Back in 1990, when the first hit the cycling scene, Spinergy’s wild-looking Rev-X carbon one-piece wheels quickly became all the rage. At the time, the market was comprised of no-flash, shallow aluminum rims and steel spokes, so the Rev-Xs were definitely ahead of the curve in the looks department. From roadies to mountain bikers to triathletes, you could find a pair on just about any and every type of bike. Twenty-one years later, Spinergy is still turning out unique designs, albeit maybe not as dramatic as the Rev-X.

TECH
Spinergy’s reputation for making a wheel that stands out holds true with their Stealth PBO. The most distinguishing feature of the Stealth wheels are the3mm-diameter spokes. Although they look similar to Mavic’s Tracomp tubular carbon spokes, unlike Mavic’s carbon creations, each Spinergy spoke is made up of 30,000 strands of polyphenylene benzobisoxazole fiber (sounds like a diet-soda ingredient, doesn’t it?), which are incased in a water-resistant, UV-proof composite. The PBO spokes are said to be three times stronger than their stainless steel counterparts, at half the weight, while providing better dampening against road shock. Spinergy utilizes the same PBO spoke technology in their motorcycle wheels, which gives you an idea of their overall fatigue resistance and strength capabilities.

The flexible PBO spokes work similarly to a standard spoke; they have an aluminum head on one end with a splined nipple on the other. The head is held in the hub flange, same as with a straight-pull spoke, while the splined nipple threads into the 44mmdeep co-molded rims, which use a carbon nose with an aluminum brake track. While we found that the aluminum brake track delivered better braking than a carbon surface, it also came with a weight penalty—the main culprit in the Stealth PBO’s 1840-gram weight. Since Spinergy manufactures their spokes and CNC-machines the hubs in their own factory in Ensenada, Mexico, they can offer some custom touches that other companies can’t: eight color choices for the PBO spokes and rim decals to really dial in your individual persona.

PERFORMANCE
Climbing
When climbing at a steady clip, the Stealth PBOs don’t feel too bad; it’s when the grade pitches up or you accelerate that they begin to feel sluggish. The nearly 2000-gram weight is the one blemish that rears its head with pace changes when gravity is against you.

Road comfort
 PBO spokes have made believers out of us; they are not a marketing gimmick or just a means to look different. The wheel’s ability to soak up resonating bumps in the road can be directly credited to the PBO spokes’ superior damping qualities in comparison to metal spokes.

Cornering feel
The PBO spokes help keep the wheels tracking through a corner by helping soak up hits that might normally throw a wheel off its line. But when really diving hard into a corner, or throwing some body English into an out-of-the saddle acceleration, there is some side to side flex that is more evident in the rear wheel.

Braking
The Stealth PBO’s well-machined aluminum brake track gave the brakes a good biting surface that was free of uneven seams, which can cause a pulsating feeling. We even got to—had to— ride them in the rain, which reminded us of why pro riders almost always choose the consistent braking of aluminum rims over carbon in wet conditions.

Windy conditions
Handling was never an issue with the 44mm-deep rims. It’s a best of both worlds depth; it gives a modest amount of aerodynamic advantage over a shallower rim, such as a Mavic Ksyrium, but not so much depth as to make it a sail for every gust of wind to catch.

Durability
Proprietary parts are sometimes something to be wary of, but the PBO spokes and hubs have been used on Spinergy wheels since the late 1990s. As a tried-and-true product, it wasn’t a surprise to us that we didn’t have any mechanical issues with the hubs, spokes or trueness of the rims.

THE VERDICT
The Stealth PBOs are able to deliver a the surprisingly comfortable ride thanks to their proprietary spoke technology. It’s technology Spinergy has been using for over a decade, but is still relevant thanks to its damping qualities. But what the ride quality can’t make up for are the hefty rims, which tip the scales past what many racers might be looking for. Even though the 44mm-deep profile provides an aero benefit, its weight-versus-depth ratio isn’t the wheel’s strong suit. The good news for the more performance-oriented among you is that Spinergy does offer a lighter carbon clincher version, the Stealth FCC, that will save approximately 300 grams over the Stealth PBO; it retails for $1940. And, yes, Spinergy offers carbon tubulars as well. As an everyday, durable and comfortable wheelset that is enjoyable to ride and has a unique look, the Stealth PBO wheels fit the bill.

Price: $1100
Weight: 1840 grams, plus 116-gram quick releases
Rim depth: 44mm
Rim width: 19mm
Spoke count: F-16/R-20
Spoke type: PBO spokes
Spoke pattern: F-radial/R-2x drive side and non-drive side
Notes: Available for Campagnolo (extra $40) and Shimano/SRAM. Includes quick releases.
For more info: Spinergy