Dynamic shaft drive bicycle
 

This is an informal review of the Dynamic shaft drive bicycle.

After surviving a heart attack last year I treated myself to a new bicycle. Since I already had a mountain bike, a old steel road bike, a 3-speed Raleigh Tourist, and a number of junkers, I wanted something unusual and-more important-something I could ride around town and use for commuting to work. I bought the Tempo model without a suspension fork, and it has more than met my expectations. The company sells several styles: mountain, road, folding, all with shaft drive, most with suspension forks. All are sold on line.

The Dynamic Tempo is a fairly conventional Taiwanese aluminum bike with good components. The shaft drive is the only thing that makes this bike unusual. When riding I hardly notice that there is no chain, except that the bike is CLEAN. This is the main advantage. I can ride in office clothes without getting sprocket tooth marks on my pants and without the annoyance of pants clips or –even worse – having to change clothes to ride. The drivetrain takes no grease or lube of any kind, except for an application from a grease gun once a year, depending on use. (There is a Zerk fitting underneath the bottom bracket.) This feature alone would make the bike a good commuter.

Another feature adds to the attraction: the 8-speed Shimano hub. I have used 3-speed SA hubs for years. They are fine, but the Shimano is way ahead in terms of smoothness, ease of use, and range. The gear range on the Dynamic is about 30 to 90, not far from the old 10-speeds. This range is perfect for riding around town and for day rides. Adjustment of the hub is easy, and as for service, my local lbs told me to “ride it till it dies”; don’t sweat the service. Because of the shaft drive the range of gears cannot be changed – no sprockets. Also good for in-town riding are the 700-35C tires and the available fender kit.

The brakes and other components are more than adequate. I had assumed I would change the seat for a Brooks B67, which I have used for years, but so far I have not made the change. The seat is not quite as comfortable as a Brooks for long rides (no other seat is), but it is certainly good enough for now. I had to change the stem to get the bars higher and closer to the seat. This kind of adjustment is normal, but it does reveal one problem in buying on line. An lbs would normally change a stem with no charge as part of their setting up, but any changes to a mail-order bike are at the customer’s expense. The pedals were too small, so I replaced them with some mountain bike platforms which I already had.

Along with the bike, I also bought the fender and rack kit. The fenders were the usual pain to install. The front wheel and forks are set up for disk brakes, an option on this bike, and the disk brake tabs on the fork interfere with the fender support wires. The solution? Bend the wires. Eventually I got everything straightened out.

I have ridden the bike several hundred miles in and around Sacramento including some dirt roads. My longest trip has been about 30 miles along the Sacramento Northern rail trail north to Rio Linda. I have had no problems at all. The hub shifts perfectly, the bike is very quiet, the 35mm tires have taken everything in stride. When installing the fenders, I did loosen the rear wheel and pull it out of the dropouts. This is no harder to do than on a derailleur bike. I have not as yet had to completely remove the rear wheel to fix a flat. I suppose I really should do a practice run. Unhooking the hub control cable seems to present the main difficulty.

The total cost with the additional kits and shipping was about $900. I’d recommend this bike to anyone as a commuter and fitness bike. I hope to get years of service from it.
M Riley

I'm glad that you enjoy it and are making good use, I'd love to have one purely as a conversation peice, do you have any pictures?

it's good to hear reviews from an actual owner rather than: a link to a retail site, a query on wether anyone has anything to say and the ensuing flippant comments from people who have about as much experience on the matter of the original poster.

with modern computer design bevel drives have gotten alot more efficient than the older ones, even though it'll never figure in with belt and chain drive, but there are good arguements to me made over exposed chain drives and their need to be clean and lubricated and so far there are few if any enclosed chain bikes available.

I've long preffered shaft drive motorcycles, I hope that it becomes more popular in cycling too.

The thing that looks most interesting to me is the whole... enclosed drivetrain thing. That way, if I crash, the drivetrain is protected. Not so on a conventional bike.

/me is interested in the Sprint... damn you...

Just thought I'd drop in some links and pics:

Dynamic Bicycles

Here's the Tempo (Hybrid) mriley wrote about:
http://www.dynamicbicycles.com/admin/bikes/l170240.jpg

And the Sprint (Touring-Commuting) bhtooefr mentioned:
http://www.dynamicbicycles.com/admin/bikes/l161908.jpg

Thanks for the write-up mriley!

It's nice, but all we really need are some plastic chaincases.

It looks like the shaft unit could be fitted onto any bike. it looks nice.

Well, if you read their site, they claim that the shaft unit won't work on a regular frame.

And, reading Sheldon Brown's glossary entry on shaft drive, I'm inclined to agree with them:

I'm the original poster.
A fully enclosed chain would do much the same as the shaft drive, at least as far a cleanliness goes. It's just not easy to find one except on some 3-speeds.
As for putting it on another bike, it won't work. The dropouts are really different and of course the bottom bracket has gears inside it.
I should mention that shaft drive bikes have been around for more than 100 years. I first saw one in the 1960's, a girls model Pierce bicycle from about 1900: spring forks, wooden rims, the shaft running inside the left chainstay. Very elegant, nothing as neat is made today. Of course it was one speed. Pierce went on to develop the Pierce Arrow motorcar, the BMW of its day.
M Riley

A old answer for a question no one asked

Heh, I ask "why can't they make a bike with an enclosed drivetrain!?!?!!?!?" all the time. :) My *&#&@# chain is always getting wet and grindy.

