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Primal QX5 Inertia Jersey & Bibs Review

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The next best thing to a new bike or wheels is new kit. So I was thrilled when the PEZ asked me to review the Primal QX5 Inertia jersey and bib shorts. As a diehard roadie and former early 90s era racer, I’d always thought of Primal gear as either for mountain bike riders or more casual road riders. Their designs are largely fun or even edgy, but not as EuroPro as my taste leans.  I remember them as one of the first companies to have more “looser fit” cycling clothing – perfect for those cyclists who were more self-conscious about wearing skin tight lycra.


Primal QX5 Inertia Jersey & Bibs


But that was then and this is now. Primal still has fun and edgy stuff – such as their Evo Series for men and women, as well as their Limited Edition and Artist Series. And, to be honest, I like a lot of it because it’s fun and different. Also, this sort of kit has become more “mainstream” thanks to a more “relaxed” attitude about cycling brought on by the popularity of urban cycling and cyclocross. But Primal has also ventured over to the Dark Side with kit that is decidedly more race roadie and by sponsoring the Primal-Audi Denver amateur elite team. Enter the QX5 kit, which is the team’s kit.


Primal QX5 Inertia Jersey & Bibs


Inertia QX5 Short Sleeve Jersey - $150
The Inertia QX5 is Primal’s latest and greatest jersey. Predominantly black has become a common and popular theme with a lot of modern jerseys (especially among the Brits) and the Inertia QX5 follows this script. Although – thankfully – it’s not murdered out black kit. Primal uses shades of black and gray with a digital graphic design in a horizontal pattern across the front and back so that it’s not monochromatic black and a little more visible. And green down the front along the zipper line and on the sleeves gives it a touch of color and pop to catch your eye. Maybe not as “wild” as some of Primal’s other designs, but not boring or dull either. If you want to design your own QX5, Primal makes it available as a custom design for your team.


Primal cycling jersey


Looks aside, here’s what Primal has to say about it:
"The InertiaQX5 was one the greatest fighter jets known to man. It was fiendish in the face of battle and faster than a speeding bullet. On its last airborne mission, the pearly aircraft disappeared. Rumor has it that the plane plunged deep into the sea, meeting a Neptunian fate with a lost watery grave. While the story of the InertiaQX5 has never been truly solved, the mysterious jet is still seen to this day. It circles around swiftly, leaving billowy white contrails as it vanishes into the clouds."


cycling jersey


Get past the marketing-speak and what you have is modern, high tech race jersey. The fit is most definitely race (what Primal calls “pro tour fit”). According to Primal’s sizing guide, a size small is for someone with a 36-38 inch chest, weighs 120-145 pounds, and stands 64-68 inches tall. I’m an ectomorph (that’s science-speak for skinny guy) who fits this description and the Inertia QX5 was about as skintight as skintight gets – a lot like wearing a skinsuit. In other words, exactly how you would expect a race fit jersey to fit. So if you want or need a more forgiving or flattering fit, these are not the droids you’re looking for.


cycling jerseys


The sleeve compression band is 60mm wide and the silicon gripper grid is 35mm wide

Adding to the form fittingness of the Inertia QX5 jersey are compression sleeves with silicon “grid” on the inside of the sleeves for a snug fit around your arms. In fact, if you have bulging biceps instead of skinny ectomorph arms like me, getting your arms into the sleeves could prove to be a bit of a challenge. And the sleeves are a little bit longer than most of my other jerseys, but longer is the current trend in pro peloton fashion. There’s also a silicon gripper around the elasticized bottom of the jersey helps keep it from riding up in the back. Speaking of the back, there are the traditional three jersey pockets in the back but the tops of the two outside pockets are angled down rather than straight across. The idea being that this makes it easier to reach in and out of the pocket while riding. The pockets aren’t quite as deep as the pockets on most of my other jerseys, but I didn’t suffer from any fears of anything falling out of them while riding. Still, the Inertia QX5 is billed as a race-level jersey and would be better with deeper pockets that you can cram stuff into. By definition, smaller pockets — even if just slightly so — mean the ability to carry less stuff. More so since the slanted side pockets make them effectively smaller. The one thing the Inertia QX5 doesn’t have that a few of my other jerseys have – and that I really like – is a smaller zippered pocket to put small stuff in that you want to keep more secure.


cycling apparel


A full waistband silicon gripper helps hold the jersey in place.


cycling apparel


Do the slanted pockets that make it easier to access the stuff you’re carrying count as marginal gains?

