Belt Length Formula

[aj-allen]

Belt Length Formula

L = (2C + (1.57*(D + d))) + ((D - d)^2)/4C)

Where:
L = Belt Length Non clutched add .5 to 1 inch for most clutched applications
C = Length Center to Center shafts
D = Diameter of Large Sheave
d = Diameter of Small Sheave

Diameter of the Sheave means the outer most diameter of a new belt in the Sheave

[NO0C]

Or: http://www.calculatoredge.com/mech/vbelt%20length.htm

[KE4AVB]

I also found that when replacing a 1/2" (A section) v-belt with a 5/8 (B section) you simply add 1-1.5 inches for deck applications with two spindles. Just depends on how many V pulleys involved and their diameters. The more v-pulleys you have the longer you need to adjust the size. I have done several upgrades to B sections because of constantly breaking A sections.