Is it tires

[GeorgeET]

Took a ride on my MB today on a trail. it was 88 degrees here in Texas. still. It was err... challenging. Got home and realized I lost something so I took my road bike down the same path since it was hard packed dirt. It was a breeze what a difference.

Now the MB is maybe 8lbs heavier and has dirt tires, is it mostly the tires or both extra weight and tires. I mean its only about 8lbs. Its 26X1.95 mb and 27X1.25 road tires.

Any old timers still out there to chime in. :-))

[Painkiller]

I would say tire and wheel differences certainly play a role as long as the gearing was there for proper cadence. But more so the weight. To move a given weight no matter the person or size of the person, the energy it takes is the same for everyone. So when asked the question" Is it better to trim the weight off of me or the bike" The answer is trim the weight off the bike. Liken it to this. carrying a 30lb garbage can down a long driveway or a 15lb can. Of course the 15lb is easier. You see the can does not know or care about the energy source. the only thing constant is the weight and energy it takes to move it. Taking the weight off of me does not change the amount of energy to move a given weight of and object or bicycle in this case.

[GeorgeET]

(10-14-2016, 10:57 PM)painkiller Wrote:  I would say tire and wheel differences certainly play a role as long as the gearing was there for proper cadence. But more so the weight. To move a given weight no matter the person or size of the person, the energy it takes is the same for everyone. So when asked the question" Is it better to trim the weight off of me or the bike" The answer is trim the weight off the bike. Liken it to this. carrying a 30lb garbage can down a long driveway or a 15lb can. Of course the 15lb is easier. You see the can does not know or care about the energy source. the only thing constant is the weight and energy it takes to move it. Taking the weight off of me does not change the amount of energy to move a given weight of and object or bicycle in this case.

^^^^^^^^^^^^^^^

Good point. I was reading up on rolling resistance and came upon some counter intuitive info such as that a fatter tire given similar characteristics has lower rolling resistance and that in dirt a softer tire rolls better as it deflects more. However it was also said that knobby tires have greater rolling resistance. Like MB tires.
Sufficient Gearing was available on both bikes. MB 21, RB 12. I really do love the vintage springy Fuji del ray RB. Its so easy to go fast on it.