On this morning’s MadLibs ride, I had a chat about wheel & tire widths with a couple of other riders. It’s good food for thought, so I thought I would pass this along.
The old school of thought was that thinner tires cut through the air better, and offered less wind resistance. Notice, that is “wind” resistance. Riders racing on skinny tires would pump them up rock hard, then race off. The ride was bumpy, and definitely uncomfortable.
Today’s pro riders often opt for a 25 mm tire and using the same tire pressure that they would run in a 23mm tire (pressure may vary based on conditions). The 25mm tire has less rolling resistance because of the contact patch — where the rubber literally meets the road — is smaller than a 23 or 21 mm tire. A 25mm tire contact patch is wider, but shorter than the slimmer, longer contact patch of a narrow tire. This handy diagram from Continental breaks it all down.
Who wouldn’t want a tire that rolls better, faster, and with less resistance. Plus, fatter tires are much more comfy for bumpy roads and can handle gravel pretty well too. You might want to make sure your frame can accommodate a bigger tire than what you are currently running; some aero road frames and time trial frames may have trouble. Also keep in mind that may need to adjust your brakes if you change your wheels as well. Also, it is a little known fact that it’s easier to ride a straight line on wider tires, and that is something every triathlete should be excited about.
h/t to Competitive Cyclist: http://www.competitivecyclist.com/learn/25-vs-23
Also read this piece from Peloton Mag: http://pelotonmagazine.com/chatter/wolf-vorm-walde/