Redundancy. On a fixed gear bike, you can use your legs to resist or even skid and that sort of counts as a rear brake. On a freewheel, you can't do that, so if you loose your front brake (i.e. cable breaks) you have no brakes at all.

Also, 100% front braking increases chances of endover

idk if its a track bike thing but my all city big block would not allow me to use the brakes off my road bike. arms were too short so pads were at the tire and not rim.

It depends on your normal cadence and your terrain. I normally spin aroud 90 and have a few hills to deal with so my 53/22 setup works great for me. I can muscle through the tough climbs but can sustain 20-21 mph on the flats when necessary. 90 rpm nets me around 17-18 mph on 700x23.

[MENTION=281169]rex615[/MENTION] I think you misunderstood. I was advising that if they have a single speed (with a freewheel) that only a front brake is not an option, obviously. That when freewheeling you should either have a rear brake (like dirt bmx) or both front and rear. Obviously both brakes are "redundant" on a fixed gear but plenty of people still do it. I wouldn't exactly call back pedaling or skidding an emergency brake, and I wouldn't call safety redundant. But this is a bit off topic isn't it?

Currently rocking this around SF and its ok -- thinking about throwing on a 19 in the rear but going to give it some time!

I was agreeing with you and attempting to explain this statement you made "I'm sure someone could give you a technical explanation why."
After rereading my post, i can see it was not clear. By redundancy i mean, that it is desirable to have more than one brake on a freewheel bike.

If i've got both front and rear brakes, do I also need to wear a helmet ?

That's really interesting. I've never heard that before either. I'm 72'' tall and I'm currently riding ~75 gear inches. Started at 71, but it's all flat where I ride and I wanted something a bit larger. So far 75 seems pretty much perfect for me/the terrain.

I've heard that your optimal gearing is based on your date of birth, altitude, IQ and attitude. But, that's just me.

[MENTION=281169]rex615[/MENTION] My fault. Guess I misunderstood. Glad we're both right.

[MENTION=401797]rreahard[/MENTION] Yeah for sure. Your height is a good starting point I guess. The "perfect ratio" seems different for everyone particularly in the variety of terrain. I'm still leaning toward 48x19 and we'll see how that goes.

Haha. Also your diet. Vegetarians aren't going to exert as much force as protein-packed, blood boiling cave dwellers.

[MENTION=392491]xscottypx[/MENTION] 27" versus 700c? Not sure why your brakes wouldn't reach. Maybe short reach versus long reach?

Technically speaking, you don't NEED to wear a helmet, nor do you need brakes. Just go with the flow and hope for the best.

Oddly enough, I saw a guy with no brakes, no helmet and riding a freewheel on a critical mass ride once. I watched him the entire evening waiting to see how he stopped - was totally hoping for a Ted Shred maneuver, instead I got Fred Flintstone. I wondered how often he goes through shoes?

critical mass brings out the worst people. i was riding in the city once when one was going on (i didnt know at the time) and i followed for a whole one block and promptly said "screw that noise" and went on my merry way without them. idunno how people can do those rides all the time

pretty sure it is this

For real?

There's a small group of bike activist peeps in Phoenix that are really cool and fun to hang out with...they were doing it so I thought I'd tag along...and that will be the last time.

I don't really get it...we want people to respect us and give us room to ride and whatnot, but then you get a critical mass and it turns out being a bunch of idiots riding all over the road, in front of traffic, running stop signs, hopping curbs, purposefully slowing traffic to the point where it's annoying, etc and then they expect cars to be respectful of them. There seems like there'd be a better way to do bike advocacy, but what do I know.

yeah activism is one thing, but critical mass aint it. thats just a reminder to all the drivers how many of us there are and why they hate us

I have an ex who lives to piss people off, she always does critical mass.

Gear Ratio Advice
 

48/19 for me. I have a short commute with a pretty big hill (uphill on the way home). Rode fixed but eventually went to SS because of that hill. Also I run two brakes.

I like those big and big combinations. I have a bike with 53/20 which works out to about 72 gear inches (40mm tires). I also have one with 42/16 and 50mm tires and the ratio works out very nearly the same. The 53/20 just seems smother and looks better.

I think the OP wants to remain economical and keep chainring as is. In which case, I'd suggest starting with 48/18.

Agree 100%

The Monday after a Friday critical mass, the cops have a vendetta against anyone on a bike. All the freaking clowns come out for CM rides, then disappear and leave everyone else to deal with all the pissed off cops and drivers. I couldn't stand those people(generally).

Also, I'm sick of everyone thinking that they deserve road space when they are on a bike. I mean, some people just shouldn't be on the road. Perfect example, on my way in to work this morning, on a super busy stretch, this chick, probably in her 20's riding a squeaky pos junk shop 10 speed, wearing a wobbly helmet, flip flops, all kindsa **** dangling from her "sweet vintage 10 speed", clogging up traffic. Big stupid smile on her stupid face, barely paying attention, no sense of being defensive whatsoever, caught up in the "I'm making a difference" moment blah blah blah. Goddamnit get on the ****ing sidewalk!....

I was up to 110 gear inch and then the IQ thing resulted in an "ideal" gear of 42":(

YES!!! I love to ride down Central Ave in Phoenix...I used to hug the curb because it's fairly busy, but they recently put in sharrows, so now I don't mind taking the full lane and just hauling ass down the street. Everyone else is complaining about being buzzed going down Central and we need protected bike lanes, and blah blah blah. Don't get me wrong, protected bike lanes are great and all, but the reason you were buzzed was because you were taking the lane on a busy street and only going 12mph. Kick it up a notch, or go two streets over and ride through the residential neighborhood with bike lanes and speed humps and stop complaining. These are the same people that post 20 page rants about a UPS truck being temporarily parked in the bike lane. For ****s sake, just go around the truck.