Singlespeed & Fixed Gear - Swapping cogs vs swapping chainrings

I have a fixed-free Formula hub so if I want to change the gearing by changing cogs it's this whole ordeal to get the lockring and cog off (I would imagine. I have not done this yet..) Plus DA cogs are not cheap ($26). It seems like a much easier proposition to swap chainrings instead. It's quick and easy to get chainring bolts off and chainrings can be had for cheap.

Just in case though, I thought I would ask: Is there anything wrong with swapping chainrings instead of cogs?

I've been kind of going through this dillema myself. I think it's actually cheaper to swap cogs. you'd be hard pressed to fine a $26 track chainring. that is, unless you're using a 3/32" chain in which case you probably have a bunch of chainrings lying around already.

If you have a lockring tool then it's a piece of cake to change your cog. you can just do a reverse rotafixa to get it off. or if you're chummy with your LBS just make them do it for you (or show you how).

Good quality cogs are much cheaper than quality rings.

Good quality cogs are much cheaper than quality rings.
true story.

you'll also likely need to add and subtract links to your chain, if you want any significant gear change.

it takes two to three teeth on the ring to achieve the equivalent of one tooth on your cog.

I'd be going from 42x16 to 46x16. The chain and cog are 3/32" so I was thinking of getting one of these (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ih=004&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=140087207620&rd=1&rd=1).

Edit: Also I can't really go down to a 15t cog since that is not enough, and a 14t cog is too much. 46 seems like the sweespot since it is halfway between 42 and 53 (which I both have) so with only one chainring purchase I have all the gearing I will want to play with for a long time, all without buying new cogs.

sounds like you've got it planned out pretty well

Good quality cogs are much cheaper than quality rings.
Which has always confused me. There's a lot more work and machining (usually more expensive than the material itself) that goes into making a cog.

Chainring: Stamp out of plate

Cog: forge (?) and cut threads

Mac

I would suggest that you actually try both methods. Keep in mind that to change a chainring and make sure that the chainring bolts are on tight enough you need to remove the crank as well. To me it seems like too much additional effort (to change the chainring) to gain an additional 2 gear inches

42x16 -> 46x16 is a gain of ~6.7 gear inches, not 2 (says http://www.panix.com/~jbarrm/cycal/cycal.30f.html)

I don't see the need to remove the crank to get the bolts on tight.

Anyways, I bit the bullet and bought a 46 ring. Thanks for the advice.

report back

Since we are on the topic and I don't see the need to start another thread...
1) I'm after a 130bcd,48t,3/32", chainring in silver (high shine/polished) that has cutouts in it. I know I can get a Salsa or Surly, but those are solid (without cutouts). Point me towards one if you know of one.

2) I'm after a 3/32", 17t, silver cog. Does EAI make one in this size in silver? I know they make black. I know I can get a Phil Wood, Shimano DA, Surly or others in this size and tooth count and color.

Thanks for the leads.

I don't see the need to remove the crank to get the bolts on tight.

agreed

a quality cog is cheaper than a quality chainring, but the bad possibilities of using a less-than-quality chainring are way less than the bad possibilities of using a cheap cog. pretty much the worst you're dealing with when it comes to cheaper chainrings is a little bit out of roundness, which is fine for many people. a bad cog on the other hand will chew up your threads.

anyway, sac02, manufacturing a chainring is a little bit more complex than stamping out a plate, especially for the high end stuff that costs more than your house. maybe 11.4 will weigh in?

get a 47 tooth ring. prime number = more skid patches. 47x17 is great for ny winter, 47x16 is great for ny summer.

This is a very viable setup, much nicer to your hub threads. Just get 2 different chains.

What tool can you use on chainring bolts with the crank off the bike that you can't use with them on it?

I'd also say you should replace the cog. Lockrings go on & off quite easily, with the proper tool.
And, you know how cool it looks to have a huge chainring...

Since we are on the topic and I don't see the need to start another thread...
1) I'm after a 130bcd,48t,3/32", chainring in silver (high shine/polished) that has cutouts in it.


Stronglight and Specilities TA both offer 130 bcd, non-solid rings. TA one is more a dull grey (but nice though). Can get 'em from http://www.businesscycles.com/trcomp.htm#chainrings etc



2) I'm after a 3/32", 17t, silver cog. Does EAI make one in this size in silver?


EAI make their alloy cogs in 3/32", silver and 17T - wouldn't suggest 'em for the street though. Superstars (the really shiny silver EAI cogs) are only 1/8".