Re: Dual-Chain drive train

zen cycle <funkmasterxx@hotmail.com> writes:

On 12/29/2024 10:39 AM, bp@www.zefox.net wrote:

Zen Cycle <funkmaster@hotmail.com> wrote:

https://www.bikeradar.com/news/buffalo-utility-s2
>
Made for developing countries to allow for easier transportation on
cargo bikes, without the exposure and complexity of an external
derailleur or hand-operated shifting (for an internally geared hub). It
was developed and patented with the help of SRAM.

Are derailleurs really that bad? A whole new bike for the sake of a
granny
gear seems slightly extreme. Internal pawls at small radius are going to
be more stressed  and harder to build than a rear sprocket of larger radius.
I'll admit that the narrower flange of a multispeed rear hub impairs
the
lateral strength of the rear wheel, but a hub with flanges spaced to leave
room for a two-cog stack would be vastly stronger. What is the "exposure"
alluded to above?
Thanks for reading,
bob prohaska
 

 Third-world use by people with little to no technical ability. Their
 bikes are heavily misused and abused, and generally speaking the
 riders/owners have very few resources that could be applied to fixing
 something that failed.. An external gear-changing system doesn't last
 long in those environments.

 
Derailleur chains require frequent replacement due to wear.  Expense and
logistics would likely be a problem in the Buffalo application.
Non-derailleur chains can wear in with the cog and sprocket and last for
years without requiring replacement.