Not only is the fit aero, but the material is also aero. The Inertia QX5 has what Primal calls Vortex panels on the front, back, and sleeves. These are dimples arranged in a honeycomb-like fashion. Think golf balls or Zipp wheels. The dimples are supposed to reduce aerodynamic drag by allowing passing air to breakaway from the jersey surface more easily, which smooths airflow and creates less wake. I'm not an aerodynamicist, so I'll have take Primal at its word that the Inertia QX5 is faster than all my other jerseys. If only I were that fast.


bike jersey


Vortex material with honeycomb-like dimples is supposed to reduce drag

The jersey material is also very light and very sheer. If you hold the jersey up to a light, you can actually see through the honeycomb-like structure of the Vortex panels. It’s not open mesh that air can flow freely through, but it’s pretty darn close. Needless to say, the Inertia QX5 is not a cold weather jersey but should be up to the task of being as comfortable as comfortable gets during the dog days of summer.


bike jerseys


Primal claims 135 grams for a size small jersey and my size small weighed in at 139 grams on my scale

Also helping you keep cooler in hot weather are mesh side panels and on the bottom of the sleeves. And as is de rigueur for a modern race jersey, a full length YKK zipper (sort of the industry standard for zippers) gives you a way to create even more air flow and let you do your best Tommy Voeckler impersonation with your jersey fully unzipped, face in full grimace, and tongue hanging out as you grind up your favorite climb.


bike jersey


The honeycomb of the Vortex material is more apparent on the inside of the jersey – in definite contrast to the mesh side panel material

If you zip the jersey up, one thing you’ll notice is that the Interia QX5 doesn’t have a traditional “mock turtle” collar. Instead, it’s more like a crew neck t-shirt collar – another indication that this is primarily a hot weather jersey. And the back part of the collar is the same mesh material as on the side panels.


mens cycling apparel


Vortex on top for speed, mesh on bottom for cooling.


mens cycling jerseys


For the PEZ zipper aficionados, a YKK zipper … the gold standard of zippers

Inertia QX5 Bib Shorts - $250


men's cycling bibs


The Inertia QX5 bib shorts take their styling cues from the jersey, with the same black and gray horizontal pattern on the side panels with a wide green band around the leg opening and on the back of the bib at the base of the back. Together, the jersey and bibs have a not too flashy, but just enough to make a statement, look that will stand out in a sea of black kit.


cycling bibs




cycling bib


Like the jersey, the Inertia QX5 bib shorts are race fit. You definitely don't just slide them on, especially with the silicon gripper grid on the inside of the compression leg bands. And like the jersey sleeves, the bib shorts legs are slightly longer.


cycling bib




cycling apparel


The compression bands and silicon gripper grid are the same on the legs is the same as on the jersey: 60mm and 35mm, respectively

The material Primal uses for the Inertia QX5 bib shorts is Resistex® Carbon fabric that claims it "lowers the concentrations of lactic acid, improving the circulation of the blood and oxygenates the cells."

Resistex® Carbon also "speeds up the evaporation process of perspiration, slows down the formation of humidity on the skin, and keep the temperature constant." Believe what you want. Both are claims that I can't confirm. Suffice to say that the material feels very comfortable against my skin and, like the jersey, I don't doubt that it will do well when the days start to hot up.

Interestingly, the Inertia QX5 bib shorts are rated at SPF 50, which may be another property of Resistex® Carbon because Primal doesn't say the same SPF 50 protection for the jersey and it's not a material Primal claims it uses for the jersey. So while the jersey has aero dimples, the bib shorts don’t.


cycling apparel


Primal claims a size small pair of bib shorts weighs 240 grams and my size small weighed in at svelte 183 grams!

The bib part is not unlike a lot of other bib shorts in terms of the way its designed and cut: a semi-wide full length Y-back section and a scooped front that on me came down to just above my stomach. The bib straps were comfortably wide. A lot of manufacturers use a white material for the bib part of bib shorts, but Primal chose to go with black – and the material is a mesh to help you stay cooler. Unique to any of my other bib shorts, the Inertia QX5 has a race radio pocket. Not that I have any need for a race radio, but I did do a ride with a Motorola FRS 2-way radio that I have lying around tucked in the pocket and it was surprisingly comfortable. If you have small stuff you want to keep more secure and don’t need access to while riding, the race radio pocket could be a good place for that. However, the race radio pocket is at almost the same level as the jersey’s middle rear pocket so too much stuff in both could be too much bulk. I feel like it would have been better to position the race radio pocket higher up so that’s not an issue.


cycling bibs


If you have need for a race radio, the Inertia QX5 bib shorts have a place for one


cycling apparel


Is that a race radio or are you just happy to see me?

