On Mon, 28 Dec 2015 09:15:11 -0000 (UTC), Edmund
wrote:

On Sun, 27 Dec 2015 11:47:12 -0500, Frank Krygowski wrote:

On 12/27/2015 5:19 AM, Edmund wrote:
On Sat, 26 Dec 2015 16:44:21 -0800, Sir Ridesalot wrote:

On Saturday, December 26, 2015 at 7:25:28 PM UTC-5, Edmund wrote:
On Sat, 26 Dec 2015 21:29:27 +0000, Tosspot wrote:

Snipped
But that assumes a typical 1/8th pitch. A 3/32 pitch saves another
4%
on rolling resistance from the drive chain only.

Do you have a source for that? I don't see why a larger pitch should
have better efficiency and 4 % is quite a lot.

Edmund

Tossport used the wrong terminology. There is NO difference in PITCH
between a 1/8" chain (4/32") and a 3/32" chain. What is different, as
A.
muzi pointed out, is the width which is what the 1/8" and 3/32"
indicates.

Cheers

Thanks for that and my bad, 3/32 isn't bigger but smaller then 1/8
(4/32")
IF that was the pitch that would theoretically have a better
efficiency. The big question is : does a 3/32 chain have better
efficiency In Real Life and what about durability and "standard" does
it require special tooth wheels? $$$$$$$$ Then it is no option and
certainly not for my first attempt to make a handbike.

Someone once said "A month in the lab can sometimes save up to an hour
in the library." Or something like that.

It's not always true, of course. (I still think you need to buy a used
bike and a set of calipers and just measure what you're curious about.)

But you really should hit the library and read _Bicycling Science_ by
Wilson. It contains a lot of fundamental background knowledge that you
will need, assuming you continue this project.

I don't like to be hindered by any kind of knowledge of the subject :-)

Edmund

Hopefully your "day job" isn't designing bridges or airplanes :-)
--
cheers,

John B.