Sprockets all the same?

stupid newbie question,

I've pretty much got all the bits for me first fixed, just need to get me wheels built and to attach all the bits to the frame.
BUT...

I don't actually have a rear sprocket yet, now I'm assuming that any rear sprocket (EAI, Phil Woods, Condor) will work on any fixed rear hub. Got my eye on a soma 1/8th one to fit a phil wood fixed rear. But is that correct. The threading on a fixed rear isn't proprietary like say a french or italian bottom bracket, is it?

Many thanks for your advice, knowledge, views...

all the same. if you spent £'s on phil woods, i wouldn't skimp on a cog. don't know of soma's, but surly are pretty sturdy and costly though (too much some say). same deal with lockrings (check it is a rim lockring, not BB one, hey mouse :p )

Phils should come with the lockring/s anyway. Why not just plump for the Phil cog too? Shiny shiny shiny.

Corny, they are not all the same, get an EAI, on there....also give me a ring

I thought there was some issue to do with the type of threads, which made EAI cogs slightly different to Dura-Ace. I don't think it was a major problem, but did mean that swapping between different manufacturers' cogs on the same hub could 're-cut' the threads a bit...? I'll see if I can find a link somewhere.

They are all similar but are not the same. There are Italian and English standards and they are close enough that they are interchangeable. However, mismatching the cog/hub (e.g. Dura Ace sprocket (English) on Campy hub(Italian)) slightly damages the threads. This isn't a problem in itself, but if you then put an Italian threaded cog on there then there is a greater chance of stripping the hub.

In addition, all the manufacturers tolerances vary a bit which can lead to the same problem.

The best practice is to stick to one manufacturer if possible to be absolutely safe. I use a cpmbo of DA, EAI and Surly cogs on my bikes and so far all is good. However, if I had just bought some new Phil hubs then I would probably stick with Phil cogs to be as safe as possible.

Lockrings are a whole different ball game. Here the standards are significantly different. I think Phil uses Italian lockrings so it's Capy or Phil for you. Again, I'd go Phil as I've heard that Campy ones are a bit shit.

Some stats:

Type Thread Equivalent
I.S.O. 1.375" x 24 tpi 34.92 x 1.048 mm
British 1.370" x 24 tpi 34.80 x 1.058 mm
French 34.7 x 1 mm 1.366" x 25.4 tpi
Italian 35 mm x 24 tpi 1.378" x 1.058 mm

Having said that, I've swapped between EAI, On-One, and Tranzmission (cheapoid) sprockets on my System-Ex hub without problems (but I'm careful not to go mental tightening it up with a chainwhip in the first place).

benanza Phils should come with the lockring/s anyway. Why not just plump for the Phil cog too? Shiny shiny shiny.

they don't stay shiny for long though but still i would go with benanza's suggestion

cool, phil it is...

I didn't want to spend excessively on the bike, but the budget and the cost have spiralled so I'm trying to bring it back under control, hence the decision to buy a soma sprocket.

anyone got a 1/8th 16t phil wood sprocket lying around they want to get rid of???

funny how we all do that. watch the cost spiral out of control and then try and reel it in a bit on like cheap bartape or something. can't help with you a spare 16t sprocket. or the 30 notes you will need for buying one. good luck with completing the build

i have about 7 different EAI cogs and i love them. everyone i know who uses EAI swears by them.

All cogs are created equal, but some cogs are more equal than others.

you see the world via a fixed sprocket, how poetic.

lpg All cogs are created equal, but some cogs are more equal than others.

two wheels good four wheels bad

also cogs have different spacings i use an eai cog as it's chainline is further out than some other cogs which helps my chainline. there is a chart on sheldon brown that lists the differences.

MrSmith also cogs have different spacings i use an eai cog as it's chainline is further out than some other cogs which helps my chainline. there is a chart on sheldon brown that lists the differences.

Glad you said that. I read something about someone on here needing a 2mm spacer for a flyer to correct the chainline. That gave me a minor panic until I looked again at mine again and realised that it is fine with an EAI.

is there a way of telling which sprocket I need for my hubs?

I bought a second hand fixed last summer and would like to put a smaller sprocket on but I can see no markings on the hubs, sprockets or lockrings to tell me what sprocket to buy

the rims are campag lambda but whether this makes the hubs italian I'm not sure, it's a double fixed/fixed hub

picture?

on it's way

hurry!

I can't seem to upload them, on here....

hmmm hubs i cant id, but i think a surly cog should work looks like the ones you got

ok thanks, much appreciated

i am basing this on looks like the one you have and absolutly nothing else... just to be clear

yes sure, I'll double check with the LBS before I part with any money on sprockets, thanks