Help understanding tyre sizes

chedixon · 10-13-2011, 03:09 AM

Hi all, ultimately i want to buy a pair of snow socks I've seen but they dont list the correct size for my tyres (255/30/19), they list a size of 245/35/19 and Another at 245/40/19.
The width of my tyres is bigger by 10 at 255 but as the height is only 30 should i add that extra 10 in width to the height thus going for the 245/40/19 option? Or is a tyre height/width relationship not that simple and the 245/35/19 will suffice, confusion reigns lol

Any help appreciated guys

B33M3R · 10-13-2011, 03:43 AM

I may be wrong but I thought the profile reference on a tyre ??/30/?? or ??/35/?? etc. was the profile represented as a percentage of the tyres actual width rather than a specific unit of height? So a 225/30/?? or 255/30/?? would have quite different profiles albeit with the same profile reference

Don't know if that assists

parapaul · 10-13-2011, 02:57 PM

He's right. The profile is a % of the width. I'd be reluctant to gamble on deliberately buying the wrong size - can you email the manufacturer and ask them? It's not as if BMWs are rare or unusual cars with wacky tyre sizes!

chedixon · 10-13-2011, 04:34 PM

Thanks guys, there from asda direct so I'll try them first, see if they can help, was just trying to get my head around it

rich1068 · 10-14-2011, 05:52 AM

Have a look here. There were some very useful links posted.

10-13-2011, 03:09 AM	#1
chedixon Lieutenant 63 Rep 438 Posts Drives: F82 YMB Coupe Join Date: Aug 2011 Location: Nottingham iTrader: (1)	Help understanding tyre sizes Hi all, ultimately i want to buy a pair of snow socks I've seen but they dont list the correct size for my tyres (255/30/19), they list a size of 245/35/19 and Another at 245/40/19. The width of my tyres is bigger by 10 at 255 but as the height is only 30 should i add that extra 10 in width to the height thus going for the 245/40/19 option? Or is a tyre height/width relationship not that simple and the 245/35/19 will suffice, confusion reigns lol Any help appreciated guys __________________ YMB M4 E93 320d Msport - sadly gone to the salvage yard.
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10-13-2011, 03:43 AM	#2
B33M3R Captain 96 Rep 831 Posts Drives: F31 335d XD M Sport Join Date: Oct 2010 Location: Cambridgeshire iTrader: (0)	I may be wrong but I thought the profile reference on a tyre ??/30/?? or ??/35/?? etc. was the profile represented as a percentage of the tyres actual width rather than a specific unit of height? So a 225/30/?? or 255/30/?? would have quite different profiles albeit with the same profile reference Don't know if that assists __________________ F31 335d M Sport XD - Mineral Grey - Coral Red - 19" 442M - HK Audio - M Sport Plus Pack - Heated Seats Check out my E90stereo install guide - http://www.e90post.com/forums/showthread.php?t=540954
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10-13-2011, 02:57 PM	#3
parapaul Colonel 118 Rep 2,216 Posts Drives: E91 330d M Sport Join Date: May 2010 Location: Stoke on Trent iTrader: (1) Garage List 2007 E91 330D MSport [0.00]	He's right. The profile is a % of the width. I'd be reluctant to gamble on deliberately buying the wrong size - can you email the manufacturer and ask them? It's not as if BMWs are rare or unusual cars with wacky tyre sizes! __________________ Just how many Yorkshire sheep can you fit inside one exhaust?
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10-13-2011, 04:34 PM	#4
chedixon Lieutenant 63 Rep 438 Posts Drives: F82 YMB Coupe Join Date: Aug 2011 Location: Nottingham iTrader: (1)	Thanks guys, there from asda direct so I'll try them first, see if they can help, was just trying to get my head around it __________________ YMB M4 E93 320d Msport - sadly gone to the salvage yard.
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10-14-2011, 05:52 AM	#5
rich1068 has left the building 90 Rep 3,359 Posts Drives: F30 330d M Sport Join Date: Oct 2010 Location: UK iTrader: (0)	Have a look here. There were some very useful links posted.
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