My question is one of weight... I am roughly 15 and a half stone and feel that I am much too heavy for road bikes (ie, wheels narrower than the 35mm I have on my Giant hybrid). I only ride about 20 miles but would like to go for day-long rides of 40-60 miles but do not want to spend money on a road bike only to find out I was right about my weight.
Philip Brown, email
A: Weighing 15 and a half stone (98kg) certainly doesn't make you too heavy for a road bike. Magnus Backstedt has had a long and successful career, including a stage win in the Tour de France and, at 94kg, he's no lightweight. I'm heavier still, at 105kg, but I exclusively ride skinny-tyred machines on the road: a Pedal Force running 700x23 tyres for time trialling; and a 700x26-equipped flat-barred machine for everything else, including longer rides up to 100 miles.
A good road bike will revolutionise your riding. It'll be so much lighter, faster and slicker than your hybrid that you'll wonder why you didn't buy one years ago!
It's important to select the right equipment, whatever shape you are. If your concern is that you might break a road bike, then choose something nice and solid. A stiff, mid-range aluminium frame is a better starting point than a feathery and flexy high-end carbon machine. A frame weight of around 1.5kg is light enough, and there are plenty of excellent options - check out the Specialized Allez or Trek SL1000.
A carbon fork is a definite advantage, but I'd choose aluminium over carbon when it comes to stem, seatpost and bars. A sturdy double clamp seatpost is a good upgrade, and make sure there's plenty of seatpost in the frame - the seat tube junction is a likely place for the frame to fail. You may prefer to opt for traditional 32-spoke wheelsets, though I've used plenty of lesser-spoked offerings (Fulcrum Racing 3, Rolf Vector, Shimano Ultegra) with no problems.
Fitting some slightly bigger lightweight tyres gives the benefit of a larger air chamber to soak up the bumps without affecting rolling weight too much. I'd recommend a 700x26 - Soma's New Express Kevlar is excellent, if a little expensive. Carrying that extra body weight costs you most on the hills, so make sure you're packing a triple chainset, or at least a compact and a wide cassette.