Why You Need to Replace a Mountain Bike Helmet After a Crash… Unless It Has Nano Core from Kali Protectives


Most of us have heard that mountain bike helmets need to be replaced after a serious crash, but the thing is, few riders actually follow through. Often times a helmet will come out of a crash looking ok: the shell might have some scratches, but there are rarely visible cracks inside or outside the helmet. Heck, the helmet generally even feels the same, with nothing loose or disjointed.

However, looking at this cut-away of a mountain bike helmet that’s been impacted once during testing makes it clear that the crashed helmet is damaged:


As you can tell from the photo, the EPS foam has been compressed due to the impact, even though the shell and the inside of the helmet appear unchanged. This means the next time the helmet takes a hit in this area, all the energy of the impact will be transferred to the rider’s head instead of being dissipated through EPS compression. Put another way, EPS doesn’t bounce back to its original shape after being deformed.

Now, here is a cut-away from the new Kali MacDuff helmet with a Nano Core liner:


I was told this helmet had been impacted in the same way as the EPS helmet shown above, and as you can see, the foam has not been compressed. Even more impressive: this helmet has been impacted in the same spot multiple times.

Kali is using Nano Core in three of their latest helmets, though the MacDuff is the only one that is rated multi-impact, meaning it’s ok to keep using the helmet after a crash. This skate-style helmet won’t be mountain bikers’ first choice, but for BMX riders and dirt jumpers, this lid might just be a game changer.

Shiva 2.0
Shiva 2.0

On the mountain bike side, Kali has two updated helmets: the Shiva 2.0 and the Interceptor. The Shiva 2.0 is a full face helmet that utilizes both Nano Core and traditional EPS foam with a structural outer carbon shell. Like the Shiva 2.0, the Interceptor uses both Nano Core and EPS but in a vented, enduro-style shell. While these helmets are not rated multi-impact, Kali does offer “Lifetime Crash Replacement,” which is great for consumers, but seemingly a little insane for the company to offer.

The green and yellow bits are Armourgel. Also note the pulley system for the Boa ratchet system.

Beyond the foam core of these two helmets, Kali also incorporates their own MIPS-style concussion reduction technology called LDL (not to be confused with the cholesterol measurement). LDL is a series of low profile, round Armourgel nubs that allow the helmet to rotate somewhat independently of the rider’s head in the event of a crash, reducing the chance of a concussion. To be clear, reducing the chance of a concussion is not the same as preventing a concussion.

Night riding, anyone?
Night riding, anyone?

The new Interceptor enduro helmet includes a sleek-looking rail system that allows riders to add a light or helmet camera mount directly to the helmet. When the mount isn’t in use, a cover can be popped into the rails to keep everything neat and aero.

Stay tuned for full pricing and availability on these new helmets from Kali Protectives.

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