What do you think of this bike?

[lolymoly]

My buddy thought this bike was cool and far superior to normal mountain bikes: www.dynamicbicycles.com. Is this really a necessary feature to have on a bike?

[Dr. Moto]

I'd be interested to know the weight difference between chain drive and shaft drive. My guess would be the shaft drive is heavier. I noticed this site doesn't list the weights of their bikes.

A chain is a pretty efficient drive mechanism for a given weight. Chain-driven bikes also have the benefit of a hundred years of development and refinement. I don't know if I'd bet on version 1.0 of shaft-driven bicycles, but I've never been an early adopter.

[alcahueteria]

I saw a shaft driven bike on the price is right like 5-7 years ago. It was the first time I had seen anything like that. It was crazy. I guess it could be ok, if nothing ever broke, but it would suck if something did. You could always hook it up to a 7 speed internal hub to get some gears, but I would be very wary of that thing.

Actually you might not be able to put it to an internally geared hub. It may(probably) need something special back there.

[Dr. Moto]

Actually these bikes use the Shimano internal hub. The website quotes 7-8 gears over an "extremely wide range" (I couldn't find any comparisons of tooth ranges). Funny quote from the website: "How many gears do you really use anyway?" Ummm, all of them.

[alcahueteria]

Yeah, I find it odd that these bikes have been around atleast 5 years, and yet I've never seen one in person...seems a bit sketchy to me.

[Thunder13"]

Maybe if I play my cards right I can build my dream F/S frame using this kind of drivetrain. Chains don't allow for any expansion between the bottom bracket and the rear hub. well aleast not very well... They tend to break. Not that I won't find any problems with shaft drives, but i have been shopping around and found some very nice new things that are being done like helical universal joints. http://www.heli-cal.com/Html/Products/ujoints.htm

I only need to find the right servo gear boxes, and a telescopic driveshaft that will handle 3000 inch pounds of torque.

[Dr. Moto]

Chains don't allow for any expansion between the bottom bracket and the rear hub. well aleast not very well... They tend to break.

Chains themselves might not expand easily, but that's one of the roles of the rear derailleur, to take up the slack and maintain chain tension. This system has a lot of flexibility that would be lacking in a shaft-driven system. I wonder how they handle that? Some kind of flexible coupling?