Originally Posted by
chephy
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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It is called rotating weight and I understand the concept... would never tell you that my touring bike with it's 26 by 1.5 Marathon's could ever accellerate as fast as my P20 folder with it's 406 Comet Primos and even my road bike would be hard pressed to match the pickup you get off such light and aerodynamic wheels.
But there is always a trade off between weight, ride, and durability and I think we're still in the commuter forum where weight weenies usually fear to tread.
Got to playing with my Trek this afternoon and besides the 700:45 up front I now have a 700:38 Avocet Cross tire in the rear and just came in from doing some road testing on the hard pack and in some deep patches of snow.
Have to give the ride an A+ and the combination of the wider and knobbier front tyre with a slightly slicker but still grippy tyre in the back makes the Trek pile through snow better then my 26 inch wheeled winter bike as it digs in a little deeper and floats less.
And once you get those slightly heavier (and probably tougher) tyres up to speed they like to maintain that inertia.
Have taken my touring bike out on faster paced rides and had friends struggle to keep up with me as after you get past the weight of the Marathons, they roll out pretty fast.