wheel offset
 

I have been asked about the offset measurment on my wheels. How do I get that measerment.

1. Cut a straight stiff piece of wood so the it just spans the diameter of the wheel(be sure that it does not touch the tire), this is used to demarcate the front and rear face planes of the wheel
2. place the wood on a diameter of the front face plane of the wheel, measure to the wheel mounting face
3. do the same on the back of the wheel.
4. add the 2 measurements, then divide by 2
5. subtract the calculated value in step 4 from the measured value in step 2
6. multiply by 25.4 to convert to mm

[list=1][*]4.5" from front face plane to wheel mounting face plane[*]6" from rear face plane to wheel mounting face plane[*]4.5 + 6 =10.5" this is the total width of the wheel ** please note this in NOT the advertised width[*]10.5/2 = 5.25"[*]5.25 - 4.5 = 0.75"[*]0.75 x 25.4 = 19.05mm[*]voila! the wheel o/s is +19.05mm[/list=1]

Most wheels will have specs stamped on them, usually on the inside. Offset is usually preceded by the letters ET.

Scott