Size of wheels

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Hi all,
Just a quick one�I have just bought a set of 17" wheels that have 225/45/17 tyres. I am fairly certain but can someone confirm that they will be ok regarding the speedo reading and gearing-I currently have standard 225-60-15 rims--thanks

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Phillip Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member I Joined: 16-August-2004 Location: Nantwich, Cheshire Status: Offline Points: 100	Topic: Size of wheels Posted: 28-September-2004 at 11:25
	Hi all, Just a quick one�I have just bought a set of 17" wheels that have 225/45/17 tyres. I am fairly certain but can someone confirm that they will be ok regarding the speedo reading and gearing-I currently have standard 225-60-15 rims--thanks
	Philip

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e34m5 Members Profile Send Private Message Find Members Posts Add to Buddy List Really Senior Member II Joined: 26-June-2003 Location: Near Rugby, Warwickshire Status: Offline Points: 1344	Posted: 28-September-2004 at 11:32
	The overall roling radius of the new wheels is 2.6% smaller than the originals which is not ideal (most people recommend a maximum difference of +-2.5%) but they should be fine Your speedo will be even more over optimistic than normal Miles
	1991 525i Sport Manual

Jimbo540i Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: 05-May-2004 Location: United Kingdom Status: Offline Points: 80	Posted: 29-September-2004 at 05:12
	Hi Phillip check this previous post of mine - tells you how work this sort of thing out... http://www.bmwcarclubforum.co.uk/forum_posts.asp?TID=10559&a mp;PN=2 Cheers Jim
	Jimbo 540i Auto

harvard468 Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: 05-August-2004 Location: United Kingdom Status: Offline Points: 95	Posted: 29-September-2004 at 05:26
	Hi Philip, Your overall wheel with tyre will be 0.65 inches (17mm) smaller - as E34M5 says - 2.6% smaller. My E39 M5 has 225/40 on the front (orevious owner!) instead of the recommended 245/40 which are 16mm smaller overall - 2.45%. The car drives fine. I agree you should be fine although your speedo will as mentioned above be 2.6% more optimistic than at present - maybe will help avoid speeding tickets. Maybe I should put 12 inch rims on my car!! Regards STEPHEN B
	Stephen B 1990 Z1 1994 E34 540i Touring 1999 E38 740i (Had to go) 2001 E39 M5