Jack the Bike Rack Review

We first reported on Jack the Bike Rack back in June. At the time, the makers at UK-based WholeGrain Cycles already had several working prototypes being tested out in the field, and it caught our attention as a versatile solution for gear hauling and basketpacking without needing to worry about bosses, eyelets, or tools to attach to your bike. As long as you’ve got sufficient clearance above the front tire, there’s a strong likelihood that Jack can work for you.

I recently received a pre-production version of Jack to test out prior to their upcoming Kickstarter launch. So, while the version you see in the photos below won’t look exactly like the final version, the functionality will remain the same. The finished racks will have some cleaner welds and fewer heat marks, and they will be acid-dipped and clear coated. I’ve done my best to try Jack out in a variety of different ways to get a good feel for what it does best, including several different styles of bikes, as a platform for basket-packing, hauling pizzas, and even as a way to carry a packraft.

Jack is made from a single piece of cold-formed 304 stainless steel rod with a 420-denier fabric platform. Two high-strength straps are used to attach it to the bike, cantilevering JACK over the front wheel. One threads under the stem, which holds the rack up and keeps it from rotating down toward the tire, and the other goes around the steerer tube, which keeps the rack from rotating upwards. The rack is officially rated for loads up to 5kg (11 pounds), but according to WholeGrain, it can carry significantly more than that. Jack comes with a removable fabric base, shims for 31.8mm and 25.4mm bars, four different stem load straps, an adjustable steerer tube strap, and two 1.2m bungee straps with a snakehead buckle and carabiner.

Compatibility is pretty much as universal as it gets, requiring no special mounting points or modern features. It’s compatible with both metal and carbon handlebars, requiring 10mm of free space on both sides of the stem. At least 225mm (~9″) is required from the centre of the handlebar to the top of the front tire (measured perpendicular to the ground), and it works well with rigid and suspension forks. The stem angle also plays a role in compatibility and works well with 0° to +40° stems, or negative angle stems that are fixed to the steerer tube. Jack works with both threadless and threaded quill stems.

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Components and Installation

The various components sent along with the rack are functional and well made. The four included stem load straps, which loop under the stem, are made from three sandwiched layers of webbing—a design that immediately reminded me of a webbing dogbone used by climbers. It turns out they are made from climbing-grade webbing and can take in excess of 300 kilograms of dynamic loading. I’ve been loading Jack up with some pretty serious weight, and I was never worried about the stem load strap failing. The other strap has a stainless steel cam-lock buckle for quick adjustments, which is especially useful when tensioning the entire system during setup. Between the two straps, it’s also super easy to install or swap between bikes, since no tools or finicky hardware are needed.

Installation is quite straightforward. The included bar shims snap easily into place on the upper curved section of the rack, and with the shims installed, it’s a matter of figuring out what length of stem load strap will position the platform near parallel to the ground once some weight is added. I did this by pushing my elbow down onto the front end of the rack, making sure the upper strap wasn’t too tight for the rack to get into position. There are two small hooks positioned just behind the handlebar, where the stem load straps attach, holding the rack up and away from the front wheel. With a little bit of a push, the rack snaps directly on the handlebar, on either side of the stem, and the upper strap can be attached in place. The lower steerer tube strap has an upper anchor point for bikes with spacers under the stem, and a lower position for those without. The lower anchor point results in less flex in the entire system, which is great for riding singletrack or over bouncy terrain. All that’s left to do is preload the rack by giving it some weight with your arm, and tensioning up the steerer tube strap’s cam lock buckle. Jack is good to go!

Compatibility

Jack might just be the only universal-fit rack that actually lives up to those claims. The beauty of Jack’s design is that no frame or fork mounts are required. As mentioned, WholeGrain Cycles suggests having a minimum of 225mm (~9″) of clearance between the top of the handlebar and top of the front tire. Although, on some setups, you’ll be able to get away with a little less. The bar clamps work with stems with 35-50mm wide faceplates and require just 10mm of clearance on either side of the stem to mount securely. Unfortunately, Jack isn’t compatible with 35mm bars at this time.

