I think the key phrase people were talking about as a phenomena on why fixed bikes will help pull you through the dead spots of the stroke and not loose effeicency is the fact that..

the rear wheel is acting like a free-wheel in an engine of a car. A spinning mass helping keep the engine or in this case the pedal stroke continuous and smooth.

With a non fixed bike, all the rotational mass and energy is lost.

I give up, you people are hopeless:crash:

http://www.youtube.com/watch?v=7WMi5TUJDso

if you relax and let the cranks pull your legs thru on a fixie then your slowing down or just fighting your legs somewhere else in the pedal stroke, zero sum game

there is no magical loss or gain of energy or efficiency here

what a fixed gear does do quite well is remind you instantly if you don't pedal smoothly

from the bike's perspective it takes X amount of work to make it go Y miles per hour PERIOD no matter how it is pedaled pushed or towed, it doesn't matter what gear ratio is used or anything else, you have to overcome drivetrain friction, rolling resistance, and aero drag and that's it, being a fixed gear doesn't alter the laws of physics

i tried my gf's single speed today and i must say...coasting feels absolutely perverse. it's wayy too easy and doesn't feel like i'm riding a bike. I don't like it it's out of control

riding a geared roadbike, i definitely KNOW im using more efficient energy (putting less stress on myself to do the same amount of work)...

But, when I ride my fixed track bike of similar weight, i feel as/if not less tired than riding a geared roadbike.

Both are the same weight roughly so it would seem that the roadbike would tire me less. But, I ride my fixedgear smarter when it comes to pacing myself, keeping my spin up, attacking hills earlier and cleaner than on a geared bike. This more alert riding style is definitely what equalizes my laziness on a geared roadbike.


obviously, all things equal (and that is hard to do), the geared bike should be more efficient for daily use.

I ride both. Singlespeed/fixed is my daily commuter ride. No, it's not as fast as my road bike but I get a great workout with it and it's fun to ride. I've ridden the fixed gear on long rides and it's quite a workout. I am no fan of descending even with front and rear brakes. On many group roadie rides I'd get left behind eventually if I were on the fixed gear bike. We've got lots of rolling countryside and some long climbs that would put me at a disadvantage. But the fixed gear riding has made my road bike riding stronger. And going on long(70-80-100mile) road rides has made me a stronger fixed gear rider. Climbing Monte Sano on both bikes, I'm faster with the road bike and less tired when I reach the top. Other riders are quite impressed when I ride the fixie up Monte Sano. (3+ mile climb, 5.5% overall grade with some 8-9% stuff thrown in there to keep you awake)

On long distace open roads, no doubt fixed is tougher. How much is the question. I think 1: 1.5 is too high unless you are talking mountains.
My guess would be 1.2 - 1.3 for rolling to moderate hilly terrain.
Break vs. no break;) is another important factor. No brakes on long descents can really kick your ass and wear you down.

I would say those are the two biggest factors, terrain and brakes.

Okay, fair enough.
I agree. However on a steep enough hill with a large enough gear your pedal stroke is going to get sloppy. Most people have a really sloppy pedal stroke when they get out of the saddle. In those situations a fixed-gear is advantageous because it will smooth out your pedal stroke. True, in doing so you are wasting energy, however that is better than falling over.

In any case, when the climbing starts to get real (say over 10% for over a mile) I much prefer a road bike to a fixed-gear.