Motorcycle helmet straps: why MotoGP requires the Double D

MotoGP doesn't ban two helmet fasteners out of three on a whim: since 2019, FIM rules have made the Double D buckle mandatory on every helmet used in MotoGP, Moto2, Moto3 and WorldSBK. The reason comes down to two words: precision and reliability. Two metal rings, not a single plastic part, and tension set to the millimeter every time you do it up. The other two systems, ratchet and magnetic, are perfectly good on the road, but neither gets anywhere near that level of adjustment.

What are the three motorcycle helmet strap systems?

Motorcycle helmets use three chin strap systems: the micrometric ratchet buckle, the Fidlock-style magnetic buckle and the two-ring Double D. Each one was designed for a specific job, and each one has a weakness you can put your finger on. The table below sums up what separates them.

None of these systems is bad in itself: all three are fitted to approved helmets. The real question is what each one puts first, everyday speed or precision of hold. That's exactly the call the racing world has made.

The ratchet buckle: why is it on almost every road helmet?

Because it's simple, quick and easy to use with gloves on: a toothed tab clips into a ratchet mechanism, and the helmet is shut in a second. In the video, Thomas compares it to a zip tie: you push, it clicks, it's locked. For daily riding, city trips and the commute, nothing beats it for convenience.

Its weak point sits in the very way it works: the ratchet moves one notch at a time. Between two notches there is nothing. So you're almost always somewhere in between, one notch too tight or one notch too loose. It's no disaster for riding, but it's never exactly the tension you'd want. Most riders get used to it without a second thought, and that's precisely why it's everywhere.

The magnetic buckle: how good is a cellist's invention?

The magnetic buckle is the easiest of the three to handle: two magnetized halves that pull towards each other, line themselves up and lock with no effort and no precision needed from you. The backstory is worth the detour, and Thomas tells it in the video: the system was invented by a German cellist who'd had enough of the catch on his instrument case. The idea then made its way onto helmet chin straps.

You'll mostly find it on adventure and off-road helmets, where the helmet comes off and goes back on several times a ride, sometimes with thick gloves and mud on your fingers. On that ground, how easy it is to use makes the difference. The trade-off: the tension depends on how you set the strap yourself. The magnet locks, but it doesn't adjust anything for you.

Why is the Double D the racers' favorite?

Because it's the only one that gives you exact tension, with no notches and no preset positions: you thread the strap through the two metal rings, pull it as tight as you want, fold it back, done. No mechanism, no plastic, just webbing and metal. There is literally nothing to break.

"It's the most annoying one to fasten, but you only have to do it once. After that it's just great, and seriously comfortable," says Thomas, GeoRide founder.

That's the Double D paradox: it asks for a bit of practice, and that's exactly why it puts people off. But once the movement is second nature, it does something no other system does.

"The adjustment is seriously precise: you pick, down to the millimeter, exactly how tight it goes," says Thomas, GeoRide founder.

That millimeter-perfect tension, identical every time you fasten it, is exactly what you want from a chin strap: a helmet that stays put, with no pressure point under your jaw.

What exactly have the FIM rules said since 2019?

Since 2019, helmets used in MotoGP, Moto2, Moto3 and WorldSBK have to be fitted with a Double D buckle. Thomas quotes the FIM rule word for word in the video: "the double D ring system must be present". In other words, ratchet and magnetic buckles are effectively shut out of top-level racing.

The logic is crystal clear. In racing, a helmet has to stay perfectly in place whatever the forces involved, and the rider has to get exactly the same tension back at every session. The Double D ticks both boxes: tension chosen to the millimeter, and a build with no plastic parts, so its reliability hangs on no mechanism at all. When the bodies that govern the fastest riders on the planet make one system compulsory, that's not a footnote in a rulebook, it's a solid clue about what works best.

And on the road, what does this change for you?

The right move isn't to change helmet, it's to take care of the adjustment on the system you already own. A properly set chin strap means a helmet that stays exactly where it belongs and does its job 100% the day you need it. Ratchet, magnetic or Double D: take two minutes, stopped, to find the right tension, the one that holds without pinching.

That small habit is part of a wider routine, the one we go through in our checklist of safety points to run through before you ride. And if the helmet protects you during the fall, what comes next matters just as much: getting help fast. That's the whole point of fall detection on a motorcycle, which takes over when you can no longer raise the alarm yourself.

Your helmet protects you during the fall, GeoRide takes over right afterThe device picks up the impact and raises the alarm in under 2 minutes, even with a smashed phone: automatic emergency call in France, your loved ones alerted wherever you ride.

Protect your motorcycle

Where GeoRide fits in

A properly fastened chin strap protects your head during the fall; GeoRide handles what happens in the minutes that follow. The GeoRide GPS tracker detects a fall while you're riding and, if you don't respond, raises the alarm automatically in under 2 minutes, in the right place: the tunnel operator's team if you're in a tunnel, the motorway control center on a motorway, the fire brigade or the ambulance service anywhere else. Emergency services are dispatched in mainland France; everywhere else your loved ones are alerted automatically. And because the device works independently of your phone, the alert still goes out even if yours is dead or smashed in the slide.

Off-road fans, the very riders who often run a magnetic buckle, will appreciate off-road mode: the small, frequent tumbles that come with the terrain don't call anyone out, only a genuine emergency does, and location sharing with your loved ones stays active. This GPS tracker naturally rounds out good gear, the same way smart helmets do, and GeoRide teams up perfectly with them or the smart accessories that make a rider's life better.

The device installs in 5 minutes on any motorcycle, and where rental is available (France, Belgium, Italy and Switzerland) it starts at €9.99/month with no commitment, fall detection and automatic emergency call included. A helmet properly strapped on your head, a GPS tracker on the bike: the two links back each other up, one during, one after.

FAQ

Which helmet strap is the safest?

The Double D buckle is the benchmark: it's the system the FIM has required since 2019 in MotoGP, Moto2, Moto3 and WorldSBK, thanks to its millimeter-perfect adjustment and its build with no plastic parts. Ratchet and magnetic buckles are fitted to approved helmets too and stay reliable, as long as they're set correctly.

Can you fasten a Double D with gloves on?

You can, but it's fiddly: threading the strap through the two rings takes a bit of dexterity. Most riders fasten the helmet before pulling their gloves on, and that's the right way round. As Thomas puts it, you only do it once per ride: the small effort of closing it is forgotten within the first few meters.

Is a magnetic buckle reliable on the road?

Yes, Fidlock-style magnetic buckles are fitted to approved helmets and lock securely. Their real quirk is elsewhere: the magnet closes, but it doesn't adjust. The tension depends on how you set the strap yourself, so take the time to get it right once and for all.

How do you know your chin strap is properly adjusted?

With the helmet fastened, the strap should stay in contact with your skin without stopping you from opening your mouth, and the helmet shouldn't tip forward when you push it from the back. If it moves or rotates, take it up a notch (or a few millimeters on a Double D) until it stays perfectly put.