Cycle information - Cranks with 3 chainring bolts

Use these bolt spacings to identify your crank's pcd and smallest chainring.
For other 3 bolt cranks: pcd = 1.1547 × bolt spacing.

3 bolt chart

There is wide variation between 3 arm products with nominal pcds of 116.0 and 116.5mm. You may have to file a chainring's bolt holes to make it fit your crank.
The minimum size of an Oval depends on its ovality - it is greater for ovalities more than 20% and smaller when less than 20%. The minimum number of teeth for 3-bolt cranks may be estimated as follows:

minimum Oval  =       minimum round     
                 1 - ( 0.004 × ovality )

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