On Sat, 4 Jul 2020 17:21:44 -0700 (PDT), Rich
wrote:

On Saturday, 4 July 2020 17:28:28 UTC-4, Andre Jute wrote:
On Saturday, July 4, 2020 at 4:21:07 AM UTC+1, Rich wrote:
Unless the stupid bike is powered, why endure that ridiculous rolling resistance?

You may be inexperienced or a troll, but I've already settled that question, he http://thorncyclesforum.co.uk/index....16360#msg16360

Andre Jute
I don't follow the fashion, I create it

PS. BTW, you're ill-informed. Low pressure balloons have a lower rolling resistance, so there is no "ridiculous rolling resistance". Where'd you ever pick up that dumb street corner myth?

You are complete wrong on this, it's not possible for a tire with a larger contact patch to have lower rolling-resistance than a small, higher inflation tire. Where did you learn physics, grade-school?
I know a lot of people on mountain bikes who switched from 2.25" tires to 1.9" to lower rolling resistance.


https://en.wikipedia.org/wiki/Rolling_resistance
Rolling_resistance = CRF * Normal_force
where CRF is the coefficient of rolling friction.

CRF is determined by the road and tire materials and construction. It
doesn't change with inflation pressure.

Normal force is pressure perpendicular to road surface. As the tire
pressure decreases, the size of the contact patch in square-inches
increases. The weight of the rider and bicycle do not change with
tire inflation pressure. Therefore, the only thing left to change is
the "ground pressure" which goes down as the size of the contact patch
increases in size. This is why vehicles that travel on ice and snow
use big balloon tires with a big contact patch and minimal ground
pressure.

Since CRF is constant, and the Normal_force decreases with lower tire
pressure, the Rolling_resistance also decreases.

When you take the same rider and bike, and switch from slicks to
knobbies, you reduce the ground patch area. That increases the ground
pressure, which causes the rolling resistance to increase. That's one
reason why riding knobbies on pavement is like dragging an anchor.

Anecdotal Drivel: I don't ride much any more, but when I do, I prefer
slicks (on pavement). Nashbar Slick ATB Tire 26x1.25 NS-SBT. Not
exactly balloon tires, but cheap and good enough for my limited
requirements. Something like this, but different size, and without
the sidewall decorations:
https://www.nashbar.com/continental-gatorskin-street-mountain-tire-26-x-11-8-0118365/p1202379





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