With the growing popularity of e-bikes, wheel companies, such as WTB have started to manufacture e-bike specific mountain bike wheels. But what is different about them, and why should eMTB riders consider buying them? After unboxing and riding the HTZ i30 wheels for some time, I am convinced WTB didn’t just slap an “e-Bike” sticker on them. They built one of the burliest wheelsets I have ever ridden.
WTB HTZ i30 wheelset stiffness
Right out of the box these wheels feel hefty. Each wheel felt stiff and robust just as much as the spokes. Interestly, they don’t have that carbon wheel stiffness but rather a burly and robust feel only a thick-walled alloy wheel can give.
These feature 20% thicker rim walls compared to the brand’s KOM Tough Enduro wheels. The HTZ i30 wheels have an asymmetric spoke offset that helps balance tension and creates a more stable wheel while the symmetric outer rim profile distributes impact forces evenly. Hit after hit, the wheels stayed trued, giving a “Hulk Smash!” feeling that inspired me to roll through almost anything I pointed my e-bike toward.
To increase rigidity further, WTB added one I-Beam vertical support within the inner rim cavity. The I-Beam is not visible to the naked eye unless you slice through the rim, but this type of beam support can also be seen in their KOM Tough gravity wheels. WTB claims this beam support is thicker than on any other WTB rim, drastically increasing the strength and rigidity of the HTZs.
The WTB HTZ i30 wheels are built up with 32, 13-gauge butted spokes in each wheel, and each spoke is 2.3mm thick at the hub and 2.0mm thick at the opposite end. This helps to counteract higher braking forces and increased motor torque distribution with each pedal stroke. Stiffer spokes can reduce the chances of them snapping, sure, but I didn’t really notice the increased motor torque distribution. I’m just not that picky with my e-bike, yet.
WTB HTZ i30 hubs
You can’t have all of these robust wheel parts without a purpose-built e-bike hub. With some e-bikes putting out as much as 700w of peak power or 108Nm of torque on command, you’ll definitely want a hub that can withstand that much force.
The freehub body is made from heat-treated steel which reduces the chance of pawl socket failure. The 42-tooth drive ring and 6-pawl ratchet system gives simultaneous engagement of all pawls compared to other offset 6-pawls that only have three points of engagement. When I’m on an e-bike, I typically don’t really notice or care for pawl engagement like I would notice on an analog bike, but it makes sense to have even engagement to help distribute pedaling forces and prevent slippage.
In addition, a traditional 12mm thru-axle will fit right through the axle sleeve, which has had its outer diameter beefed up from 15mm to 17mm in thickness to increase durability and reduce axle flex. This stiffness is mostly noticeable when cornering with the help of every other beefed up part in this wheelset. To improve wheel life longevity, the rear hub has five double-stacked sealed Enduro bearings to keep you rolling longer. Buyers can pick from HG, XD, and MicroSpline freehub bodies.
Heat Sink
What caught my attention the most about these wheels was the rotor mount heat sink. As a computer geek I know exactly what a heat sink is and thought to myself, “geez why didn’t I think of this?”. According to Google, “a heatsink is a passive heat exchanger that transfers heat. The heatsink is typically a metallic part which can be attached to a device releasing energy in the form of heat.”
In this case, it’s specifically placed behind the 6-bolt rotor mount to dissipate heat from the rotors. WTB claims this heat sink can help dissipate heat up to 10% better on long descents. Heavier riders like myself or bikers riding heavier bikes will know that any way to increase braking power is greatly welcomed.
Ride quality
There is no denying these wheels are burly, hefty, bulky, bombproof, or whatever you want to call them. These wheels are overbuilt on purpose: for e-bikes but also built for riders who demand longevity and reliability from their components. Ride after ride, boosting through the climbs and smashing on the downs, I felt confident that every part of the wheels would hold up to the abuse.
If you’re like me, sometimes when you purchase a new fancy set of wheels, you want to avoid “sending it” or landing a certain way that may compromise your wheels. That wasn’t the case with the HTZs! In fact, they made me want to keep smashing through rocks, roots, ruts, and so on. It’s a wheelset to throw on your bike and forget that it’s there. You’re getting a lot of peace of mind with these.
The robustness and stiffness these wheels offer is like no other, and the flip side is a loss of handling playfulness at low to mid speeds. This characteristic may very well differ with each rider and may not be a negative thing for some of you, but it’s worth noting as they changed how my all-mountain midweight e-bike felt at those speeds. The HTZ i30 wheels feel heavy rolling, in part due to the way the wheels give tires a consistent, planted feel at lower air pressures. They do seem to liven up at higher speeds if you ease up on your braking.
The 6069 aluminum alloy 29er front wheel I tested weighs 1,235g while the rear, SRAM XD wheel weighs 1,427g, totaling 2,662g for the pair. But you weren’t expecting low weight numbers, right? It’d be ridiculous of me to pick on this wheelset for its weight. WTB prioritized durability and sought out to create wheels that are bombproof without ever setting a target weight. You can find cheaper alloy wheels that are plenty heavy. The HTZs didn’t eat and hibernate, they went to the gym to gain muscle where it matters.
If you’re running something similar to a Double Down casing tire the tire installation and removal process is made easier thank to WTB’s “On-Ramp” rim valley. Just make sure to mount both sides of the tire on the short side of the rim.
Pros and cons of the WTB HTZ i30 wheels
Pros
- Hand-Built in California/Italy
- “On Ramp” makes tire install and removal easy
- Excellent value
Cons
- Faster downhill speeds required to liven them up
- Overbuilt for lightweight e-bikes
Bottom line
With the popularity of lightweight e-bikes, a robust wheelset like the HTZs might take away from what those bikes are designed to do, which is to be fun and playful. If you have a mid-weight or heavyweight e-bike with a big battery, powerful motor, 38mm fork, and long-travel shock set up to give trails a piece of your mind, then you might as well upgrade your wheelset.
Could WTB have made these out of carbon? Maybe, but with most heavy-hitter carbon wheels out there weighing almost the same as their alloy counterparts, carbon isn’t suited for every application. Paper beats rock, but rock beats carbon. We know alloy wheels can be damaged too, but at $329.95 for the front wheel and $439.95 for the rear with a 2-year limited warranty and hand-built in California/Italy, surely e-bike riders will be amped to give these wheels a try.
- Price: $329.95 front, $439.95
- Buy from Worldwide Cyclery.
2 Comments
Mar 13, 2023
Mar 13, 2023