Internal Rim Width (measured): 35 mm
External Rim Width (measured): 40 mm
Blister’s Measured Weight: w/out valves or tape:
- Front: 860 g
- Rear: 966 g
- Total: 1826 g
Test Bike: Santa Cruz Nomad MkIII, Large
Reviewer: 5’8” 160 lbs.
Test Locations: Park City, UT; Umpqua, OR
Test Duration: 26 rides
The Loaded Precision X40 wheels are a particularly interesting wheelset. First – they come in at a competitive weight for a carbon wheelset at a price that undercuts groups like ENVE and Reynolds by hundreds of dollars, and second – the rims are quite wide.
There is a growing ‘Wide is Right’ tribe in mountain biking at the moment. The stated advantages make sense – wider rims provide more support to a tire and increase the volume of the tire, allowing a rider to run less pressure and/or get less tire deflection over bumps and through turns. The counter argument is that wide rims can be heavy, the advantages aren’t as big as stated, and that a wider rim creates a squarer tire profile that is slower to initiate turns (tire manufacturers are working on that last one though – see Noah’s Maxxis Wide Trail review).
Like most debates, both groups are right about some aspects and really, it is a balance between the two camps. Rim width will end up being a personal choice to a large extent.
However I can tell you where I fall after my experience with the Loaded Precision X40 wheels, and if they are an option you should consider when you next buy wheels.
The X40 wheels are 40 mm wide on the outside and 35 mm wide on the inside. There are a few groups selling 40 mm internal width rims for 2.3-2.5” tires, but those are pretty rare. 35 mm wide rims are less exceptional than they used to be, but are still quite wide for non-plus tires.
Loaded advertises that they use a Carbon Knitting Technique that is proprietary which improves impact and fatigue performance. They also list that they use unidirectional fibers. This is on par with most carbon construction in the bike world. Additionally, they list Nano-Elastomer Infused Resin, and state that it improves durability and impact absorption. Sounds great.
Loaded shows faith in their construction with a lifetime (5 yr) warranty against defects and a 40%-off-MSRP crash replacement policy.
The rim is hookless, a design that is supposed to improve rim impact resistance. The rim also used standard nipples. This makes spoke replacement much easier than on an internal nipple design like ENVE’s. However, it does result in a slightly larger hole in the rim. Advertising copy will tell you that a smaller hole in the rim is stronger. That makes sense, but having broken a few carbon rims and seen others break, I have yet to see one that broke at a nipple hole.
The Wheel Build
The X40s have 32 double butted j-bend spokes. That high of a spoke count is a rarity on a carbon wheelset and it definitely makes for a stiff wheelset. I like that the spokes are j-bend. They are definitely still easier to find at bike shops than other designs. The nipples appear to be alloy. That could react with the carbon and corrode, but I really doubt I’ll see that in dry Utah.
When ordering, you get the choice of black, gray, silver, gold, red, green, or blue stickers. Oooo, colors. You should be able to complement just about any bike.
The hubs are a pretty standard OEM offering from Asia with 36 points of engagement and the option for either Shimano or XD freehub bodies. They do only come in 142 mm spacing. But they were solid for me, with no popping, and really positive engagement. Looking at the freehub, the pawls are quite long, with fairly robust springs. The design seemed much more robust compared to another asian-produced hub I had. At the same time, the design seemed more robust. They rolled pretty well too.
Mounting and Initial Setup
Getting tires on and/or off these rims is hard. Not impossible, but very hard. I don’t usually use tire levers but I need tire levers or a helping hand with these. The difficulty is that the groove in the middle of the rim (that allows some slack in the bead) is so far inset from the edge of the rim that it is hard to get the bead over to it.
However, I was able to seat a few different Maxxis and WTB tires with a floor pump. And the hold on the tire bead is tenacious. That was particularly apparent on an occasion when I had to ride out a trail on a nearly flat tire. Even with just a breath or two of air in the tire it stayed on the rim, even through tight, hard corners. So, once you get a tire on there, you are likely to be very happy with tire retention. I haven’t ridden anything else that holds a tire quite so firmly.
The Loaded wheels are listed as 1580g +/- 15 g, but they came in significantly heavier when I weighed them at 1826 g. 1580 g is extremely light. 1826 g isn’t. I would have been very frustrated to pay for the wheels and receive them to find out there was that discrepancy. I imagine there is a story to tell regarding the weight – maybe an inline change to layup.
Stiff. These wheels are stiff. I can’t emphasize that enough. Not only is there little flex in the rim or wheel build, but they definitely do add support to tires and reduce tire deflection. The wheel is stiff both vertically and laterally. I’d be stumped if you asked me to say in which direction the wheel is stiffer.
It took me a bit to get used to how they ride given the stiffness. They just don’t load up into corners and then spring out of them like other wheels. At first that feels odd, but once I got used to it I found that I could steer more precisely and confidently through corners.
The stiffness was definitely a benefit in rock gardens. I found that my bike would track better and avoid deflecting off rocks.
The wide rim squared off tires, particularly the already relatively square Maxxis High Roller II 2.4 and the Maxxis Minion SS. The squarer profile made them roll very slow and made them feel weird on the road. Initiating corners on pavement felt really strange and a bit unstable because you’d end up exclusively on the cornering knobs. The rolling resistance difference wasn’t as apparent on dirt, but definitely still present. The cornering feel was much better though. I couldn’t ease my way into turns, but I could throw my bike into the turn and the tires would bite and carve like they were on rails.
I eventually mounted up a 2.5” Maxxis DHF Wide Trail tire and found the profile to much better match a more normal tire profile on a narrower rim. This helped solve the rolling resistance issues, but took away from some of the ‘on rails’ feeling in corners. I could still feel the reduced tire casing roll from the wide rim though.
A lighter rider might find that the wheel stiffness and square tire profile takes a lot of the feel out of a bike, and a heavier rider might find the stiffness less noticeable. As it was, at a 160 lbs, I came to appreciate the stiffness.
I didn’t get a full season on them, but so far they have held up like champs – and I have a bit of a record of destroying rims – particularly on the rear of my bike. One of the best indicators I’ve found for wheel build quality is if a wheel holds tension through the first few rides. It indicates that the builder balanced spoke tension and took efforts to reduce spoke wind-up. I haven’t had to true or tension the wheels since I’ve had them.
I’ve got a couple scratches on the side of the rim. I also pinch flatted a tire on them without any visible damage to the rim.
Vs. Reynolds Black Label 27.5 AM
The X40 wheels are much heavier, but much stiffer. The choice is easy, if I have extra cash and I want to cover serious ground I’d take the Reynolds in a second. If I want to crush laps in the park I’d grab the Loaded Precision Wheels.
Vs. Nextie ASYM 32 rim (32 spoke)
The Loaded Precision X40 rims feel very similar to the Nextie wheel build I’m on now. Stiffness is comparable and build quality looks very similar. I do find that I prefer the slightly narrower 32 mm inner width of the Nextie rims. It was much easier to get tires to seat on the Loaded Precision wheels, but most of the issues on the Nextie rims came from the valve hole coming through on a sloped part of the rim due to the asymmetry.
The Loaded Precision X40 wheels aren’t as light as they advertise, but they are a good value for someone wanting a carbon wheel and not wanting to buy Light Bicycle or Nextie rims and go through the trouble of having them built up.
The hubs pleasantly surprised me and the durability has been good so far. I’d recommend these to anyone looking for a very stiff, wide carbon wheel.