chain rattle, and lower maintenance.

My daily commute isn't very gruelling and doesn't put too much stress on the bike. Contrary to popular opinion we do have roads in India.

[BrianT]

I think the general criticisms have been weight (heavier than regular bike) and increased mechanical complexity. I wouldn't be too sure about it being easier to maintain, but you would probably know better than I about that. Anyway, the idea is not new, but it hasn't really caught on, at least not in the US.

[edthedoc]

I'm not sure how much comparison can be made with motorcycles that have shaft drive: I used to ride a Moto Guzzi California 3 with shaft and the lack of chain meant it needed less adjusting, oiling, the ride was smoother with good low down grunt (the rest of the bike was 'orribly unreliable though).

Shaft drives generally only appear on large motorcycles (BMWs, Honda Pan Europeans, Harleys).

How this could relate to a bicycle I don't really know.

Have you looked here?http://www.ethicalwebsites.co.uk/zero/faq.php?back=index.php

[susheel]

Thanks edthedoc,

Actually that was one of the first sites I came across when I was looking for information about this particular drive train. However, since it is a promotional site most of the information isn't really helpful

I am looking for a more critical lowdown. Something hands on from a third party. I do realize that the thing hasn't caught on much and I was rather surprised to find it being offered by a major bicycle manufacturer here.

I am wondering if the lack of enthusiasm to what I see as being a rather cool system is because of the feeling that a 'bike should have a chain'. I have enough physics to assume that there will be a slight loss of power but this shouldn't be too much of a problem for non-power biking.

Some bikers tend to be a bit prejudiced now and again. I often grind my teeth and bear it when one of my cycling purist acquaintances go on about how inefficient the 21 speed atb I drive is in comparison to his single frame rigid cruiser. The gist of his argument is that it is all fluffy new technology. I once told him that the cycle he was riding was fluffy new technology a 150 years ago.

[a_unique_person]

All I know is, the better the bike, the better the chances of it being stolen.

[garys_2k]

I'd assume you'd lose some mechanical efficiency driving through those two right-angle gear drives. Chains and sprockets are pretty efficient.

[roger]

Well, http://www.ethicalwebsites.co.uk/zero/faq.php?back=index.php is the faq for a manufacture of shaft drives for bikes. It is 1kg heaver than a chain mechanism, and 90-95% efficient as opposed to the 98.5% efficiency of a chain.

The only advantages that I was able to find them list on the site was the improved safety from not catching your clothes in a chain. I would assume if there were other advantages they'd be advertising them.

[scotth]

gary and roger beat me to the exact points I wanted to make.

The bike will require more effort to ride at the same speed, all other factors (wind, tires, road surface, etc) being equal.

[gnome]

Originally posted by a_unique_person
All I know is, the better the bike, the better the chances of it being stolen.

Yer not kidding! One of my co-workers just recovered from a motorcyle accident that totaled the vehicle. After buying a new one, it was stolen the day he got it.

He's having a bad month.

[BrianT]

I ride a recumbent, so that's fluffy new technology from only about 80 years ago.