Smith Jetstream TT MIPS Helmet Review

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The Smith Jetstream TT MIPS helmet is geared toward any cyclist wanting to find a more aero position either in a road time trial or triathlon. I dabble in both arenas, and usually do most of my riding on the road bike. No Aero helmet needed for that. With that said, I will focus on this helmet from the Triathlete standpoint, as I am training for an Ironman this year.

Triathletes are a curious bunch in the cycling community. It’s all about aero, lightweight, and any little advantage one can muster from the bike, gear, attire, and positioning. This tri world has been innovative in many ways which has trickled down to the roadies (if they want to admit or not). The Smith Jetstream TT helmet has certainly come a long way from those 1980’s Styrofoam shells. Watch the Tour De France’s time trials, and you will see quite the array of helmets. I see a likeness to a Darth Vader Helmet. Team Visma-Lease-a-bike and Uno-X Mobility come to mind as having very unique looking aero lids.

Now who’s looking the fool. Just kidding. Those big Dollar Pro tour teams have testing budgets that eek out every little kilogram, watt, and time savings possible. And over time, that technology does make it’s way down to the average guy out there on a bike. That would certainly be me, as well as thousands of other passionate cyclists.

As mentioned before, I am a road bike enthusiast, but once or twice a year I do a race where I don the aero bike, kit, deep rim and disc wheels, as well as the aero helmet to tackle a half or full Ironman. Therefore, I am super excited (see main photo up above) to take this Smith Jetstream TT helmet out for the very first time, due to its super sleek and aerodynamic looks.

Smith Jetstream TT MIPS Helmet Unboxing

Smith certainly presents a well-designed package. It’s a nice outer box, and the protective turtle shell has an easy to open zipper to keep the helmet protected when not in use. Once opened you will find said helmet nicely tucked in there. The helmet fits perfectly into the padded slot to protect when storing or traveling. Plus, there is a space for the second clear faceplate visor to store and access. Very nice!

Features Of The Smith Jetstream TT MIPS Helmet

• Five strategically placed vents for optimal airflow
• Ionic+® antimicrobial lining offers sweat-activated odor control
• Lightweight, low-bulk single layer webbing
• Weight: (Size M, Mips®): 14 oz / 410 g
• VaporFit dial adjustment system offers 270-degree fit adjustment with the turn of a dial
• Low-profile Y-strap divider provides a secure fit to reduce wind noise and aerodynamic drag
• Magnetic visor with option of ChromaPop™ or clear lenses, ChromaPop™ lenses enhance contrast and natural color to make the details pop

The Smith TT Jetstream Helmet In Action

I’ve humorously commented before that I truly don’t want to “review” a helmet, since that would mean testing the overall crash resistance, the MIPS system, and how it will protect my precious noggin’. I like my head, I can assume Smith does extensive testing, and that their helmets are as good as you can get from a safety standpoint.

First time out, I decided to go for a ride in the Arsenal wildlife refuge here in Denver. There are usually only a few cars, so it’s relatively quiet and safe. The cars go to an area that’s off-limits to bikes to watch the wildlife including bison. For my purposes, there are four out-and-backs in the park itself, and I like to think of the overall segment, route, or course as a trident. I reckon each “lap” is about 12.5 miles. The pavement is not the prettiest and it’s rolling. That said, neither is my goal race course which has plenty of folks complaining about how rough and hilly it is.

I did three laps and was heading back out of the park to go home. It’s about 4 miles, and I am cruising at 22-25 mph. I approached a stoplight, and I had the green light. I kept going straight, and in a flash everything changed. A car turned left in front of me, and I got absolutely crushed by it. The left side of my body took the brunt of the impact and I was knocked unconscious.

My Jetstream did not explode, or show significant scraping damage. It does show a slight indent on the outside of the helmet. What I noticed is that the impact side had compressed slightly. When I break out the measuring tape out, the padding is pushed in about 1/4 of an inch. My memory of the collision is completely nonexistent. I really don’t recall the in-the-moment play-by-play version of how the crash actual happened. My recreated recollection of events is that I think I hit the brakes, and skidded sideways right as contact was made. My left hip, ribs, and shoulders took the brunt of it. Consequently, my head must have snapped into the car in a whiplash fashion. Plenty hard enough to create that kind of damage.

As mentioned before, I got knocked unconscious. The concussion has slowly gotten better, but there are days that the hazy and underlying headache is still at play. Wear that helmet, kids; It can save your precious head! The rest of the body will likely heal with time, rest, and care. The brain is a thing that is so delicate that your life can take a huge turn if not taken care of properly.

This was my head about an hour or so after the crash. Those drowsy looking eyes tell the story, for sure. Anyway, I was left with head bruises, and recurring head aches for several weeks.

Post Crash Back Out On The Bike

For my first ride back (after some good recovery time), I had to drive to my destination for a variety of reasons. I forgot my contacts, so I had to wear my regular prescription glasses without the shield. There is kind of enough room, but it’s not ideal. Quite obviously, without a visor to direct the wind up and around, the aero qualities are sacrificed. Neither here not there, I had made the time and effort, so I was going to ride nonetheless.

It doesn’t take long to figure out how this helmet wants to be worn properly and work to its aero advantages. The fit is really comfortable, and simply needs to be adjusted with the strap and the dial in the back. When I am in the aerodynamic time trial position, the wind flow around the helmet when looking straight ahead is minimal. That is what I would consider the perfect place to be, and the wind turbulence is quite minimal. Something which is easy to do is look down to rest the neck. When doing so, the back tip of the helmet sticks up, and the entire helmet naturally catches more wind.