Because of the lower retention strap anchor points, it doesn’t matter if you’ve got a lot of spacers under your stem or it’s slammed against your headset. As long as you’ve got clearance above your front tire and you’re not running 35mm bars, Jack will likely work for you. While Jack’s compatibility is the real selling point, the lack of adjustment does mean the load will always sit at the same height in relation to your bars, which could up being quite high on some bikes. The higher load was much more noticeable on the Bassi Hog’s Back, for example, compared to the Panorama Taiga I tried it on. So, while Jack will work on most bikes, some will handle heavier payloads better than others.

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While out Jack-Packing

While I’ve only had Jack for a short while, I’ve managed to get out on a handful of loaded rides to see how it works. Beyond the high-quality construction and simple installation, a few other things caught my attention right away. First, due to the lack of mechanical fixing points, Jack does have some side-to-side play. It’s not enough to feel insecure or poorly fitted, but it’s quite obvious when riding around without a load or when the rack isn’t properly preloaded. Speaking of preloading, it’s important to use the right length of stem load strap that allows you to properly weight the rack and tighten down the lower retention strap. On the bikes I set Jack up on, I aimed for the platform to be parallel or tilted slightly towards the front of the bike, when preloaded, and that seemed to work well. The amount of play can also be exaggerated if your handlebar tapers or bends quickly away from the stem clamping area, or if your stem faceplate doesn’t have straight sides, allowing the rack’s spacers to pivot around these points. The good news is, most, if not all, of this play is non-existent when Jack is loaded up with some weight, and it was never an issue while riding. All I ever noticed was a slight amount of vertical flex in the system, which is expected for a tool-free rack.

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I found that the height of the rack hit a sweet spot for everyday use, whether you’re bikepacking, commuting, or using it as a platform for a basket. Jack positions the weight lower than the majority of handlebar roll style bikepacking bags and does so without pushing the load too far out in front of the bike. The different stem load straps and pre-load design allow each user to dial in the position of the rack depending on the bike and preference, but overall I’ve been quite happy with the design. Sure, short folks still might not have enough clearance, and tall people with high handlebars might feel the rack doesn’t position the load low enough, but I think WholeGrain Cycles did a pretty good job at making it nearly universal.

After switching it between a few different bikes, I discovered that head tube angle also plays an important role in how Jack is set up. Slacker head tube angles, like the 67° on the Panorama Taiga, may require a shorter stem load strap to help pivot the rack away from the head tube and fork crown. While this isn’t an issue in itself, it does mean a flat platform won’t be achievable on all bikes. I was just barely able to squeeze Jack in above the fork on the Taiga, and with heavier loads, I’d probably be running the small stem load strap to ensure proper clearance. However, I was still able to load Jack up with a Kokopelli Rogue R-Deck packraft and paddle, at around 10lbs (4.5kg), with great success. Since that type of load is at the upper limit of what WholeGrain recommends, there was more vertical flex, but the setup stayed fairly stable on some low-speed singletrack. Plus, due to the flared design of Jack, a big hit wouldn’t necessarily mean the rack would come in contact with the bike, which is an added bonus. I wouldn’t have a problem loading Jack up to max capacity when riding gravel, smooth doubletrack, or while commuting—but if rowdy, heavily loaded singletrack is your poison, there might be better options out there. I also noticed that the lower retention strap felt a touch short at times, so I quickly subbed in my beautiful CNC-machined Austere Manufacturing cam-lock buckle.

While I only had a quick chance to strap on a few top-loading handlebar bags from Bags by Bird and Roadrunner, the design quickly proved itself effective as a handlebar bag support as well. This makes it a great option for those without much clearance above the front tire or for anyone whose front bag is always rubbing their tire. Since the bar hooks are positioned tight against each side of the stem, it leaves plenty of room for handlebar bag straps or other bar-mounted accessories.

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• Load Capacity: 5kg (11lbs)
• Dimensions: 230 x 225 x 280mm (HxWxL)
• Material: 304 Stainless Steel, 420-denier fabric, stainless steel buckles
• Weight: 700 grams (rack, retention strap, ‘M’ load strap, fabric base and 31.8mm spacers)
• Place of Manufacture: China
• Kickstarter Price: £58 (~$80 USD)