With urban riding, remember that you often need to thread the needle at slow speeds. If you have to mash through those slowdowns, your stability will suffer and you may end up trackstanding under a cement truck.

After seeing the hills in Nashville, I don't think I'd even be that high on the gearing.

48x15 in the city doesn't sound like much fun
I like 48x16 or 48x17. I loose a lot of top end with 17 but if it's heavy traffic, it's better than the 16.

48x16 wasn't fun when I was running it.

I like 49x18 imo.

+1

I recently switched my Dodici from 49/18 to 49/17. After one ride, I switched back to 49/18.

What do you end up running on the track?

49x16 warm up
49x15 F200M

(I also use a completely different fixed for commuting, and a different one for track)

That would be a bit too limiting in top end for me.
48x17 is similar and that feels good. I guess it depends on riding style and topography.

48x16 has been perfect for running around as well as riding with a friend, pacelining.
It's not as good in heavy traffic otherwise

47/17 over here. I am able to hold ~22 mph real easy.

spin to win.

I ride around Chicago (flat, heavy traffic) and the northern burbs (mild hills, less traffic) every day, and I rode around Austin (moderate traffic, lots of hills) with 48/17 and love it.

8.4 meters development.

Even Eddy could only push 7.9m.

http://images.wikia.com/ciclismo/pt-...rckx_hora1.jpg

Not to be a jerk, but if it's too big for Eddy, it's probably too big for you.

Hey Chicago...that's where I started cycle-commuting! 25 years ago. :notamused: No bike lanes in those days. Then Mayor/cycle-commuter Daley got elected and the rest is history. If I was commuting in Chi nowadays I'd use 46x16 fg. But, I'd have a Surly Pugsly w/2.35 studded Nokias, too. :p

Don't live in Nashville, but 35 miles SW. Past Franklin and Leiper's Fork out where the Natchez Trace Parkway crosses Natchez Trace Road. There're a few 18-25% gradients out here, but I know all the ways around them. Sometimes, I'll climb one and do switchbacks just to stay sharp w/that skillset, though. Nighttime fg rides on the NTP are the best. One can do 40 miles and not have a single car pass.

85 gear inches 48/14. old school marin hybrid converted into single-speed. my friend who's a bike messenger rides 56/16 fixed gear and rides brakeless. I think he is crazy and he is fast. i guess bike messenger are really hard to pass and beat. his bike is really like less than 15 pounds super light mavic wheel and IRO bike frame weighs like 3 pounds.

i'm 24. i hope i don't feel pain when i hit 30.

Even more reason to use lower gears

Lots of people do lots of things, that doesn't mean you should too.

your right. might do down to a 48/16 for the winter. rode 42/16 for like 1 yr then 42/14 for like 4 months and for this summer went up to a 48/14. my leg is spinning out the 48/16 easily and riding at 110-120 cadence only reason i switched to 48/14 down to like 90-100 lol.

You realize thats like 28mph right?

yes np. i only ride on flat road will go down to 48/16 or 42/14.

My pain all came about when I hit 40. Now at 47, it's all about trying to survive :)

yea 48/16 not bad if you're fit.

I ride 48-17 because I'm halfway between being a jackass kid and a boring adult.

always feels easier to ride in the summer so go higher gear but then when winter comes gear down.

I've felt pain plenty of times before I hit 30 two years ago.

Probably spinning out down hill, I run 45 /16 , I've run 48/15 for a year and it did hurt my knees, but I live in a high traffic area with lots of lights so slightly gearing down felt nice

It's not about being fit. I also refuse to believe your rolling average is 28mph.