Q: I have had a plague of punctures recently, even flints cutting through the tread and carcass! So I may have found a best buy from Halfords – a Continental tyre with tube at £20 with a year's guarantee against any air loss and free replacement if the worst happens. However, the tubes are fitted with Presta valves, not the reliable and easily inflated (I use a pump run from the car) Schrader valves. Why the difference and where can I buy a pressure gauge for the Presta valves?
A: It's down to weight, Tim: Presta valves are lighter than Schrader. The Topeak Smarthead pressure gauge costs £17.99 and connects to both Schrader and Presta valves, has a digital display and weighs just 95g, though I'd recommend getting a track pump instead as they're more efficient and far easier to use than a handpump, and most have a built-in gauge. The Topeak Joe Blow Max 2 track pump costs a very reasonable £19.99, given that it has a hard-wearing steel body and a gauge.
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