rubber compounds

On Fri, 23 Feb 2018 03:36:30 +0100, Emanuel Berg
wrote:

Jeff Liebermann wrote:

https://www.bicycling.com/bikes-gear/components/know-your-rubber-quick-start-guide-mountain-bike-tire-design
From the same paragraph as the above quote:
Hysteresis A dynamic measurement of energy
loss in the rubber compound, this can also
relate to rolling resistance or tire
"grip." A 70sA compound typically has
little energy loss, while a 40sA has
a large percentage of energy loss.

BTW what notation is 70sA and 40sA?

70 Shore A and 40 Shore A.
The "A" defines the type of penetrator used.
A is for soft rubbers, while D is for hard.
https://en.wikipedia.org/wiki/Shore_durometer#Durometer_scales

There's a bit of a muddle over the term durometer. Some say it's the
units of measure, some say it's the name of the instrument, and some
say it's both. Methinks it's the instrument name.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558