I personally size my gearing based on the top end speed at proper cadence that I want. A 46x16 should give you a top end speed of ~35kph (22mph) at ~96rpm with enough room for speed increases based on cadence.

In NYC I ride 47x18 or 49x16. Both are good for the city. But, in neither case am I w/o a brake. Being new to fix riding and riding brakeless is an invitation to taco a front wheel or worse in city traffic. Riding with a brake allows you to make abrupt slow/quick stops to account for the motherf****r taxi cab drivers who will cut you off in traffic and then make a screeching stop right in front of you. When you have traffic flowing on side of you, and parked cars on the other your only choice is to stop behind the cab. And in many cases you have only 10-15 feet in order to make the stop. But, if you are confident in your abilities then skid and skip away to your heart's content.

Regardless though, even having brakes doesn't prevent sh*t from happening. My last accident was on my road bike when a driver was playing cat and mouse with a taxi cab and made a left turn from the center lane down 9th Ave and cut me off while I was in the left lane. I was going ~40kph and only had enough time to turn the bike into the turn, but still wound up hitting the car at the drivers side.

Of course, many people riding fix in the city go slower than I would in order to account for the above potential scenarios.

For comparison, the elite riders at the Track WC in LA this past march, based on the 200m times of under 11secs and close to 10secs, and based on the gear selections of 48/49/50x14, would have a cadence of ~150-160rpms.

In my 47x18 I start to lose control above 130rpms down steep hills. I want to ride track so, I need to have a better spin. The good thing about using a soft gear down steep hills is you simulate the speed (>60kph) and cadence of a track sprint without stressing out your legs. The power comes from separate training.


The reason people for the most part use 48/49 chainrings is that is what comes stock on off the rack track bikes or cranksets. You need to buy smaller chainrings separately. And no one other than Shimano makes track chainrings below 46T. And their Dura Ace chainrings are like ~$80 each.

Don't feel bad. I run anywhere from 38/15 to 38/20, depending on where I'm riding and whether it's on pavement or dirt.

I run 46:17, and it works well for me. The town I'm in is a little hilly. I can brake comfortably most of the time, though if my knees are mad I use my brake.

I think I'm the only fixie in my town.

U sure you're not the only bike rider in your town? :b

I started with a 42/18 (63") and ride as high as 52/16 (88") on a good day.
For most rides or commutes I find a 42/16 (68") up to a 44/16 (74") works best.

My current herd and gearing:
Motobacane Mirage 52/16
Motobacane Nomade 52/18
Free Spirit 52/18
Miyata OneTen 52/19
Van Dessel Country Road Bob 44/16
Lotus Elan 52/20
Schwinn Le Tour 42/16

Using the calculator, I found I could go with a 48/19 and get the same gear inches as a 38/16, so I may go that route. Most of the pre-built fixies come with 48's up front anyway and it's easier to change out a cog, PLUS it'll give me the ability to go up to more gear-inches if necessary.

I am experimenting with running an old '83 Trek "road racing" bike with 12 speeds as a single speed. Shortened the chain, and have it running at 42 x 17, or 67 gear inches. This is a bike that I'm mostly using around my inner-city neighborhood, with stop signs or traffic lights every two hundred yards or so. Stop and go...stop and go.

So far, 67 gear inches seems to work well for "round the neighborhood" riding. It is easy to stop at a red light, and then spin back up to cruising speed. The combination of just 67 gear inches and half century old legs means my cruising speed looks rather slow to the younger guys who go whizzing past me on the road.

But, easy spinning in an easy gear has been helping my aging knees. When I wake up in the morning, my knees are a bit stiff and sore. After an hour or so of riding in an "easy" gear at 80 RPM's or 90 RPM's, my knees and legs feel good - the soreness and stiffness is gone. I finish a ride feeling about twenty years younger than when I got out of bed.