For a BMX bike, if you want to add pegs to your bike, how do check what...

If its a skinny axle then you need 3/8" if you have fat axles then you need 14mm.

Get a ruler and measure the diameter of the axle.If it's 14mm get 14mm pegs, if it's 10mm get 10mm or 3/8" pegs. The back axle might be bigger than the front axle.

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