Rolling Resistance (RR) - Understanding Tires

[DrkAngel]

While at high speeds, Rolling Resistance (RR) is a minimal factor, but at speeds below 20mph, it is a major factor and well worthy of consideration!

At 50mph the rolling resistance is approximately 3.5% of the energy required from "Mountain Bike".

An alternate source (Schwalbe) demonstrates the transition between rolling resistance and air resistance as the major energy robbing factor as speed increases.

"Speed" is in KPH.
I removed "Gradient" factor-lines.

As demonstrated, 18kph looks to be the transition point of RR being surpassed by AR (Air Resistance) as the primary resistance creating force.


Please note that RR increases at a linear rate ... 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 etc.
While AR increases at a geometric rate ... 1 - 2 - 4 - 8 - 16 - 32 - 64 - 128 etc.

As speed increases, RR becomes an increasingly minimal factor-consideration.

 

[Fabian]

I really like your graphical representation of these numbers. It's visually informative.

 

[DrkAngel]

eBike tires

I did a lot of shopping for low RR, durable and affordable tires.
These 2 look to be great bargains!

Might have just found my new - Best Bargain Tire!

Schwinn - 26" x 2.125" heavy ... and it doesn't look too impressive ...
But!
Kevlar Belted!
40-65psi!
Large size and nearly flat tread is ideal for my eTrike!
Price: $15.38 & FREE Shipping on orders over $35. (I bought 2 & $5 gloves to get free shipping)



I lucked into finding these tires that meet my requirement almost perfectly!
Tread is a a nice compromise between the mountain bike tread and the smooth tires that came with the eZip.
26" x 1.90"
Pressure @65psi is acceptably "good".
City/commuter sidewall protection.
Kevlar reinforced for puncture resistance.
Reflective sidewall.
The reflective stripe, though a cheap add-on (under close inspection), is a nice bonus.

- only $15.72 each.
This is great bicycle parts source w/free shipping on $100 order (USA only).

 

[Fabian]

The Schwinn - 26" x 2.125" heavy looks like a tyre that promises long tread life with improved puncture protection - in the league of the Schwalbe Marathon tyre range, but for $15 as opposed to $60 +

 

[Sidewinder Jerry]

I use Kendra 838 26x1.95. You can get them at (D i c k's Sporting Goods) for $15. They are patterned after a motorcycle tire. The Rubena V99 City Hopper is another good tire; you can get these in different colors.