Dear Matt,
As a recently retired wrinkly, I want to take up cycling again after a 40-year gap. I went to the Cycle Show, with thoughts of spending lots of money on a new lightweight bike. Mmm, things have changed a bit. Can you tell me why all the frames now look as if they're too small for a normal-sized adult? And why is the crossbar no longer parallel to the ground? I want a bike for fitness riding on the road; any suggestions would be helpful. Mike Whittaker, via email

Yes, things changed - chiefly thanks to inventor Mike Burrows (designer of Chris Boardman's Lotus bike for the 1992 Barcelona Olympics). Then working for Giant, he realised he could save weight and make a stiffer frame with a sloping top tube. Hence the "compact" frame.

But there are still plenty of "old-fashioned", conventional diamond frames around. Personally, I prefer the traditional look, but there is no doubting the efficiency of compact designs. And if you can get used to the appearance, you will be impressed by the performance.

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