Tyre Size

[The Kid]

Hi,
Need to pick someone's brains.

I've been offered a spare wheel cover for my rear mounted spare but am not sure it will fit and I can't physically check it as it's too far away.

Apparently it carried a 255/80/15 wheel but was a bit too big for that.

My spare wheel/tyre is 275/60/15 and although I know the 15 is the wheel size I have no idea what the other 2 measurements are.

So, my questions are - what do 275 & 60 relate to and is my wheel going to fit in it?

Thanks in advance,
Ken

[Antshiel]

Apparently, unless i'm mistaken, 275 is the width of the tyre and 60 means the sidewall of the tyre is 60% of the overall width. That tyre size should go on the rim too.

[nero279]

Apparently, unless i'm mistaken, 275 is the width of the tyre and 60 means the sidewall of the tyre is 60% of the overall width. That tyre size should go on the rim too.

correct,

255/80R15 means width = 255mm, height = ((255*80/100)*2) + (15*25.4)=789mm

width * profile ratio
top & bottom
wheel diameter in mm

275/60R15 means width = 275mm, height = ((275*60/100) * 2) + 381 = 711 mm

[The Kid]

Many thanks Antshiel & Nero.
I'll go for it then.
Ken