I have a run of the mill Serfas pump. It has worked flawlessly for well over 2 years. Not a single problem for $30-35. Then, I decided to upgrade to Blackburn Airtower 5. The head does not fit that well on valve extenders. At least some of the Zipp ones. They tend to leak. They do seem to have a higher volume per down stroke, but who cares if it leaks!!
I just wished I had the 20 year old Silca pump I threw away a few years back during a move!!!
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