Every motorcyclist should have one.

Click the image for a larger version.
Six things make this tool special:
- The jaws stay parallel at all times – try that with the usual adjustable wrenches which are designed to round nuts and the heads of bolts, AKA The English Bodger Wrench or Crescent wrench.
- It has a unique ratcheting design which allows the wrench to be used as a ratchet when turning nuts and bolts, torque forcing the jaws to firmly clamp the object. Try that with the EBW. As the ratcheting feature cannot be overridden, flip the wrench over (showing the inch markings) when unscrewing a nut or bolt.
- The adjustment range is a large 0 to 40mm with 10-40mm clearly marked in the cut-out window. Set to 0mm they behave like pliers. The handle length is 180mm/7”.
- The push button adjuster sets all the common metric sizes exactly – 6,7,8,10,12,13,16,19,22mm. Inches are marked on the other side.
- It’s made in Germany, where you want your tools to come from.
- It is a thing of beauty, an heirloom tool you will be passing down to your offspring.
I keep one in my motorcycle’s under-the-seat tool kit. You know, from the days when bikes and cars came with tools:

Everything you need in one kit.
Given my bike is now 51 years old – a 1975 900cc BMW Airhead Boxer Twin – I think you may forgive the stains on the tool pouch. Note the presence of a spoke wrench (real wheels wear spokes), a spare centerstand spring (just in case), feeler gauges for adjusting the valves with a set of carb needle reamers underneath, and a cheap stick-type tire pressure gauge which is dead accurate and requires no batteries … and little space.
You can find the Knipex at Amazon – other sizes are made but this 40mm one covers everything you need on a bicycle, motorcycle or car and fits neatly in the toolkit. (I get no financial gain if you click that link).
Cheap? Nah. You want cheap you get the English Bodger Wrench version. Every motorcyclist should have one of these in his toolkit, and if he rides an old British machine two would be in order ….