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Having had some frustrating, sticky experiences with other fat-body or hose-equipped pumps we approached the Big Bore with doubts. Best gravel tyres: from dusty to dirty, here's our pick of the best tyres for your gravel bike.Oversized press-on Schrader and Presta head won't accidentally remove valve cores and can be easily used with thick gloves. 12 best gravel bikes for racing and exploring off road Designed for Fat and Semi Fat tire bikes, the Air Tool Big Bore Pump packs massive volume-per-stroke, and it features a head that still works with winter gloves on to make it perfect for backcountry winter fat biking.The fact the two halves twist-lock together when not in use means the shaft is more likely to stay clean which is crucial with large-bore pumps where there’s already more seal drag and a bit of grit can lock them solid.
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As long as the tyre is properly popped into place that’s enough for all MTB and most gravel purposes though and there are plenty of high-pressure options in the Air Tool family. The large stroke volume means you’ll have to work hard to get up to 30psi and you’ll be risking the veins in your temple getting close to Specialized’s claimed 50psi. It’ll obviously top-up conventional or pre-seated tyres quickly and easily too, so if you’re running fat rubber it’s awesome.