Simple question about tyre sizes

Hi All,

A car I've just bought has the following tyre size...

30 X 9.5 R15

What would this size be using the normal measurement? (e.g.235/75 15)

9.5 - is that inches width?? Approx 235mm?

R15 - diameter in inches.

What is the 30 for? Presumably it must relate to the profile?

Thanks,

Martin.

Reply to
Martin
Loading thread data ...

A 4x4 presumable.

Pretty sure this is a different standard of tyre size which doesn't equate exactly to a size in the conventional format.

Lots of 4 wheel drives use this inch based notation.

Reply to
Doug

The 15 is the rim diameter, R is the speed rating.

It could be the tread diameter, but I haven't come across this notation.

Reply to
Richard Porter

IIRC it's the US way of indicating tyre sizes, in inches. I believe the 30 indicates the overall diameter of the tyre. 9.5 probably indicates the width. Measurement in inches.

Ask the question in alt.fan.landrover, the answer will definitly be forthcoming as a lot of off-road tyres come from the US market, and are so marked.

Alex

Reply to
Alex

Closest would be 245/75 R15

Reply to
chris

Hi,

Thanks for all the replies. Makes perfect sense.

The tyres are on a kit car incidentally.

Cheers,

Martin.

Reply to
Martin

It's a 4x4 tyre size. The 30 is the diameter of the wheel in inches. 9.5 is the width of the tyre in inches. When I had a 4x4 I used to fit

31x10.50 R15s which is a common size in large 4x4s.
Reply to
Chris Bolus

Not quite

30inch is the rolling diameter of the TYRE 9.5 inch is the width of the tyre tread incontact with the road. R is the speed rating. 15 inch is the wheel rim diameter

Normally tyres marked in this manner with inch sizes are X ply or bias belted.

Reply to
dilbert

oops, that's what I meant to say!

>
Reply to
Chris Bolus

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.