For optimum performance we recommend
that rubber tires be replaced when
approximately 30% of the available rubber tread
is used.
To assist you in deciding when to change the tire
we suggest you use the following formula:
OD
= Original outside diameter
of tire
ID
= Inside diameter of tire
X
= Maximum recommended wear
Y
= OD at which tire should be changed
Formula to obtain wear:
X
= [(OD - ID) ÷ 2] x .30
Y
= OD - X
Example: 18 x 6 x 12 1/8
X
= [(18 - 12 1/8) ÷ 2]
x .30 = .881
Y
= 18 - .881 = 17.12
Conclusion - Tire should be changed when the OD
is reduced to 17.12
