Well I think that the headset is GB at least the stem is. I'm not too great on bike terminology and quite what component/component set the head set comprises of but certainly the stem is GB.

I've taken apart the bottom bracket and I found some markings on the spindle. One looks like an R but I can't identify what make it could be? I can't work out the other marking:



Also on The pedals and hubs they're marked with a 'u' symbol with 'made in germany' stamped on them as well do you know what manufacturers mark that might be?

thanks