Of course, the most important part of any bike shorts is the chamois. Primal uses a 4-way stretch, four density material for what it calls the HX8 Carbon Italian Chamois. Honestly, I don't know what the carbon part of the chamois is, but can tell you that my butt and other parts were perfectly happy riding in the Inertia QX5 bib shorts (as a point of reference, I ride a fi’zi:k Kurve Bull saddle, which they no longer make, that has next to zero padding). The HX8 chamois padding is relatively “cushy” without being too thick or soft so that it doesn’t feel like a diaper. Like a lot of other chamois designs, the padding is thickest at the sit bones and becomes less dense moving outward to the edges of the chamois. Unlike many other chamois, there isn’t a pronounced split/gap along the perineum. Also, the HX8 chamois isn’t dimpled or perforated for airflow/cooling, but is antibacterial and antimicrobial.


cycling apparel


The HX8 chamois uses a four density material that is a nice balance between firmness and cushioning, and should be comfortable for long days in the saddle

The Proof is in the Ride
Ultimately, what matters most about any bike kit is how it feels and performs on the bike. At least for me, the skintight fit of the Inertia QX5 jersey and bib shorts was comfortable – your mileage may vary. It never felt constricting or restrictive – making it easy to move around on the bike. Although the honeycomb of the Vortex material is textured, it didn’t rub and wasn’t abrasive. And whatever the technical properties of the Resistex® Carbon material in the bib shorts, it was soft and smooth against my skin. And despite all the different panels on the both the jersey and bib shorts, none of the seams were irritating. I was a little worried that the compression bands and silicon gripper on the sleeves and legs might make them feel too tight. Instead, it felt pretty natural and I can’t help but wonder if they impart some of the same effect as compression sleeves – increasing blood flow and reducing muscle fatigue.


primal cycling apparel


In my part of the world, we’re just now beginning to experience warmer temperatures – including an unusually hot April day up to 90F or so – and I haven’t had any problem staying cool enough wearing the Inertia QX5 jersey and bib shorts. One thing I really noticed is that the Vortex material does an excellent job of wicking away sweat. Although nothing short of actual air conditioning will keep you cool and comfortable during the heat and humidity of Washington, DC summers, I’m confident that the Inertia QX5 kit will be as cool as cool gets when it’s hot fun in the summertime.

My longest ride in the Inertia QX5 bibs has been 40 miles, but I’ve ridden in enough different shorts and done enough long rides for my butt-o-meter to tell me that they kit will be good to go on longer 60-80 mile rides. I don’t ride much longer than that these days, but I don’t see – or feel – any reason why it wouldn’t be good for 80-100 miles based on the density and firmness of the chamois. So if you’re into gran fondos or sportives, the Inertia QX5 kit should be up to the task if you are.

If you are a performance-oriented roadie – even if you’re not a racer – then you’re the rider Primal designed the Inertia QX5 kit for. Primal may not come to mind immediately if you’re in the market for high tech race kit, but it’s more than worthy of consideration. The Inertia QX5 kit isn’t cheap, but the same is true for other manufacturers at this end of the spectrum. So you may be paying top dollar, but you’re getting top shelf stuff. Primal’s roots may be mountain bikes, but they definitely hit the mark for more serious roadies and wannabe EuroPro racers with the Inertia QX5 jersey and bib shorts. Chapeau.

NOTE: If you buy both the Inertia QX5 jersey and bib shorts, Primal currently has them on sale together for $360.
• Check prices for the QX5 Intertia Jersey on
• Check prices for QX5 Bibshorts on here

primal cycling apparel

With the slightly longer sleeves and legs, the look of the Inertia QX5 kit is definitely current fashion EuroPro

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PEZ contributor Chuck Peña is a former weekend warrior racer who now just rides for fun, but every once in a while manages to prove Fausto Coppi’s adage true: Age and treachery will overcome youth and skill. He lives in Arlington, VA with his wife (who is his most frequent riding partner), his daughter (an aspiring junior golfer who takes great joy in beating him all the time), and their dogs. You can follow him on Twitter @gofastchuck



About PEZ Cycling News"What's cool in pro cycling" defines our content and means as much now, as it did when I started PEZ in 2002. is a group of internationally-based pro cycling fans dedicated to publishing original, credible, and entertaining articles, photos, features and reviews centered around the sport of elite level professional cycling.



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