Tyre pressure

ripper said:

Got my son a 20" BMX bike for Xmas. Nowhere in the manual does it say what the tyre pressures
should be. Can anyone advise?

Look carefully around the sidewall of the tire; the max pressure rating should be printed or
embossed somewhere (although it may not be easy to see).

If it really isn't on the tire, try about 40 psi.

Art Harris

ripper said:

Got my son a 20" BMX bike for Xmas. Nowhere in the manual does it say what the tyre pressures
should be. Can anyone advise?

Look on the tire sidewall. Most are 60psi but some 20" now go to road (100psi+) pressures.

It's also prudent to spin the wheel and ensure the tire's on straight before airing to
full pressure.
--
Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971

ripper said:

Got my son a 20" BMX bike for Xmas. Nowhere in the manual does it say what the tyre pressures
should be. Can anyone advise? TIA

40 psi is normal for mountain bikes - if he does crazy stuff on it you might want a bit more to
ensure the rims never bottom out on the road.

Quoted message said:

Look on the tire sidewall. Most are 60psi but some 20" now go to road (100psi+) pressures.

Unless it's got cheap plastic wheels. You've never had a mechanic explode a tire off a rim by
running "rated" pressure on one of those? Given enough time, I think it happens to most mechanics...
but the good one, only once!

--Mike-- Chain Reaction Bicycles chainreactionbicycles.comchainreactionbicycles.comOpen ↗

Mike Jacoubowsky said:

Quoted message said:

Look on the tire sidewall. Most are 60psi but some 20" now go to road (100psi+) pressures.

Unless it's got cheap plastic wheels. You've never had a mechanic explode a tire off a rim by
running "rated" pressure on one of those? Given enough time, I think it happens to most
mechanics... but the good one, only once!

My 47-406 Tioga Comp Pool slicks have a recommended inflation pressure range of 30-90 psi for
"spoked wheels" and 30-45 psi for "plastic wheels".

Tom Sherman – Close to 41½ N, 90½ W

Mike Jacoubowsky quoted:

Quoted message said:

Quoted message said:

Look on the tire sidewall. Most are 60psi but some 20" now go to road (100psi+) pressures.

and said:

Unless it's got cheap plastic wheels. You've never had a mechanic explode a tire off a rim by
running "rated" pressure on one of those? Given enough time, I think it happens to most
mechanics... but the good one, only once!

Right. The pressure markings on the sides of tires are generally just about useless. I address this
topic in some detail at:

sheldonbrown.comtires.htmlOpen ↗

or

sheldonbrown.comtyres.htmlOpen ↗

However, for kids' BMX bikes, I suggest making the tires feel about as hard as a tennis ball.

Sheldon "There's A Hard Way And An Easy Way" Brown +-------------------------------------------+
| Any smoothly functioning technology | will have the appearance of magic. | --Arthur C. Clarke |
+-------------------------------------------+ Harris Cyclery, West Newton, Massachusetts Phone 617-244-
9772 FAX 617-244-1041 harriscyclery.comharriscyclery.comOpen ↗ Hard-to-find parts shipped Worldwide
captainbike.comcaptainbike.comOpen ↗ sheldonbrown.comsheldonbrown.comOpen ↗

(am)>>Look on the tire sidewall. Most are 60psi but some 20" now

Quoted message said:

Quoted message said:

go to road (100psi+) pressures.

Mike Jacoubowsky said:

Unless it's got cheap plastic wheels. You've never had a mechanic explode a tire off a rim by
running "rated" pressure on one of those? Given enough time, I think it happens to most
mechanics... but the good one, only once!

Plastic 'mags'? Are they still selling those? Yes, those are just horrible- with all the
disadvantages rolled into one product - heavy, prone to cracks, random bead seat diameter and you
cannot repair them. And the bearings stink, too.

I'm with Mike - not only should you not air those past 35-40 psi but, if it has plastic mags, I'd
try to find the receipt and exchange it for a bicycle.
--
Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971