I've a pompino II on order, the one with the 120mm spacing.
Never single speeded before, so Don't know much about set ups etc

For a start – What hubs? I don't want to go fixed, probably ever. Obviously I want cheap but not nasty, so cheap within reason.

What about the rear cog?

I think I need chain tugs too?

Also, what chains are recommended??

Oh, and What cranks?!

I should be able to decide on the rest of the gear myself 😳

Right, I'm doing much the same, but with an old holdsworth.

I'm having some wheels built – P-X track hubs, Sapim double butted spokes, Ambrosio Evo rims.

Freewheel – I'll be running mine fixed. If you want to go freewheel, then you'll need to source an appropriate one – no idea what's favoured these days, but they do tend to die.

Gearing – I'll start at around 70 inches, and go from there. Have a look at Sheldon Brown for gear inches table to give you an idea of chainring/sprocket sizes to get your ideal gear.

Crankset – check out the cheap Stronglight crank sets and BBs at P-X. I'll either go for 165s or 170s (I normally run 170s on my other bikes, and rather cheekily also do on my track bike…).

Chain – 3/32 if using road stuff. If you're using track kit, then 1/8. I'll go with whatever – SRAM probably.

Chain-tugs – not sure why you'd need them. Just do up the axle nuts tight enough.

Hubs – the on-one large flange trackhubs (£15 each end) are good value for money and build up well. The rear comes in 120mm OLN.

These are flip flop hubs, both sides having lockring threads as well. You can screw a normal SS freewheel on. I run mine at 49:18 at the moment, 49:16 fixed sometimes. Look for ACS Claw, shimano freewheel or if you have thee money for the best, Whites Industries freewheel (c.£70ish)

On-One/PX also have some nice 48T track cranks on sale for £50 w BB
http://www.planet-x-warehouse.co.uk/acatalog/Cranks_-_HALF_PRICE_SALE.html

Depending on where you live and ride, anything between 48:15 and 48:20 maybe appropriate?

The onone chain tugs are cheap and work fine. For added nicessness you may want to go for something like a surly tuggnut:

Chains – I favour SRAM PC1. Great value for money 1/8" chain.

Excellent advice lads, thanks.
I wasn't sure if the On-one hubs were fixed only or not.
I'll get some of them then and build them up on some cheap rims 🙂

I wasn't sure if the On-one hubs were fixed only or not.

They are. You just need to buy one of the freewheels recommended by Stoner.

to be fixed means it has to have an EXTRA set of threads (for the lockring), whereas to be free only needs the one set of threads (that are also used with a fixed sprocket)

see closely on here and you can see the two different thread diameters – the first takes a sprocket OR a freewheel, the second takes a lockring to hold a sprocket on, whereas its not necc for a freewheel

Stoner – gotcha. Only fixed bike I have is my track bike, and that naturally doesn't have a lockring.

My Pompino:
On-One chainset, 48T (square taper)
16T shimano freewheel and spocket
3/32 chain (I had spare)
Rear hub is a Mavic from about 20 years ago I had in the loft. Fits the 120mm spacing fine, I just needed to make up some spacers to ensure the chainline was right.

Been working well for at least 2 weeks!

My commuting machine is a road bike that has been fixed.
Therefore I only have it SS using a conversion kit from DMR or similar.
Gearing is 44/18 has I much prefer to spin and I have a nice bump on my way to the station.
I have ordered some on-one hub to be build into a nice set of wheels with dt spokes and mavic open pro rims.
I'll be running it fixed/ss. Probably 18 SS and 16 fixed.