London Fixed-gear and Single-speed

Dear all,

I hope that I don't incur the wrath of the general fixed-gear/fixed-wheel populus on account of my being a newbie.

I have a mainstream fixed-wheel bike (model name rhymes with "Wangster"), running a 42x16 gearing. Like any sane person, I aspire to a stable of bikes comprising classic old frames built up lovingly, but for the next couple of years, my current bike will have to do.

I'd like to move up to a 46/16 gearing. My LBS (Apex Cycles in Clapham) are very friendly, but don't seem to have a clue when it comes to fixed stuff, so I was thinking for something as simple as this I could swop chainring (+/- chain if absolutely necessary) myself. I'm looking around online for a 46t chainring and am not quite clear what will fit and not. Could I just buy any chainring expecting it to fit, or is there something in particular I should be looking for.

Thanks folks,

Arn.


PS: sorry for jumping on your subcultural bandwagon/contributing to the death of the fixed-wheel phenomenon by buying a Langster/etc.

measure the BCD of your current chainring: http://www.sheldonbrown.com/gloss_bo-z.html and you're set.

Like tick.tick.tick said - make sure you get the right BCD (bolt circle diameter).


You want to make your gear ratio bigger, so if you change your chainring to a larger size you will probably have to buy a new chain (the old one may be too short to go around the larger chainring).

But . . . why not increase your gear ratio by dropping the size of your rear cog ? Cogs tend to be cheaper than chainrings and you can use the chain you have (might need to shorten it).

Here is a gear calculator to work ratios out on . . . .

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


If you are that ashamed or self conscious of your Langster then simply don't mention what bike you have. No one here is really that bothered about what you ride.

+1

Welcome to the mayhem :-)

Tighten up the saddle, and get a smaller sprocket since youre in deep south to head brixton cycles.
yeehaa
Stoopsombitch!

about 1/3 of the forum have owned a langster at some point, including me. Don't mistake the self-hate for hate :-)

The standard chainset with the langster is the Sugino messenger, with 130 BCD and a 1/8" chain (there are two sizes, 1/8" and 3/32"). If you buy a new cog, you'll need to ensure that it's 1/8".

Adding or removing teeth to your drivechain at front or back and keeping same chain length will move your rear axle back/forward by 1/8 inch per tooth added or removed.

Depending on where the axle is sitting in the dropout you might need to lengthen or buy a new chain as you would be moving axle 1/2 inch forward by adding 4 teeth at front.