I have a set of Reba world cups, but the steerer is a bit short for a frame that I want to put them on. It is a carbon steerer tube, can replacements be put on? Cheers

yes, but its expensive, as its the crown steerer unit, all one piece.

Find a bit of dowel that fits neatly inside the steerer tightly. Epoxy this in, then lengthen the steerer using a length of alloy steerer (ask for an offcut in the classifieds). Should be good go then.

On a more serious note, carbon crown/steerer assembly is pretty expensive, might be better to buy a new set of WC (On-One have them super cheap just now) or some other forks and sell your current ones on.

http://www.on-one-shop.co.uk/acatalog/Online_Catalogue_Suspension_368.html – £249, good buy if you really feel you need the carbon crown/steerer.

Bargain to be honest, although I think I'd sooner have a 2009 SID.

The CSU assembly was about £400, not worth doing at all!