You have a few solid options for carrying a motorcycle helmet: clip it to a backpack, use a dedicated helmet bag, lock it to your bike, or store it in a top case. The best method depends on whether you’re walking around off the bike, riding with a spare helmet, or leaving it parked.
Carrying a Helmet While Walking
The simplest approach is hooking the helmet’s chin strap over your arm or looping it through a bag strap, but this gets uncomfortable fast. A full-face helmet weighs 3 to 4 pounds, and dangling from one hand or forearm, it becomes a nuisance within minutes. If you’re heading into a store, restaurant, or workplace, you want something better.
A helmet bag is the most compact solution. These are lightweight drawstring or zippered bags, often with a fleece lining to protect the visor and shell finish. They fold flat when not in use and slip into a backpack or messenger bag. The main advantage is scratch protection: tossing an unbagged helmet into a locker or onto a desk invites scuffs on the visor and shell.
Dedicated motorcycle backpacks take this a step further. Many come with an external helmet holder, either a mesh net on the outside or a bungee system that cradles the helmet against the back of the pack. Brands like KEMIMOTO and ILM make packs in the 20 to 35 liter range with a hidden net or external carry system specifically for this purpose. Hardshell motorcycle backpacks add waterproofing and structure, so the helmet doesn’t bounce around while you walk. Some of these double as commuter bags with laptop compartments and reflective panels, which makes them practical for daily use beyond riding.
If you don’t want a specialized pack, a simple carabiner clipped to any backpack strap works. Thread it through the helmet’s D-ring or chin strap buckle and let the helmet hang at your side. It’s not elegant, but it frees both hands.
Locking It to Your Bike
Leaving your helmet on the bike is often the most convenient choice, especially if you’ll be gone for a while. The challenge is theft prevention.
Many motorcycles have a built-in helmet lock, usually a small hook under the seat or near the rear frame. You loop the helmet’s D-ring over the hook and turn your ignition key to lock it in place. Check your owner’s manual if you haven’t found yours yet, as the location varies by manufacturer and isn’t always obvious.
If your bike doesn’t have a built-in lock, or if the built-in one positions the helmet where it bangs against the paint, aftermarket cable locks are a popular fix. A simple coated steel cable threads through the chin strap’s D-ring and wraps around a frame tube, handlebar, or passenger peg. Combination cable locks eliminate the need for yet another key. These aren’t theft-proof against bolt cutters, but they stop the casual grab-and-go that accounts for most helmet theft.
One caution with any method that leaves the helmet hanging outside: rain, sun, and curious hands are all risks. UV exposure degrades the shell over time, and a surprise downpour soaks the interior padding. If you’re parked for hours in direct sun or unpredictable weather, bringing the helmet inside is the safer call.
Storing It on the Bike in a Top Case
A top case (also called a top box) mounted to your rear rack is the gold standard for on-bike helmet storage. It keeps the helmet locked, protected from weather, and completely out of sight. The key number to remember: you need roughly 29 to 32 liters of capacity to fit a single full-face helmet. A 39-liter case fits a helmet plus a few extras like a water bottle or a light jacket, though fitting all three at once can require some creative packing.
Side cases (panniers) on adventure or touring bikes can also work, but sizing varies more. If carrying a helmet is a primary reason you’re shopping for luggage, measure your helmet’s widest point and compare it to the case’s interior dimensions before buying. Modular and full-face helmets are bulkier than half-helmets, so don’t assume a case that says “fits a helmet” means your helmet specifically.
Carrying a Spare Helmet While Riding
If you’re picking up a passenger and need to bring a second helmet on the bike, you have several options. The most common is strapping it to the pillion seat using a cargo net or bungee cords. Cargo nets stretch over the seat and hold the helmet firmly against the cushion. Many riders keep a small cargo net folded under the seat for exactly this purpose.
If your bike has a pillion grab strap or sissy bar, you can thread the spare helmet’s chin strap through the grab handle and twist the strap several times so the helmet sits snug and can’t swing outward. The goal is preventing the helmet from shifting to one side, where it could contact the rear tire. Wrapping the strap three or four times before securing it keeps things tight. For bikes with a sissy bar, drop the helmet over the top of the bar and tie the chin strap around the lower crossbar.
A large tank bag is another option. Some tank bags are sized to swallow a full-face helmet entirely, keeping it padded and secure on the tank. This shifts weight forward rather than rearward, which some riders prefer for handling balance.
Protecting the Helmet While You Carry It
However you carry your helmet, the interior liner deserves some thought. The foam layer inside a helmet (the part that actually absorbs crash energy) is made of expanded polystyrene, the same material as disposable coolers. It works by crushing on impact, and it can only do this effectively once. If you drop a helmet hard enough to compress that inner foam, it should be replaced, even if the outer shell looks fine. This applies at any drop height if the force reaches the liner.
In practice, a helmet slipping off a seat onto a garage floor with no head inside it is unlikely to generate enough force to damage the liner, since the liner is designed to absorb the energy of a head’s mass during impact. But repeated drops add up, and a helmet that tumbles off the back of a moving motorcycle onto pavement is a different story. Carrying methods that hold the helmet securely, rather than letting it dangle loosely, reduce this risk.
For the exterior, a fleece-lined bag or even a microfiber cloth draped over the visor prevents the kind of fine scratches that accumulate from setting the helmet on rough surfaces. Visors are expensive to replace, and scratches create glare at night that genuinely affects visibility.