Hobartlemagne 

It is fun, but if I were to say there were any advantages to riding fixed, they would be:

1-ease of maintenance
2-they're good for certain types of training.
3-you will be allowed on a velodrome track (as long as it is brakeless)

667

So you are denying the momentum and weight benefits of a fixed gear bike on the street?
Who’s ignorant?

Yoshi

The momentum argument is generally speaking a fallacy. The momentum in the cranks helps you pedal through deadspots, but if you are letting your cranks do that for you then you are actually slowing yourself down by increasing the resistance.

In my personal experience I have found it easier to climb on a fixed-gear compared to a road bike with a similar gearing. In this case I believe it is because of the momentum - climbing at low cadences requires a lot of force on the pedals and generally results in sloppy pedal stroke. Not having to pedal through dead spots helps you maintain your rhythm which makes it easier to climb. However it is possible that this speculation is completely incorrect, as soft-pedalling through dead spots on a road bike would accomplish the same thing. It warrants more thorough experimentation/analysis.

However climbing in a large gear at low cadence is biomechanically less efficient than low-gear/high-cadence so a road bike is better at climbing than a fixed-gear with a typical gear ratio.

Of course fixed-gear drivetrains are more efficient at transmitting torque from the cranks to the wheel than a road bike, due to a lack of derailleur and a straight chainline. The difference in efficiency between a fixed-gear and a single speed is probably negligible.

As for weight, the lightest bike I own is a track bike (around 16lbs) but there are road bikes out there that weigh much less than that. Weight only makes a real difference when climbing so for general street use a light weight bike offers little advantage over a heavier bike, everything else being equal.

MIN 

fixed gear no handed trackstands to impress the townies.

667

I disagree.
You are correct, if you are letting the cranks do the work for you, but if you are powering the cranks, any momentum is an energy benefit over a free-wheel at the same cadence.

jotog

It's a grand idea for ANOTHER bike.
It's soooooooooooo quiet.

Yoshi

If what you say is true, then you have discovered free energy. Since free energy violates the first law of thermodynamics, I'd say it safe to assume that your assumptions are false.

In any case, if you are applying a relatively constant amount of force on the cranks during the entire rotation then your chain is staying taut, meaning that NO momentum is being transmitted from your rear wheel to your cranks.

Yoshi

I drew a little picture to explain what I mean about the taut chain (ph33r my MS Paint skillz):

pedalling:


Not pedalling:


Force is transmitted from the cranks to the wheel along the top part of the chain, force is transmitted from the wheel to the cranks along the bottom part of the chain. It's not possible for force to be transmitted along both at the same time (even with a perfectly tight chain, though it's easier to see with a slightly slack chain).

667

No, I haven't discovered free energy and I'm not talking thermodynamics. I'm talking experience, real world comparisons and undeniable conclusions.

Yoshi

Refer to my diagrams. I am talking about physics and engineering, not zero-blind, single participant case studies.

RE: my free energy comment.

If what you say is true, and the momentum supplied to your cranks from your rear wheel acts as an energy benefit over a freewheel, this means there is a net positive.

Now let's assume a completely zero loss environment here, in other words there is no resistance on your bike at all, it will continue to move forward forever. Ignoring the fact that if you are pedalling there is NO momentum supplied to your cranks from your rear wheel (as shown in my diagrams), the rear wheels momentum (the product of its mass and angular velocity) is transmitted to your cranks via the chain. You then supply power to the cranks, thereby increasing its momentum. This combined momentum is transmitted to your rear wheel, increasing its momentum. So far so good. However you imply that you get a benefit from the momentum that is transmitted from your rear wheel to your cranks and back. This means that if you don't pedal, the momentum in your cranks is going to somehow increase the momentum in your rear wheel.

Think about it - if you don't pedal when you have a freewheel, your cranks don't move. If you don't pedal on a fixed-gear, your cranks do move. You are implying that the moving of your cranks means you need to put less energy into the system to maintain your speed which means that the moving of your cranks is putting energy into your rear wheel (more than it is taking away). Obviously this is impossible - the energy that your cranks can put into your rear wheel cannot be greater than the energy put into them by the rear wheel in the first place.

Yoshi

Here's the deal, a fixed-gear drive train is more efficient than a road bike drive train, all else being equal. It may be more efficient than a single speed due to the efficiency of the freewheel mechanism (I have not verified this, but it would make sense).

That alone can make a big difference. The momentum transferred to your cranks can make it easier to pedal if your pedal stroke is sloppy, but it doesn't make it more efficient.

It sounds to me like you are noticing that it is easier to pedal (especially uphill) on a fixed-gear because of the momentum carrying you through dead spots, and you are noticing the increased efficiency of the drivetrain. The problem is that you are attributing one to the other.

667

^ This is reasonable.
I can’t argue physics - im too much of a layman.
I guess I was touting the perceived benefits of fixed-gear biomechanics.

Zodiac71

I got one because I needed something to stand by while drinking PBR and smoking Parliments

667

...and somewhere to put your spoke cards.

zacked

A fixed gear will climb slightly better on a hill that A) has a linear slope and B) has a slope that is in the proper torque range for your legs. A geared bike will climb better in the real world.

ilikebikes

Preferance, its all about preferance, I know about six guys (myself included in the six) that tried fixed gear, everyone hated it but one. Does that make it suck? No, just means five guys in Philly didnt like it for whatever reason, but we all like single speeds including the one guy that likes fixed. (he now owns two bikes, one fixed and one single speed) its really as simple as that. Im sure youll hear this same story some day but in reverse

Gordo789

I just have more fun on mine. I haven't tried SS yet though, but riding fixed is more fun than riding with gears for me.

ilikebikes

and thats what its all about, whats more fun for you Ill be god damned if Im going to ride a bike because everyone else tells me I should! No sheep here

juggleaddict

+1 . . . keeps bloodflow = less lazyness uphill (or it's a placebo, one)

roadfix

I don't find that to be true. I regularly ride two different bikes, one fixed and the other ss, geared identically, up the same hill every week. On the ss I can't tell the difference between that and the fixed gear when grinding up this hill. The fixed gear does not assist me in any way.

caloso

I built up a conversion for commuting and wet-season training. It's simple, reliable, and fun. Here's a training benefit: it broadens your power band. With a derailler bike you can choose the optimal gear for your speed and cadence. That's really the whole point, right? The thing is, you get used to riding in only the correct gear.

On a fixed gear, you're often in the "wrong gear." Maybe you're going down a decline or with a tailwind and you're in too low of a gear, maybe you're going up or into a headwind and you're in too high of a gear. With the former, your only choice is to spin it up; with the latter, to grind it out. Over many miles, your legs get used to spinning higher cadences at the top and pushing higher torque at the bottom.

Previously during a race or a group ride, if the pack suddenly accelerated I would have to drop a cog, stand up, and mash. After riding fixed, I can spin up to a higher cadence, remain seated, then drop a cog. Much smoother and faster acceleration. Or on rollers where I would previously gear down, now I have the low cadence power to stay in the big ring and power over the rollers. So that's a concrete benefit I have realized from riding fixed.

squeakywheel

Exercise. It works better than a coach yelling "PEDAL PEDAL PEDAL" and chasing you in a car.

ianjk

Zen is easier to achieve with a fixed wheel.

....that and babes love my skidz.

bicyclridr4life

Weight makes a big difference when going down the hill, too. Heavier bike = slower up hill and faster down hill

667

I don't know about that. From back in high school I remember seeing a bowling ball and a penny hit the ground at the same time when dropped from the same height.

Try it right now with a penny and something substantially heavier (like a can of soup).