the yellow indicates to me you may be using polyester resin then,as oppossed to epoxy which is the proper stuff for carbon.not being nasty but if it is polyester its a lot more brittle and will be more liable to allow uv degradation over time.unless you are topcoating them with something like p.u varnish to block the uv of course.

Definately using epoxy resin. The hardner is where the yellow tint comes from.

what make epoxy is it ,as i have got 5 litres of west systems but havent started with it yet and assumed its gonna be clear.

Its also the west system epoxy resin 105 with 207 hardner and i have the 205 hardner. Got some different epoxy and hardner also that i have yet to try out.