To inflate a Presta valve, you just unscrew the valve stem anti-clockwise and after that connect a pump. At the time the specified air stress has been attained, eliminate the pump and screw the valve stem clockwise to ensure it really is airtight. Some pumps, for example this Silca Gravelero, https://bookmarkunit.com/story19597443/how-much-you-need-to-expect-you-ll-pay-for-a-good-live-chat-support-prestashop