The last time I reviewed a full riding suit, I was touring with IMTBike in Europe, enjoying Klim’s updated Latitude model on an R 1250 GS (also in the March ’24 issue of BMW Owners News). I was thoroughly impressed with both the suit and the motorcycle, with the latter proving to be an absolutely stunning street bike, its prodigious ADV capabilities notwithstanding. Similarly, Klim’s latest (second generation) Baja S4 mesh suit is perfectly at home on pavement, even though it’s designed and marketed as hot weather ADV gear. Klim’s Induction/Induction Pro, Avalon and Marrakesh lines are mesh-equipped summer street kit, and for those on strictly dirt-oriented machinery, Klim offers an extensive purely off-road lineup. The Baja S4, however, takes the brand’s legendary versatility to the next level, delivering stellar performance for high-temp riding in virtually any setting. And, just as a GS doesn’t require any overlanding aspirations to be an excellent choice of motorcycle, the Baja S4 is an outstanding option for both hard-core ADV/dual-sport riders and those whose wheels will never leave tarmac. That said, it has plenty of purpose-built perks for venturing into the wilderness, too.

Ventilation

Regardless of where the Baja S4 might be worn, it wouldn’t be under consideration if the rider wasn’t concerned about managing heat. Copious ventilation is provided courtesy of large Schoeller-Dynatec mesh panels and heavy-duty Karbonite micromesh 4-way stretch zones (hence the “S4” designation) comprising most of the remaining chassis. These materials combine very high levels of strength and abrasion resistance while also allowing air relatively free passage. Compared to the smoother, lighter-weight mesh of my Induction gear, the Baja S4’s mesh looks more coarse, robust and open, and it seems to flow a tad more air. While this has obvious value for off-roading, where a rider is apt to contend with greater demands for physical exertion, what street rider would complain their mesh suit kept them “too cool” on a hot summer ride or was built with excessive durability and protection in the event of a fall? In addition, each side of the Baja S4 jacket collar has a small loop that hooks onto a tab at the collarbone, facilitating extra cooling at the throat and upper chest without letting the unzipped material flap or get pressed flat into the closed position by windblast. This is a cool (pun intended) detail I really appreciated on the non-mesh Latitude jacket. It may seem redundant on a mesh model, but it still adds significant benefit. Even the suit’s armor is thoroughly ventilated, as are the interior pockets. Finally, the jacket’s back protector compartment features a honeycomb fabric designed to keep the armor lifted slightly away from the rider’s body. A flusher interface would trap heat and block air circulation. This isn’t just a gimmick; the difference is noticeable and pleasantly surprising.

Creature Comforts

Aside from helping mitigate the discomforts associated with high temperatures, the Baja S4’s moisture-wicking mesh liner has an antimicrobial/anti-odor treatment. Fit is customizable with quick-adjust elastic straps at the forearm and upper calf, Velcro closures at the sleeve cuffs, an adjustable shock cord at the jacket hem, snaps at the leg hems, and Velcro adjustment straps with quite a bit of range on the waist of the pants. The aforementioned Karbonite stretch zones are located throughout the chassis to maximize freedom of movement (especially valuable off-road), and the knee and elbow armor pockets are also thoughtfully made of stretch mesh with adjustments for armor position to accommodate different limb lengths. With the knee armor removed, the pants will fit over most knee braces for off-road riders who want to utilize such additional protection.

Note that these pants are generously cut at the calf and hem to fit over bulkier off-road boots; they are not appropriate for tucking inside such boots, as are many dedicated off-road pants. While wearing street boots, I wished for more adjustment range to snug up the hem, but this posed no functional problem. Soft microfiber material graces the inside of the collar to prevent chaffing, and the jacket and pants can be zipped together for extra security if desired. Burly YKK zippers with glove-friendly pulls—some shaped like a stylized #1—are used throughout (the main zipper opens from top or bottom, allowing for more room at the waist if needed in the riding position), and perforated goat leather resides inboard of the knees for enhanced grip against the tank or seat and added insulation from nearby hot metal. The suit comes with provisions for a kidney belt and a 2-liter Hydrapak (Klim’s proprietary hydration system; others may also be compatible), both of which would have to be purchased separately. This is another feature included specifically with ADV/dual-sport riders in mind, but street riders get thirsty, too! And those who spend full days touring on the road know a kidney belt can help reduce lower back aches, even without all the jarring encountered on a trail.

Protection

Obviously, a riding suit’s highest priority is protection, no matter how well-ventilated or comfortable it might be. The Karbonite micromesh is a special version of 1000D Cordura nylon, the non-mesh chassis panels are 750D Cordura, and the seat is reinforced. Guarding against tearing, melting and abrasion on the road, hefty SuperFabric patches cover shoulders, elbows and knees. This unique material features a multitude of tiny ceramic plates affixed to a tough, flexible backing. Ceramic does not melt when subjected to the acutely intense heat generated by friction with pavement, and it reduces that friction—and rider tumbling—by gliding freely across the asphalt surface instead of grabbing it. Ventilated D30 brand CE Level 1 viscoelastic LP1 armor is found in all the usual places—shoulders, elbows, back, hips and knees—and the suit carries an overall CE AA rating to EN 17092-3. Klim sells Level 2 replacement armor separately for those wanting even more impact protection. 3M Scotchlite Carbon Black reflective material increases nighttime visibility while maintaining a high-tech stealthy aesthetic. Lastly, a DWR treatment repels water and may reduce some types of staining.

