Measuring Rim Width
Thread Starter
Burning Brakes
Joined: Mar 2007
Posts: 984
Likes: 1
From: SAN FRANCISCO CA
Measuring Rim Width
hey guys - not a vette specific question, but, i'm getting some new rims for my DD and i'm getting them off a friend. he doesn't know what the rim width is and i'm wondering, do i just measure it from edge to edge or is there a specific way to do it? i need to order meat for the bone so i've gotta know how much meat i can fit, know what i mean!!!??
Safety Car
Joined: Sep 2003
Posts: 4,206
Likes: 8
From: Belmar NJ
Measuring rim width and backspace can get tricky as there are a couple ways to look at it and the differences can be as much as 5/8".
The easy way for width is outside to outside but this may or may not match the mfg. measurement. Getting closer to correct would be inside lip to lip. Most mfg. measure this way. Backspace same way, either outside lip or inside (more accurate in this case usually is outside). If the rim beads the tire other than on the lip itself the measurements can change again. Buying wheels long distance has some pitfalls. If at all possible, get pix of the wheel with tape measure and work whichever numbers you need to see if they will fit. /:\
The easy way for width is outside to outside but this may or may not match the mfg. measurement. Getting closer to correct would be inside lip to lip. Most mfg. measure this way. Backspace same way, either outside lip or inside (more accurate in this case usually is outside). If the rim beads the tire other than on the lip itself the measurements can change again. Buying wheels long distance has some pitfalls. If at all possible, get pix of the wheel with tape measure and work whichever numbers you need to see if they will fit. /:\
Race Director
Joined: Jan 2007
Posts: 14,919
Likes: 3,333
From: NYC NY
Measuring rim width and backspace can get tricky as there are a couple ways to look at it and the differences can be as much as 5/8".
The easy way for width is outside to outside but this may or may not match the mfg. measurement. Getting closer to correct would be inside lip to lip. Most mfg. measure this way. Backspace same way, either outside lip or inside (more accurate in this case usually is outside). If the rim beads the tire other than on the lip itself the measurements can change again. Buying wheels long distance has some pitfalls. If at all possible, get pix of the wheel with tape measure and work whichever numbers you need to see if they will fit. /:\
The easy way for width is outside to outside but this may or may not match the mfg. measurement. Getting closer to correct would be inside lip to lip. Most mfg. measure this way. Backspace same way, either outside lip or inside (more accurate in this case usually is outside). If the rim beads the tire other than on the lip itself the measurements can change again. Buying wheels long distance has some pitfalls. If at all possible, get pix of the wheel with tape measure and work whichever numbers you need to see if they will fit. /:\
The only thing I'll add is have your friend take a good look at the wheels. A lot of them are marked what size they are in a inconspicuous (spelling?) area on the backside of the wheel.
Race Director
Joined: Jul 2005
Posts: 13,685
Likes: 61
The accepted wheel industry measurement is between the inside shoulders. Most alloy (mag) wheels that measure seven inches between outside rim edges are actually measured and catalogued as six inches by the manufacturers, distributors and retailers.
