OT: WFT was THAT !

[PeterC]

There are two major causes apart from that: the old valves had a nut and there was enough room for the weakened rubber to expand out. Had one go at about 3 am when I was asleep (yes, the bike was in my bedroom). The hole in the rim is made for Schrader; a washer or adaptor is needed.

The Presta is easier to pump up as it's effectively free to move and is of smaller area. I've used Presta for about 40 years and 400,000 miles and the memories of Woods and the odd Schrader still recur occasionally.

My 700Cx25 tyres are happy at 100 psi but would take 110.

[Jethro_uk]

Feel free to try it ... stop when you smell burning.

[Nightjar]

I had a compressor and reservoir in my factory that was capable of 11 bar (160 psi), although the compressor cut-off was set at 7 bar (100 psi), as nothing needed the higher pressure and there was no point in wasting money achieving it. That was a 3 phase machine, but there was a single phase version available.

I suspect you would have a very long wait for it to get to the claimed pressure and the air would still be hot.

[harryagain]

Between five and ten psi.

[harryagain]

Reduced rolling resistance due to less hysterisis.

[Brian Gaff]

That does not sound right, I thought they were blowout proof these days, they cost enough for goodness sake!

Brian

[Dave W]

"struggles"? Are you sure your pressure gauge is accurate?

[John Williamson]

Depends on your physical strength and the pump diameter. That's why I use a 12 volt compressor if one's available.

I also use the Rule of Thumb to check the pressure on most tyres. If I can noticeably squeeze the tyre with my thumb, it's too soft. (Only works on 1 3/8" tyres or wider)

[Tim Lamb]

Somewhere between 8psi and 25:-)

[Tim+]

I'd be wary of using presta valves tubes in rims with a schrader sized hole. Would have thought that you'd risk tube herniation through the hole, especially at those sort of pressures.

Tim

[Tim+]

Tubes? Not that much (under £6 from Wiggle) and usually easily repairable.

Tim