As a result, I can hear the wind flow changing to a much louder noise. I will assume Smith has done extensive wind tunnel testing with plenty of analytical data for those that geek out on that stuff. My analysis is merely based on fit, feel, and the noise factor which is my in-depth technical version of it. In all actuality, I am truly amazed by the noticeable difference. To me that translates into numerous minimal gains the longer one can be in the correct position.

My one concern while riding is the potential overheating that can happen inside the helmet. I had literally taken this helmet out of the box, put it on, and went for a ride. I noticed that my head was getting a little warmer, and made a mental note to get a haircut. However, the only time I experience a significant temperature rise is when I would slow down or stop. No airflow equals no cooling.

The magnetic shade or glass system was a bit of a concern at first to see if it would stay put. Especially with the bumpy roads. However, three very strong magnets on the lenses themselves attach quite strongly to the helmet. They make a pretty loud pop once the magnets get close enough. This is a very impressive component of the helmet.

Ok, I thought I would ask AI to see what the difference would be between a regular bike helmet, an aero-road helmet, versus the Smith Jetstream TT helmet. Here’s the gist of it. If I switch to this sleek time-trial helmet for a full 112 mile ironman bike, I would be looking at an approximate time savings of 4-6 minutes over a regular bicycle helmet. The difference for an aero-road helmet would be in the 2-3 minute savings. Now, I’d say that’s a substantial difference just from a helmet perspective.

I do want to circle back to the venting aspect of the Smith Jetstream TT MIPS Helmet. This is one that has me a bit concerned for my goal race in what could be a hot and humid Madison, Wisconsin in September. I suppose it will be a game-day decision.

Finally, a long training day on the calendar presented me with a 90 miler. I went back to the Arsenal to fight some demons, and finish my ride from June 14th (in one piece this time). That’s 6 circuits of the trident. I started at 10:30, so I knew I’d be hitting 90 plus temperatures around noon. In doing so, I’d be riding at a time that would be somewhat equivalent to my race. Plus, training in the heat (when done so with all the right preparations) can be beneficial for hotter races. Add to that a full-on and direct sun which makes for a grueling test for riding in the heat.

I do sweat quite a lot. I usually weigh around 165 lbs., plus or minus 5 pounds. Lower 160’s is my prime racing weight when I am training with a goal race in mind. That day following my ride, I weighed in at 157.4 pounds. Dehydration plays a role of course. In turn, that forces me to give the nutrition and hydration strategy a lot more forethought as I go for longer rides. I have 7 or 8 solid rides thus far in the Smith Jetstream TT MIPS Helmet that range from 20 to 90 miles. Anything over 85 degrees is probably too hot in my opinion.

As mentioned before, head position is key, and the aerodynamic forces almost force me to be in the perfect position. The quieter the airflow, the better the aerodynamics and thus, the speed. Hence, keep your eyes looking forward with your head perched up. Dropping the head down is a very normal reaction, but aside from the safety factor, it also helps the performance of this TT Helmet

Sweat is going to be something to consider if it is hotter. Depending on the weather and what the level of exertion will be, this may be a limiting factor for use. We will see. As you are aware, there are the 3 vents in the front and 2 on the sides towards the back, and they do help tremendously. I was sweating quite a bit, and would squeeze the front of the helmet to drain the sweat from my forehead. Keeping the eyes and head up does help in this regard. When you look down, the sweat would drench the face shield which becomes quite murky over time. Visibility is key.

Preventing a dry mouth and lips is not something I would have thought of as being an advantage. However, it’s a positive thing for the Smith Jetstream TT. The mouth and lips are tucked under and protected without that direct sun glare and wind. One less thing to worry about.

Smith Jetstream TT MIPS Helmet at Ironman Wisconsin

Last, but not least, I was able to wear my Jetstream helmet for my big Ironman race. Temperatures at the start of the bike were in the high 40’s, and probably climbed to the low 60’s. Perfect temperatures for me to wear the Smith Jetstream TT MIPS helmet on race day without overheating. Wisconsin has 6500+/- feet of climbing over 112 miles which is quite a bit for an ironman. Hence, climbing up the punchy rollers and numerous climbs interrupts the full aero tuck mode quite a lot.

That said, the helmet performs masterfully. The wind slips right by without drying out my contacts or lips. Furthermore, my face and neck are kept at bay from the sun. As mentioned before, keeping in the perfect tuck position is key, and I am guided by the amount of wind noise level that whooshed by. I’d say, The Smith Jetstream TT MIPS is definitely a success. I ended up in 7th place in my age group. Not bad, but also not what I had hoped for. Next time. Funny little tidbit, is that I did beat a guy in my age group by 20 seconds. I’m sure the Jetstream is the reason!!

Final Thoughts On The Smith Jetstream TT MIPS Helmet

The Smith Jetstream TT MIPS Helmet is a really sleek and beneficial piece of equipment that has multiple benefits. It helps with protecting the head first and foremost. From personal experience, I can say that I am a benefactor from the MIPS system, and all the foam cushioning. From a performance standpoint, there are definite time saving components with the shape, the full face visors out front, along with the venting. By design, I am forced to be in the aero position prompted by the level of audible wind noise. This is certainly an investment into the overall triathlon and aero package, and I say it is a worthy one. Try it out for yourself. For more information, details, and purchase, visit smithoptics.com.