Helmet Fit Guidelines...
There is much to be said about going into a Motorcycle shop and physically trying on the helmet you are considering. Even if you plan on buying online, knowing what size you need will save much time and aggravation. Cheaper is not cheaper if you must exchange by mail repeatedly, or end up with a helmet that doesn't fit well, or worse, is painful to wear after 30 minutes.
I did not devise this fit guide, but I took what I was taught and put it to paper to share. I believe it is based on the Arai fit method, but is applicable for all makes. This is what I was taught while working in a MC dealer. I have tweaked it in an effort to make it understandable in print. I have also added details that I have learned through experience in an effort to make it as helpful as possible.
Do NOT under any circumstances purchase for use, a USED helmet. Not "still in the box," not "only worn once," not "free with the bike." Hidden damage that even the previous owner is unaware of can kill you if you go down wearing that bargain helmet. Don't take the risk.
1. Do NOT look at prices first. Fit is most important. If Arai (generally the most expensive) fits, then that will provide the BEST protection, if an HJC (generally a less expensive make) fits, then THAT will provide the best protection. For this ‘fit test’ do not buckle the chin strap. If you wear glasses, or sunglasses while riding, don’t forget to have them with you for the fit test. Note: At a helmet seminar offered by Arai, those in attendance learned that about 60% were wearing helmets too BIG for best protection. Recently, I learned that I've evidently been wearing a helmet TWO sizes too big, while shopping to replace my "crashed in" Arai helmet. For fit-trying helmets, a Buff or Sliks helmet liner, or other snug fitting "do-rag" is VERY helpful, especially if you've got multiple ear piercings or thick hair, etc.
2. Choose a size that looks close (you gotta start somewhere). Pull the helmet on over your head by holding the straps. It should go on with a bit of work, but NOT so tough it feels like your ears are being scraped off your skull. If the helmet goes on with little or no effort, try the next size DOWN. Tilting your chin slightly down should ease neck strain in doing this.
3. Flip up the face shield. (If trying a helmet with flip up chin bar, ONLY flip up the face shield.) Now, push the helmet around on your head. Have someone watch your face, or look in a mirror, while you do this. Your scalp and eyebrows should move around with the helmet padding. If it doesn’t, try the next size down OR a different make of helmet and repeat from #2. If your scalp does move, close your eyes and think about how the padding feels around the crown of your head. You should feel snug EVEN pressure all around, like a good firm handshake - no ‘hot points’ at forehead or ears. Some helmets give a sort of "chipmunk cheek" feeling. Remember, the padding will compress with wear, so snugness is good in a new helmet, rather than a ‘just right’ fit, or it will become too loose with wear. Some helmet manufacturers offer thinner cheek padding if this is your main concern. (If you feel a hot point at forehead, you probably have an ‘oval profile’ head and should try one of the Arai models.)
4. Fasten the chin strap snugly (so you can just get one finger underneath): Tilt your chin down to your chest and take one hand and push UP on the bottom of the back of the helmet. You should NOT be able to push the helmet off, or part way off. If you can, then try another make or size helmet.
5. Once you’ve gotten to this point, wear the helmet around the shop for at LEAST 10 to 15 minutes. This is where using a full service shop is worth it. They should encourage you to wear the helmet for some time before buying. You don’t want to find out after you plunk down $$, that the helmet you thought fit you is agony to wear for more than 30 minutes. If you are indecisive about two different helmets, make sure you WEAR the 'most likely candidate' last, before purchase. If this is it. Buy it. Get the box and packaging for the helmet, if at all possible. THEN, take the new helmet home and wear it while watching TV or 'surfing the net' for an hour or two... it can be tough to really get used to the fit, when somebody is staring at you (don't think about pink elephants right now), so wearing it while doing something else is probably the best way to make sure the fit is right. If you have any fit "issues" after this last at home test, RETURN the helmet. A reputable shop should have no issues with taking an ill fitting helmet back. ASK ABOUT THE RETURN POLICY BEFORE YOU PURCHASE.
A) Motorcycle Helmets should be retired/replaced EVERY five years, or at a maximum of seven years from date of manufacture (month/year usually imprinted on chinstrap or on label inside). When buying a 'clearance' helmet, the low price is often because the helmet is already 2-3 years old. No way to tell how well or poorly a helmet has been stored.
B) No matter how well taken care of, a helmet that has been dropped should be replaced. A helmet that has been in a crash MUST be replaced for your safety (your insurer may cover replacement of your helmet and/or other safety gear).
C) Always make sure you have a clear face shield (visor) available for your helmet. Carry one in your tank bag. If you find yourself out later than planned, or if the weather should change, it is dangerous to ride in low-light conditions with even the lightest tint visor. You won't realize what you are not seeing until it is too late.
D) NEVERNEVERNEVER use any paper product (paper towels, tissues etc.) to clean your face shield. The tiny wood fibers will create microscratches in your visor over time. Use only cleaners made for plastics to clean your face shield. Products such as Rain-X and Windex contain amonia and may cause the plastic to discolor and become brittle.
Happy riding and stay safe!! LL
FOR those who are on the fence about full face/half helmet, here is an illustration created from a study done in europe of impact point percentages for a full face helmet:
Note that the FOREHEAD and JAW are the two areas in double digits percentage wise.