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Newbie tire question(5 posts)

Newbie tire questionlemmy999
May 12, 2002 6:49 AM
I am new to road biking. Can someone tell me the negatives of going to a smaller width tire? Thanks.
re: Newbie tire questionMe Dot Org
May 12, 2002 9:16 AM
The greater the contact patch (wider tire) the more stable your bike will feel. There are also some ride quality benefits.

The downside of a wider patch is more rolling resistance. Everyone picks a compromise point with which they are happy. My subjective ratings:

20c: For racing

23c: Probably the most popular road tire width. Good for training.

25c: A little more secure/comfortable than 23c. If you feel beat up after a long ride on 23c, these might be a solution. At the light end of possible 'credit card touring' tires.

28c: Light to medium touring or grocery bike, dirt/off road.

+28c: Touring or dirt/off road use.

Again, these are my subjective impressions. Your results may vary.
re: Newbie tire questionweiwentg
May 12, 2002 10:50 AM
to add to that, there is some debate on this topic, but most people agree that 20c tires have more rolling resistance than 23c tires when inflation pressure is identical. since I got my tires cheap on closeout, I race and train on 20c tires, and I have survived the experience. most pro cyclists race on 23c tires (if they're on clinchers).
Rolling resistance proportional to tire pressureKerry
May 12, 2002 1:33 PM
Rolling resistance is largely caused by casing deflection, and a smaller tire will have to deflect more to create a given tire footprint. Tire footprint is a function of rider weight and tire pressure (200 lbs of bike plus rider with 100 psi in the tires = 2 square inches of footprint, regardless of tire size). Smaller tires typically allow higher pressures, and so can have smaller footprints. The downside to the higher pressure is a harsher ride and poorer traction on rough surfaces. 23 is typically a good size for most riders, with 25 or even 28 for the "mass enhanced." Small riders can get by with 20s.
Yep--don't automatically go for the skinniest tirecory
May 13, 2002 7:35 AM
Maybe it's because I'm a Clydesdale, but I think many riders overestimate the advantages and underestimate the disadvantages of skinny tires. Kerry's right about contact patches (footprints), and the stability and comfort of a larger tire is pretty nice to have at the end of a long ride. I do most of my Just Riding Along on 700x35s, and rarely use anything smaller than 32 (they're usually only about 25mm wide anyway).