Mountain Biking - Full face helmet sizing

Im looking to get a full face helmet soon but am not sure which size to get. Exactly which part of my face would I measure for the correct size helmet. I think i would need to measure the largest part of my head (right over my eyebrows) but am not sure.

I'm not totally sure. But if you go 661. Most of there helmets run VERY small. I have an XL and its a tight fit.

well helmets dont seen to vary that much in size, so i suggest just try on different helmets till you get a good fit.

has anyone tried the Casco viper MX? it feels quite light for a full face helmet

ok because i was going to order offline so i cant really try on any helmets. the only shop which carries full face helmets around here is 35 miles away which is quite the drive.

getting back to your question and just what I have found by trying on helmets and looking at the sizes is that the size in the helmet appears to correspond roughly to a horizontal cross section of the skull measured at the widest part (round the forehead). But some helmets have slightly different shapes (more oval/less oval) is it is better to try them on if you can

Im looking to get a full face helmet soon but am not sure which size to get. Exactly which part of my face would I measure for the correct size helmet. I think i would need to measure the largest part of my head (right over my eyebrows) but am not sure.
get a tape measure and measure the circumfrence of your head just above your ears.

Wow...personally with my experience with full face I wouldn't buy one. They all fit completely different. Bell is round, Louis Garneau is slightly oval...661 is just messed and fits very few people. Size is almost irrelevant with full faces. And there is no standard (as with everything in biking) way to measure.

Wow...personally with my experience with full face I wouldn't buy one. They all fit completely different. Bell is round, Louis Garneau is slightly oval...661 is just messed and fits very few people. Size is almost irrelevant with full faces. And there is no standard (as with everything in biking) way to measure.


I'm one of those very few that 661's fit. Its a tight fit. But you forget about it when your bombing down the hill! Going on my first full day of DH with it tommorow.

for full face you don't measure you just go to the bike shop take a helmet and put it on and it should feel tigh around your face and then you push the part where it protecting your jaw and if it pushes towards your face then you need a smaller size and the pads will wear out to dont'; worry if it kills your face, or just ask the bike shop people to help you out.

Later (selling z150fr $650)

well if you plan to order it, and wont be able to actually try it on then youll just have to take your best guess and if it dosnt fit, send it back