I carry both, in large part because I commute. There are days when the least amount of time spent repairing a flat the better. When I have time or the weather is better, I use the pump.
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A conclusion is the place where you got tired of thinking. - S. Wright
Favorite rides in the stable: Indy Fab CJ Ti - Colnago MXL - S-Works Roubaix - Habanero Team Issue - Jamis Eclipse carbon/831