Stupid question ..

Chitown-Irish · 10-06-2008, 12:29 PM

How do you determine the diameter of a wheel?

Is it measured from outside edge to outside edge?

Also can 18" tires be mounted on 19" wheels?

Please be kind and don't flame me.

mithiral67 · 10-06-2008, 01:06 PM

I think the best way is to take the diameter measurement from the inside groove that the tire sits on. It’s easiest to measure the inner diameter of the tire after it’s removed from the wheel.

I am no 100% on the 18in on 19 inch, but I am pretty sure thats impossible. Low profile tires are hard enough to mount as is, trying to stretch an 18 on a 19 probably wont work.

Gary@TireRack · 10-07-2008, 12:15 PM

Or just look at the back of the wheel as it should be stamped there.

10-06-2008, 12:29 PM	#1
Chitown-Irish Second Lieutenant 15 Rep 292 Posts Drives: 11 X3 xDrive35i Join Date: Mar 2008 Location: Orland Park, IL iTrader: (0)	Stupid question .. How do you determine the diameter of a wheel? Is it measured from outside edge to outside edge? Also can 18" tires be mounted on 19" wheels? Please be kind and don't flame me. __________________ 2011 X3 xDrive35i F25 (CPO) Space Grey/Black Leather, Packages: Premium, Cold Weather, BMW Apps, Sirius and Technology. BMW CCA Member (WindyCity Chapter). Former cars: 06 750i E65 (CPO) 07 E90 335i (bought used but had problematic iDrive so sold it to get 7-series)
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10-06-2008, 01:06 PM	#2
mithiral67 That guy 120 Rep 5,740 Posts Drives: 2015 Cayman GTS Join Date: Jun 2008 Location: Chicago Burbs iTrader: (4) Garage List 2015 Porsche Cayman ... [0.00]	I think the best way is to take the diameter measurement from the inside groove that the tire sits on. It’s easiest to measure the inner diameter of the tire after it’s removed from the wheel. I am no 100% on the 18in on 19 inch, but I am pretty sure thats impossible. Low profile tires are hard enough to mount as is, trying to stretch an 18 on a 19 probably wont work.
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10-07-2008, 12:15 PM	#3
Gary@TireRack Moderator 372 Rep 4,742 Posts Drives: Formerly 1995 M3 Join Date: Oct 2006 Location: South Bend, IN, Tire Rack HQ iTrader: (2)	Or just look at the back of the wheel as it should be stamped there. __________________ Gary. Tire and Wheel Forum Moderator. Tire Rack Sales Rep Gary@Tirerack.com http://www.tirerack.com/a.jsp?a=AH8&url=index.jsp Please refer to 'Gary/E90 Post' as your previous contact when you order online to help support this forum.
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