junkyardking

I posted this over in CX as well, but figured maybe some of the 'cool kids' over in this forum could offer some insight. Thanks in advance.

I'm looking to build up a SSCX frame to race with a little at the end of this season, but also to use for some single track riding and 'round town commuting. UK manufacturer On-One has a model I like (Il Pompino) for fairly cheap, so I'll be building one of those up with a variety of components.

I'm wondering what those of you who have SSCX bikes like as far as gear ratios are concerned. I've read that 39/16 and 39/17 are popular combos, but I can't find many chainrings that are single speed specific and only 39 t. It seems like 42 T is the minimum most companies manufacture. I looked at Surly's steel chainrings, and while they seem pretty decent, they are also a bit more than I want to spend. MSRP on my crankset is $100, so I'd feel sort of silly shelling out nearly half of what the crankset is worth on a chainring, especially when I know that there are decent $20 models out there. Could I just use a 39 T chainring designed to be the middle ring for a triple crank, or will I run into problems if it isn't SS specific?

Also, does anyone have advice on how to get a nice, pretty, straight chainline?

adriano 

youll be getting an inner chainring so theyll all be flat and good to go.

adriano 

ie https://www.google.com/products/catal...ed=0CHEQ8wIwAQ

Dcv

If you use a chainring from a geared bike you may want to use a 3/32 chain. If you use a track ring you might have to get a 1/8 chain, just make sure your cog matches the chain ring.

As for chainline do you gave a crankset or rear hub/wheel yet? Most track parts have 42 mm chainline. A standard road double crankset / ENO hub will have around 47 mm chainline. if you have a square taper BB you can pick an axle width to get the chainline to match your hub.

I ride 38x15 fixed gear for commuting, 38x17 single speed for off road riding.

junkyardking

The hub is an IRO track hub. Standard track spacing, 42mm chainline. The crankset is a Sram track. It comes with a 48t chainring that I'll be replacing, and goes with a square taper BB. The BB was thrown in for free when I bought the crankset online, but they didn't tell me how wide the axle was, just that it's English square taper. What width axle matches a standard track hub?

mikeetow

if you are doing a singlespeed cross, don't get track stuff you are better off using a standard wheel with an SS kit so you can adjust chain line an gearing.

FKMTB07

Salsa makes sub-42t single speed chainrings.

Dcv

sorry i don't know, i thought SRAM cranksets were GXP bb's? did you try looking through SRAM website or online dealers?

junkyardking

We're both wrong. I wasn't paying attention when I posted, but this particular crankset comes with a Truvativ (still Sram, technically) powerspline BB. So although is isn't square taper, it still has a spindle since it isn't outboard bearing.