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One of the more enjoyable projects I've worked on this year at CNET has been testing various forms of rideable tech. That includes e-bikes, electric scooters, powered skateboards and hybrid devices like the Onewheel.

I've zipped through the streets of Manhattan, covering ground much faster than I could on foot or on the subway, always riding carefully but never being overly concerned about accidents. Smashups between cars and bikes do happen. But as an experienced rider and New York native, I thought the odds were on my side. I may have been a little overly optimistic about that.

Here's what happened to me while riding the Juiced Bikes CampScrambler last week. I'm fine, and so is the e-bike. But if not for my Bontrager Specter WaveCel helmet, a high-tech model just released in April, it might have been a different story.

Sarah Tew/CNET

It was Friday, Aug. 2, and I was riding to work as a test for our ongoing electric rideable roundup. It was just around 10 a.m., and I was making good time toward the office. Everything seemed fine, or so I thought.

I was heading south on St. Nicholas Avenue, approaching 124th Street. That's where the avenue hedges slightly left along with most of the traffic. Keep going straight, however, and the road turns into the lesser-used Manhattan Avenue.

There's a bicycle lane along St. Nicholas, but it's a typical old-school unprotected one, just a painted line alongside the traffic. The bike lane is on the right side of the street, and in order to proceed south on St. Nicholas, one has to cross over in front of the road that becomes Manhattan Avenue. Usually that's not a problem, as most people curve onto St. Nicholas, right alongside the bikes (and e-bikes).

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Except on this morning, it was a problem. While going with the flow of traffic and taking that curve, I noticed an SUV closing in from behind. Not only was this driver continuing straight onto Manhattan Avenue, he didn't see that I was turning to follow St. Nicholas. Unhelpfully, the traffic lights at this intersection can be confusing.

I veered back to the right to avoid the driver, but I wasn't fast enough. The SUV just barely clipped my handlebars and I went flying, landing on a combination of head, shoulder and arm. Fortunately, neither of us was going fast and he stopped right after contact. I stopped right after contact with the ground. The driver explained that he didn't see me. I was just grateful to be in one piece.

An ambulance arrived on the scene. I thought I felt fine, except for a slight ringing in my head. They took my blood pressure and gave me a quick look-over, but I was well enough to just drop by the hospital on my own later on.

It wasn't until shortly after that I stopped to look at the condition of my helmet. With only a small abrasion on my scalp and some ringing, I hadn't given it too much thought. But upon an even cursory inspection, I saw the rear left side of the helmet had been damaged where it hit the street.

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And it wasn't just a simple ding. The Specter WaveCel helmet by Bontrager is lined with a thick layer of ribbed material, designed to absorb and distribute impact energy. The company describes it as a "collapsible cellular structure that lines the inside of your helmet." Even though the helmet is light and airy, Bontrager cites studies saying it can be 48 times more effective than a standard foam helmet in some kinds of crashes.

The outer plastic shell was a bit scuffed and slightly ripped, but didn't look too bad. Under that layer, however, the cellular ribs were crushed and malformed, indicating that they had absorbed a huge impact. If I hadn't been wearing it, I don't want to imagine what could have happened.

Joseph Kaminski

At my local bike shop, they confirmed what I already knew -- that once a helmet has sustained a serious impact it should be permanently retired. Temporarily sidelined, but expected to make a full recovery, were my two iPhones.

I plan on continuing to enjoy e-bikes, electric scooters and other rideables, but I'm also going to always remember to keep my helmet game tight.