Ye Olde Original SS inbred – which is my much abused but loved winter bike – is due a revamp and I am thinking of sticking some rigids on it to make it as maintenance free as poss, so what size rigid forks do I need? I am thinking of some On-one forks but am not fussy really.

400 – 420mm Pace RC31's?

I've got a pair of v/disk SIDS you could drop the travel on for a suitably retro noodley experience?

Thumbs up here for the OnOne carbon forks. The Pace forks are supposed to be more flexi, considering how much the OnOne's flex I don't think the Pace's sound that great.

On One carbon's get my vote as well.

Surly do some nice rigid blades, not carbon but solid and a good price.

I guess it all depends on whether you want a slacker or more steep head angle. I've used 390mm axle to crown BMX type forks and 410mm Kona jump forks and 440mm DMR trailblades (liked the handling with the Konas best).

Exotic do some reasonably price carbons, in all sorts of lenghts – full carbon, carbon legs, alu etc, they are also the same forks as nukeproof, white bros
29er carbon rock for £89

I ran mine with a set of Orange F8s, they didnt seem as heavy as the On Ones they replaced.