WHAT PEDAL AXLE DIAMETER DOES MY BIKE HAVE?

April 15, 2005

    I have a dumb newbie question.
    I recently bought a 2004 Raleigh Sport road bike. This is my first "good" bike (yes, I know the term "good" is relative).
    Anyway, every bike I’ve ever owned has had plain platform pedals. I am conditioning for a 150-mile ride, and I know these just won’t work. The bike came with 15mm (I believe) pedals with clips, which I hate. I am considering buying a set of pedals that are platform/clipless hybrids (platform on one side for casual rides, clipless on the other for the long rides).
    Here’s my concern: The pedals I am looking at are 9/16". Like I said, I believe the Raleigh bike came with 15 mm standard. Is this an issue? Thanks.

Matt G.

Matt:
    Pedal axles (also called "spindles") generally come in either 9/16 or 1/2 inch diameters.
    Your misapprehension comes from hearing about the size of the wrench used to unscrew and screw in the pedal. For most 9/16 inch pedals you can use a 15 mm wrench to grab the appropriate part of the pedal, called the "wrench flats" or simply "flats." (Looks to me like a hex nut, but what the heck.)
    So which pedal diameter does your Raleigh have—9/16 or 1/2? I’d bet on 9/16. Why? You’ll often find 1/2 inch pedals on kids’ bikes, and not commonly on decent road bikes like yours . . . unless your bike has a French crankset, in which case forget all of the above. (Luckily, highly unlikely.)
    By the way: When you start learning on those new clipless pedals, take your first bunch of rides in quiet areas where you won’t have to stop suddenly—until you learn to clip out real quick. You can often tell newbie clipless bikers by their cuts and bruises.

Mr Bike

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