London Fixed-gear and Single-speed

Hi, sorry to ask again...

Can anyone give me some advice on gear ratios?? I'm getting my first singlespeed freewheel custom built, and have been asked what gear ratio I want. The standard he (the guy that's building it) uses is apparently 52T 18T. In one of the threads, it seemed like most people were going with 48/16 or 17. is this wildly different, and if so, how?

I have read the other threads about gear ratios and am still confused! Sheldon Brown's calculator was fine til it got to the "chainrings" bit.

This will be my first commuting bike, my heart's set on a singlespeed, but I didn't realise it could be so complicated.

If it's any use, I'm 5'4", female and only moderately fit. Cheers muchly.

give this a whirl

http://software.bareknucklebrigade.c...it.applet.html

46 - 18 would be better.
The ratio he wants to give you isn't going to make for a fun ride around town, too long to get up to pace.

+1 to what ma3k said, ideally you'll want to get a GI or anywhere between 65-70", for riding in town, the gear inch calculator that tick.tick.tick posted is a good one and will show you different alternatives to get to the magic numbers, anything over that is a bit big, for a first timer, you'd get used to it, but it'd be difficult to spin and come winter it'll be much harder.
The only issue is whether you'll be riding using 700c tires or 650c, that will make a difference, but you can select tire size in the calculator as well..

Fantastic. Thanks for your help. Mucho appreciated.

I also came across this explanation, which shed light on the matter:
http://www.surlybikes.com/spew11.html

i ride 47/17. plan on changing to 47/18, though.

I have ridden 48/13 and it was a bit of a beast - 48/15 was a lot nicer (and more skid patches)
Out of interest, does anyone have a fixed cog on both sides of the wheel with different ratios, one for riding (48/13) and one for playing (have no idea!!)?

47:17 does me good. ^ 48:13 is monstrous.

46:18 is good for me, only im thinkin about going 48:18 so i can get up a bit more speed on flats.

Matt0 yes double fixed hub is the way to go if you want two different ratios.I have one and its great.

glad to hear it, i'm changing to 47:17 as soon as my new chain ring arrives.
i'm looking to spit the difference between 48:18 and 48:17

What would be a good ratio for play rather than riding? Im assuming a lot lower, but i have no idea how much.

ps. the 48/13 was for riding around Cambridgeshire - Dead flat!!

what kind of play? anal play?

dildo play?

your daughters school play?

Nimhbus you sick pedo fuck.

Check out the TrixieDix thread.

anal play with the teeth on chain rings... are you mad?!?!

in that respect 2:1 is a good ratio, but every time I try all I get is a 0:1 ratio which is definatly less fun

this is useful for working out ratios. Lower is better for tricks and stuff, if you're into that, and higher is better for going fast.

^ repped, very useful.

(don't want to hijack the thread, but I'm not allowed to post new yet)

My first fix which is slowly taking shape in my bedroom workshop got vert. drop outs and the purist in me thinks that I can't use an eno or somesuch. So I worked out that my current chain stay will allow for the following options:

47x16, GI: 76", Skid patches: 16
49x18, GI: 71", Skid patches: 18
51x20, GI: 66", Skid patches: 20


Now, given that I have no clue what these feels like, i've never rode a fix before, my current commuter is a 10sp road bike, and I find the 50x15 (GI: 90) to be "magic" for me, mind I do have front and rear brake now, but I think I'll ditch the brakes all togehter on the fix. What would you guys pick for going around london brakeless on a daily basis?

Cheers

You've never ridden fixed and you want to ride brakeless?
Use your brain dude.. and I don't mean by putting it through a taxi!

70GI(ish) for London.. as has been posted about 4000 times on this forum

Why ditch brakes- they are really helpful when it comes to slowing down?

Gotta start somewhere, don't I, Of course I wouldn't throw myself out in london traffic on my first day on a fixed without breaks, or the week after for that matter, it's a learning experience just like anything else. But I reckon if I wan't to ride fixed without breaks, the best way to learn is to actually do it, no?

70ish it is then, thanks.

Why do you want to ride fixed with no brakes?

Practising on the streets for when he hits the velodrome innit.

Ah yes, nothing like the controlled environment of London's streets to prepare one for the utter carnage of the individual pursuit..

Demz velodromes be crazy shit innit. Man dem got stabbed upside the hed last times we went.

(I have no idea what I just wrote either. Bed calls...)

Quite. Although there's a motorbike to look out for in the Keirin.

Wish I could make a list with all the (in)sane reasons, but I guess it boils down to me wanting to build a fixed with minimum of bits on it, and then of course at least try to use it. Bit like 'look, no hands, no hands'.. Not saying it's without risk or the most clever thing, but that's never been the way I've gone about doing things anyway.

Btw, (just reading through the posts), I didn't say I definitely didn't want to have brakes on the bike, just that I think I'll ditch them, meaning I want to get the gearing right for riding brakeless, but I might end up using a brake anyway. Or just go back to my good ol' roadie. What really floats my boat is to build the bike, as light and minimal as possible.

option 1. see http://www.londonfgss.com/thread9446.html

option 2: have someone document your experience here

option 3: if this hasn't put you off, then ride 50 GI.

You can do what you want.. just don't expect me to be laying flowers at the scene of your demise and don't fscking crash into me or it will be the scene of your demise.

If you want to build a bike as light and minimal as possible then build a unicycle.

I know. keep the road bike. Spray it all white, including the tyres and lock. Lock it up somewhere on your normal commute route.

Rep biiatch