Two people yesterday asked me for bicycle recommendations. Beyond the obvious--which to me is to test out bikes at two or more independent bike shops upon their recommendations--here's a few thoughts on bikes for the casual but serious bike rider who's interested in road riding, perhaps some on dirt roads. Can't comment on mountain bikes. Your comments welcome. I don't make much in the way of claims to extensive bike knowledge but have a few observations that I don't see elsewhere.
First, if you're over 40 like me and haven't had a bike for a while, there's a new category of bike which my friend who knows orders of magnitude more than me on the subject calls "lawyer bikes". Classic in this category is the Serotta bike that John Kerry rides--expensive, beautiful, intended for serious riding and club racing, but with a frame geometry and set-up that provides forgiveness to an older body. Trek has a whole line of such bikes, their Pilot series.
Another category of road bikes to consider is cyclocross. These are road bike type frames adapted to the sport of cyclocross, where people zip around a grass and dirt track featuring lots of hills and obstacles. But they're also great all-around bikes, perfect for commuting and dirt roads. The bikes have typical downswept handlebars but take their cantilever brakes from mountain bikes and have forks wide enough for knobbier, wider tires than road bikes. Bianchi makes a line of these, which includes a wonderful steel framed all purpose bike called the Volpe that's been around for years. The Volpe is the bike I own. Another entry level bike (and by that I mean about $800) is the Surley Cross-Check.
People who are returning to biking and are over 40 are usually thinking about a hybrid bike. Hybrids are the result of a union of mountain and road bikes, often resulting in a poor compromise, especially at the lower end of the price spectrum. They can't do real trail and off-road work like a mountain bike and they're slow on the road. But if you choose well, you could be quite happy for bike trail activity and casual commuting. There's some cool city bike variants too, like this one from Specialized that features an internal 8 speed hub and a front light driven off the friction of the wheel.
Singlespeeds are probably not a good choice for someone returning to biking, but depending upon the terrain you ride it might be great. There's an upsurge in such bikes, a good way to channel your desire for a more simple life and also connect to bike messenger culture! Here's a missive on singlespeeds from a crazy bike guy who owns a shop to visit if you live in Boston.
If you really want to return to your youth, you can buy a bike from the wonderful obsessives at Rivendell who created a mini-cult following for those who believe that bike technology reached a plateau sometime before index shifting. (For those who don't know, index-shifting is a technology now found on essentially every bike but Rivendells that let's you shift with discrete click stops between gears instead of feeling your way through the gears via a friction gear shifting system.) I'd buy a Rivendell if I could, especially with their psychedelic SpeedBlend tires.