Originally Posted by
Sixty Fiver
Weight does play a small role as well but even then, the difference between a light weight racing tyre and a good commuter tyre may only be as much as half a bottle of water and as commuters usually carry more gear and aren't all lycra'd up wider can often be much better.
It's not just about how much weight there is, it's about where it is. It's one thing to just carry something in your backpack or pannier. And quite another to have it on the wheels. The extra pounds in your backpack just need to be propelled and accelerated forward. But the heavy tires need to be propelled and accelerated both linearly (forward) and angularly (around). So heavy wheels will affect your acceleration a lot more than a bottle of wine in your backpack. And how often do commuters need to accelerate? Well, it depends on where you ride, but I have about 20 stop signs and 25 traffic lights on my 7-mile one-way route to work... (And cheapo heavy wheels with kevlar-belted tires on my commuter.
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