Cones are those conical bits (obvious or what – Ed) that hold the bearings in your wheel stable and make the wheel run perfectly. I’m sure that in the past I have battled to adjust the cones on a bicycle wheel with a variety of normal open spanners… or maybe even an adjustable spanner, or even worse, some pliers. But it’s another one of those jobs that does require the right tool, if only to ensure that the bearings don’t work loose within a few miles of the first ride.
Another of Murphy’s Laws of bikes says that the cones on your particular wheel won’t fit the one cone spanner that you have in the toolbag – so you’ll need several.
Over recent years I have ended up with two Pro Cone Wrench Set, the 13mm/14mm and 15mm/16mm sets, and I reckon that I’ve used every one.
I did find a Cyclo Cone Spanner at Chain Reaction Cycles, and that combines four cone sizes into one spanner – a brilliantly simple idea.
One word of warning, cone spanners tend to be fairly soft (cones shouldn’t be done up extremely tightly and I guess they can get away with being lighter material). So don’t over-tighten the cones, or you risk damaging the spanner itself.