Wheel, tube and tyre sizing? I'm confused!

[d3v]

Hi all, I just picked up a kids BMX that is is pretty bad shape but I'm currently renovating it to give to my young nephew and while everything is going smoothly I am just confused about what sized tyres and inner tubes I need for the wheels.

This bike came with no tyres or inner tubes and there is no marking on the rims either, so I'm at a loss as to exactly what sizes tubes and tyres I need.

I measured the width of the rim at it's roughly 16 inches, so how would I now translate that measurement into knowing what size tyre and inner tube this wheel needs?

Thanks in advance!

[GeorgeET]

Sounds like 16" diameter wheel so:


http://www.amazon.com/s/?ie=UTF8&keywords=16+inch+bicycle+tires&tag=googhydr-20&index=aps&hvadid=22741939067&hvpos=1t3&hvexid=&hvnetw=g&hvrand=21091767131185221634&hvpone=&hvptwo=&hvqmt=b&ref=pd_sl_9ltpp5zgdg_b

[d3v]

Thanks but I cannot seem to find a 16" x 2.35 wide tire anywhere in the UK!

[Bill]

Not sure about prices but I see this place mentioned sometimes on here
Www://halfords.com which I guess is a big place over your way .

[d3v]

AM I correct in thinking I need 20 inch tires even though the rim measured 16 inch across?

[GeorgeET]

(08-08-2012, 10:16 AM)d3v Wrote:  AM I correct in thinking I need 20 inch tires even though the rim measured 16 inch across?

NO..........

[nfmisso]

d3v - measure the bead seat diameter

http://sheldonbrown.com/rim-sizing.html

you can use a tape measure to get the bead seat circumference more easily that measuring the diameter. Then use the chart in the above link to figure out the ISO diameter of the tires you need.

I suspect you need ISO 406 - but measure. (measure twice, cut once.....)

[GeorgeET]

Boy Nigel now I too am confused. 406 mm = 16 inches diameter, but a 20 inch tire is listed?? There are 16" tires too.

I just measured my rims and the road bike is 25"D and takes a 26 tire and my MB is 23"D and takes a 26. I guess it aint inches.

[nfmisso]

Safest is to measure the circumference of the bead seat - the part of the rim that the inner most part of the tire sits against - see picture in the link above.

The outer diameter of the rim is not reliable because it can vary quite a bit.

26" tires are especially confusing
* ISO 559 - MTB tires typically sold as 26 x 1.95 or similar decimal nomenclature.
* ISO 571 - 650c
* ISO 584 - 650b
* ISO 590 - the English 3 speed size, sold as 26 x 1 3/8 or similar fractional nomenclature.
* ISO 597 - Schwinn S-6 26 x 1 3/8

It is safest to use the ISO size to be sure to get tires that fit.

http://sheldonbrown.com/harris/tires/597.html
http://sheldonbrown.com/tire-sizing.html

[GeorgeET]

Man , bicycle tires are more complicated than motorcycle or car tires, shees... There if it says 15" it is 15"...........

[nfmisso]

(08-08-2012, 10:14 PM)GeorgeET Wrote:  Man , bicycle tires are more complicated than motorcycle or car tires, shees... There if it says 15" it is 15"...........

Motorcycle, automobile and truck tires all measured by the bead seat diameter - like bicycle tires should be and are not (yet...) which is why I am really on the ISO sizing band wagon.

[d3v]

nfmisso that post a couple above was utterly mind numbing and I have no intention of wanting to know what any of it means, haha! Yesterday I found a kid on a BMX and asked him what size tyres he used becuase his wheels looked the same size of mine and he said 20 x 2.20 so I checked on ebay and bingo - http://www.ebay.co.uk/itm/220858638908?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Now I just need to know what sized inner tubes I need!

[nfmisso]

(08-10-2012, 05:29 AM)d3v Wrote:  nfmisso that post a couple above was utterly mind numbing and I have no intention of wanting to know what any of it means, haha! Yesterday I found a kid on a BMX and asked him what size tyres he used becuase his wheels looked the same size of mine and he said 20 x 2.20 so I checked on ebay and bingo - http://www.ebay.co.uk/itm/220858638908?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Now I just need to know what sized inner tubes I need!

I hope that you lucked out, they are the same size.

[d3v]

I ended up not buying them and instead am waiting on an auction for a pair of these tires plus a pair of matching inner tubes, so that will save me having to hunt down the inners, too! Will let you guys know if they fit!

[d3v]

I won it! http://www.ebay.co.uk/itm/290758341542?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

I had to also order a new headset, new bottom bracket and new rear singlespeed freewheel, so spent about £50 in all, but also need new hand grips, brakes and brake levers and to replace the bearings/cones on the rear wheel but I have these things lying around thankfully.