David. Thanks for the reply. I am also questioning the original purpose of the frame! I took it on understanding that its a Paul Milnes 531 steel cx frame. It has all top tube routed cables and a top pull front mech, routed down the seat tube. So on face value looks like a cx frame. Last night I fitted the rear wheel with 35mm tyres and there wasnt enough clearance, I reckon a 28/32mm tyre would be the maximum. Maybe it isnt a cx frame after all. TBH what I thought would be a cheap build for a winter commuter is proving a bit of hassle. As the front mech is top pull it seems impossible to find a double top pull mech that will work with stis. Maybe a 1x8 might be the way forward. Charlie