Following on from yesterday's question about repairing valves, more advice needed. Are all 20" tires and tubes created equal? Will a 20" BMX tube fit the wheels on a 20" Islabike?
There's different widths, just get the one that matches your tyre. You can get away with a bit over or under if you need to. There's a few different valves. You probably want schrader
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Do you know if 20" kids MTB is the same as 20 BMX, and 20" Brompton style?
Some kids ones have woods valves not sure why. No reason not to 'upgrade' schrader. I suspect a brompton's will be skinnier, aren't they 16" anyway? Generally a tubes a tube, especially at this end of the market.
Not all 20" tyres/tubes are the same 20", will depend on if the width has a decimal point or a fraction in it's measurement, as to what it's ERTRO number(and thus fit's fitting size)will be.A 20x1.5 will be impossible to fit if the original was 20x11/2 as far as tyres go, though you may be able to force a tube to fit.