Mid drive ?

[Haystacks]

These threads always make me chuckle, they also end up in the same circular argument and the cause is very clear. Nobody ever qualifies what 'efficiency' is, nor what the environs in which this 'efficiency' is measured are.

For example, a road bike, on tarmac is efficient and proficient, however a roadie on singletrack is neither efficient nor proficient, on the other hand a XC bike on singletrack is efficient and proficient and also efficient and proficient on tarmac.

If i took two riders on bikes that are diametrically opposed IE roadie and fatbike, and set them on a two legged race, one leg on road the other on gnarly single track, each bike having to complete each leg and then combined the times, i know the fatty would win, the guy on the roadie gave up after 3 pinch flats and finally snapping his fork within the first 200m of offroad riding, the tortoise rolled on. The tortoise was also smart, he put 30psi in his tyres for the tarmac section.

 

[RunForTheHills]

These threads always make me chuckle, they also end up in the same circular argument and the cause is very clear. Nobody ever qualifies what 'efficiency' is, nor what the environs in which this 'efficiency' is measured are.

For example, a road bike, on tarmac is efficient and proficient, however a roadie on singletrack is neither efficient nor proficient, on the other hand a XC bike on singletrack is efficient and proficient and also efficient and proficient on tarmac.

If i took two riders on bikes that are diametrically opposed IE roadie and fatbike, and set them on a two legged race, one leg on road the other on gnarly single track, each bike having to complete each leg and then combined the times, i know the fatty would win, the guy on the roadie gave up after 3 pinch flats and finally snapping his fork within the first 200m of offroad riding, the tortoise rolled on. The tortoise was also smart, he put 30psi in his tyres for the tarmac section.

Maybe not. It depends on the skill of the rider. This is a fun video to watch.

 

[K PierreR]

You really cannot make generalizations about riding in America but I have noted a few things about the states.
If the area was inhabited before the advent of the automobile, the riding is more difficult and dangerous.
If the area was developed after WWII, the riding is generally safer with roads designed with some grading and safety in mind.
If the area has been ruled by a single political party for a long time, the riding is generally much more difficult and even crappy.

 

[Kayakguy]

Maybe I missed it, but I don't think anyone has mentioned another reason for rolling resistance: all tires (including auto tires) flex as the they roll, especially in the sidewalls. This flexing costs energy, which is the reason why auto tires get hot after an hour or more on the freeway. It's also one reason why low inflation pressures create more resistance.

 

[fooferdoggie]

Maybe I missed it, but I don't think anyone has mentioned another reason for rolling resistance: all tires (including auto tires) flex as the they roll, especially in the sidewalls. This flexing costs energy, which is the reason why auto tires get hot after an hour or more on the freeway. It's also one reason why low inflation pressures create more resistance.

it really makes a difference. When I had my low wheelbase recumbent with a fairing I tested tide widths and pressures. I have a hill I coasted down every day and I could see How just changing pressure changed the speed

 

[RunForTheHills]

it really makes a difference. When I had my low wheelbase recumbent with a fairing I tested tide widths and pressures. I have a hill I coasted down every day and I could see How just changing pressure changed the speed

Supposedly too high a pressure makes a tire bounce more and increases rolling resistance as well. I am not sure how much that really affects it, but there are online bike tire pressure calculators for calculating the ideal pressure based on the tire size and rider/bicycle weight. On my commuter bike, I like to error on the side of a little lower pressure for a more comfortable ride, but not so low that I get pinch flats or it is hard to pedal.