Speaking of water-related concerns, the atmospheric transparency of a mesh suit can be a fantastic asset in hot conditions, but then become quite a liability if the weather turns wet. Do not mistake that DWR treatment for waterproofing! Rain readily pierces mesh and stings skin underneath, adding to the misery of getting soaked. Klim sells solutions for this problematic possibility, including a lightweight, easily packable rain shell called the Forecast (redesign due early next year), or a heavier-duty, stretchy, bespoke outer layer for the Baja S4 suit, called the Enduro S4 jacket and pants ($349.99 and $329.99, respectively). Also, consider adding Klim’s Resilience jacket ($199.99) for days when the early of late hours of a ride might be chilly; its wind-blocking function takes care of this other possible drawback of wearing mesh gear. Of course, a rain shell would accomplish the same purpose, but the Resiliance is extremely easy to pack and is worn inside the jacket (also in the August ’24 issue of BMW Owner’s News).

Storage

Storage capacity is another dimension wherein the Baja S4 shines. The pants are outfitted with a large, stretchy, zippered pocket outboard of each thigh—very good, but commonplace on such gear (although these variants are unusually svelte because they rely on small pleats and fabric stretch to provide substantial volume, rather than the external gusseting of traditional “cargo pockets”). The jacket, on the other hand, is equipped with an extraordinary array of compartments. In addition to the two zippered hand pockets up front, two more unzippered hand pockets sit just behind those, and a wide zippered compartment spans the entire lower back area (perfect for lightweight rain shells, a windbreaker or change of gloves). A zippered left forearm pocket provides handy storage for earplugs, IDs, credit cards or money. It also has two details that seem to have become Klim staples—a medical alert symbol to cue first responders critical health information may be found inside (Klim will supply a free personalized plastic info card upon request) and a hidden stash pocket a bandit would likely overlook. Likewise, the Baja S4 jacket’s back protector compartment has a concealed document pocket. There are also two zippered interior pockets in the lower front of the jacket, and one interior drop pocket in the left chest area. Whether venturing out on the street or trail, this suit provides plenty of places to stow tools, gadgets, snacks and personal effects.

In Action

Now that we’ve covered the Baja S4’s elaborate construction, what it’s like to wear? What I noticed most was the extreme freedom of movement afforded by the suit’s cut and plentiful stretchy Karbonite panels. Whether swinging my leg up and over a saddle or maneuvering vigorously while underway, the ease of motion was remarkable. Airflow is good, too, especially through the relatively loosely woven Schoeller-Dynatec. The Karbonite flows air at speed, adding a lot of breathable surface area, but penetration seems to require the additional force of windblast as a lighter breeze can only be felt through the more open mesh. The jacket’s forearms are curiously tapered, creating a tighter fit than would be optimal for ventilation (and not because I possess Popeye-sized muscles there). The sleeve cuffs can be snugged down to easily fit inside long glove gauntlets; their lack of zippers make them a little more challenging to wear outside even abbreviated gauntlets, but this is no big deal. Finally, the vertically zippered hand pockets are a puzzling choice, given the similarly cut open hand pockets right behind them. Putting the zippers along the tops of those compartments would better protect against content spillage. On one hand, I applaud how quickly the suit became “invisible” while riding, due to the freedom of movement. On the other hand, I was often aware of feeling quite well protected by its extremely sturdy construction and those large SuperFabric patches, even though the suit is actually a smidge lighter in weight than my Latitude.

Purchasing Considerations

As with other Klim gear, the usual caveats about price and value apply. Top-shelf kit isn’t cheap, and discounted Klim gear can be found only very rarely (usually discontinued merchandise replaced by a newer version). Full MSRP for the Baja S4 jacket is $599.99; the pants are $519.99. (Like the concept but want a bargain? The previous generation can still be found in a limited selection of sizes and colorways. Check at klim.com and your favorite re/e-tailers.) With the full suit coming in at $1,119.98, purchase represents a substantial investment, but one I consider worthwhile for those who face serious heat during significant portions of their riding season. In 2025, that has included the vast majority of U.S. residents, and it may be even worse in the future. Hyperthermia is a potentially deadly malady, not only because overheating can lead to organ failure, but also because a cooking brain’s ability to pilot a motorcycle may be compromised long before the general bodily effects become obvious. Temperature management is crucial to both rider safety and comfort. A lot of cooling can be accomplished with zippered vents, especially when paired with a controlled-evaporation base layer, but nothing matches mesh’s sheer volume and ease of airflow. Klim’s Induction/Induction Pro, Avalon, and Marrakesh lines are lighter, less expensive and work beautifully on the street (see my review of the Induction jacket—an online exclusive!), but they don’t deliver the Baja S4’s durability, protection and advanced feature set. That’s a trade-off each consumer must evaluate for themselves.

The current Baja S4 jacket and pants are available in four color combinations and a wide range of sizes, including regular, short and tall variations. Given this garment’s mission of beating the heat, I chose the lightest overall tint to reflect the most radiant energy on sun-drenched summer days; the other options are more visually exciting with a few brightly colored accents. And if you’re an ADV rider who loves matching gear, take a look at Klim’s Baja S4 gloves ($89.99), which seem a bit more biased toward off-road use. As for sizing accuracy, the pants fit exactly as expected. However, as I found with the Latitude jacket, Klim seems to be tailoring their jackets more generously in the current era. Whereas my assortment of older Klim jackets have always been mediums, I needed to drop a size and go with a small in the Latitude and Baja S4. While the latter is ever so slightly snug on me, the stretch panels ensure there’s still zero resistance to movement in all planes. Prospective buyers should check Klim’s sizing charts and consult a sales representative regarding any questions.

Klim Baja S4 Jacket, MSRP $599.99. Available in Slate Gray/Peyote, Monument Gray/Black, Hi-Rise/Nightfall Blue, and Black/Fiery Red. Sizes SM-3X.

Klim Baja S4 Pants, MRSP $519.99. Available in colors matching the jacket. Sizes 30-44 Regular, 30-40 Short, 32-38 Long.