Here: http://www.cannondale.com/bikes/07/c...odel-7SS8.html

Looks like a chainguard to protect your pants, difficult to tell from the picture whether it would keep the chain protected from the elements as well.

Anyway, I think the Dynamic is cool and I'm glad the OP is happy with his new bike!

Take another look at your frame. The shaft drive is going to want to be placed right where your chainstay is currently located. Notice on the pictures posted above the chainstays have been moved higher on the seattube and dropout. Shaft drive requires a frame designed for the purpose.
An enclosed chain case has many of the same advantages at a lower weight and probably lower cost. However a shaft drive is probably still lower maintenance and less susceptible to environmental conditions. I'm guessing these bikes are nearly comparable to derailer equipped in performance. I doubt there is much of an efficiency loss due to the shaft drive.
Craig

It encloses the chain. Seen them at the LBS.

It's a Hebie Chainglider. The chain is fully enclosed from the elements and the case actually floats right on top of the chain (no frame attachment).

You've seen the whole Cannondale bike or just the chainglider? Which LBS? I've been looking for a chainglider and live in the DC area.

why do I always think these threads are spam?

It appears possible to identify one Victor G. Rivera only in the context of the drive-shaft bike promotion:

Cool Tools

I like the aspect of rebuilding the bike with the appreciation of the ruggedness of the shaft. How much thinking had to go into construction of that story! Most of would be overwhelmed by the shape of the frame and of the rims under real circumstances. What the heck is the 'better than new condition' achieved with the help of the customer service?

I tried to get one - I was told that you can't even order that bike in the US - you can only buy it in Europe. Cannon Street Premium/Ultra. What a bummer.

I HAVE seen bikes with a fully enclosed chain case in person. Here's the bike - The Breezer Uptown 8:
http://thehubbikecoop.org/itemdetails.cfm?LibId=44154

http://thehubbikecoop.org/images/lib...own8d_07_m.jpg

Here's the official page:
http://www.breezerbikes.com/bike_det...ptown&new=true

http://www.breezerbikes.com/im/bikes/new/uptown-d.jpg

It's the "new" (versus the "classic") Breezer Uptown 8. That's the only bike I've ever seen or heard of in the US that comes with a full chain case, though...

PaulRivers;

I agree that the Uptown 8 is the only bike I am aware of with a full chaincase except for the Chinese and Indian utility cycles which weigh a ton and some Pashley models. Never been able to figure out why the American importers/distributors of commuter bikes do not spec them with full chaincases. The cases have to be available to them as similar bikes for the European market, also from Taiwan or China, have them fitted.

IMO all chain drive utility bikes fitted with gear hubs should include a well designed full chaincase.

The figures I have seen for shaft drive bikes indicate a approximately 2.5% power loss for each bevel gear pair. True when introduced over 100 years ago and still true today so far as I know.

Very interesting info on the Dynamic bikes...and me sitting here waiting for my income tax refund to come in at anytime now.:innocent:
Ernest

Hell, mine is already spent. Now I'm just waiting for the check to come in so I can pay my bills!!!

The only reason I can think of is that perhaps adding a full chaincase makes it more complicated to get the rear wheel off if you get a flat. Plus, honestly, they can make the bike look kind silly if they're the big one like on the Uptown 8.

Being that an ideally maintained derailleur only claims to be 98% efficient, I highly highly doubt a shaft drive bike is anywhere near that. Also, other people on this forum have posted experiences with shaft driven bikes and talked about feeling a noticeable loss of efficiency for a shaft drive - I don't think 2.5% power loss has any basis in reality. Whether it's enough of a loss to matter to you is another matter - my internal gear hub is slightly less efficient than a derailler, but it's lower maintenance and better reliability (no frozen gears) for winter riding is by far worth it for me. Personally, I'd be very hesitant to get a shaft drive for efficiency reasons, but personally I cannot imagine buying a BMX bike either. :-)

2.5% per gear pair is 5% for the shaft drive plus any losses from the gear hub. The 98% efficiency for derailleurs often claimed is not accurate either as they vary depending on the gear selection even on a well maintained and adjusted derailleur system. Interesting tests of gear hub and derailleur efficiencies were done some years ago by Chester Kyle and Frank Berto and written up in the IHPVA Journal, available for download.

IMO a properly designed chain case should not interfere with rear wheel removal. Note the "properly designed" qualifier. A full chaincase only looks silly to those who are not used to seeing bikes with them. Many Europeans look at American commuter/city bikes and think they look ridiculous due to the lack of chain protection and standard generator lighting. The Breezer appears to me to be a truly practical city or commuter bike, one of very few available here.

Hi All. I've just bought a slightly used Incline Cruz 7 bike - 700c wheels, front suspension, shaft drive with 7-speed Shimano Nexus hub. (Presumably very similar to the Dynamic brand - the shaft part is made by Sussex. Weighs about 35 pounds BTW.) The friction and roughness in the drive train seemed excessive, so I added grease to the hole under the bottom bracket, and to the bevel gear in the rear (with the plastic cover removed). It's significantly better now, but there is still some roughness. If it was a chain-driven bike I'd say that bottom bracket feels like it's over-tight and perhaps undergreased. But for this bike, perhaps it's normal? If I wanted to check and adjust and grease the bottom bracket bearings, how would I take it apart? Does the grease added to the bottom bracket bevel gearing also reach the axle bearings? How much grease should I add to that hole? (I added about 10 cubic centimeters, using a syringe.) Thanks for any advice.

I had an Incline :

http://www.bikeforums.net/showthread.php?t=520607