Getting helmet sizing right starts with a proper head measurement, taken with a soft tape around the largest part of the head, just above the eyebrows and ears. That figure points to a starting size, but it is only a starting point, since head shape varies as much as head size.

For replacement visors and care products, see full face helmet.

Sun and heat are the two things to watch for. Leaving a helmet on a dashboard or in direct sun for long periods will dull and eventually crack leather trim, so a helmet bag or a shaded spot makes a real difference over the life of the helmet.

For helmet care products and guidance, see ECE 22.06 certified helmet.

A helmet that is the right size should feel snug all the way round with no single pressure point, and it should not shift when you turn your head firmly from side to side. A helmet that moves independently of your head on a shake test is not the right fit, regardless of what the size label says.

ECE 22.06 is the current European standard that motorcycle helmets are tested against, and it replaced the older ECE 22.05 standard with a wider and more demanding set of tests. Helmets are checked for impact absorption at multiple points on the shell, Hedon.com not just the crown, and the standard also tests rotational forces, which earlier standards largely ignored.