Am I an idiot if I don’t use a wide base single-speed cog – will a standard one chew up the freehub body?

(such as http://www.superstarcomponents.com/en/wide-base-steel-sprocket.htm)

Also, anywhere to get cheap and simple single-speed spacers?

Ta,
Duane.

Yes, the standard one will chew up a free hub – look at what it does to cheap cassettes as a guide. However a widebody one works perfectly

Also worth looking at getting one of the stainless steel freehub bodies.
I’ve ran mine singlespeed for ages and it hasn’t got a mark on it yet.

Also, anywhere to get cheap and simple single-speed spacers?

Here you go…

Superstar