Call us old-fashioned but we love the way a CNC milling machine works its way through a block of aluminium at 15,000 rpm, leaving a flat surface that mirrors your reflection. We put Fulcrum’s elaborately manufactured Rapid Red 3 650B aluminium wheels to the test and tell you how they perform.
The future belongs to carbon – you can be sure of that fact when it comes to chasing seconds in the pro peloton but as hobbyists, occasionally we want to take the time to enjoy the ride and take in our surroundings. In anticipation of that kind of experience, we fitted one of our test bikes with the Fulcrum Rapid Red 3 650B aluminium wheels. Aluminium may seem like an outdated material to some but the technology in these wheels is state-of-the-art. We’ve got all the details here.
The 6082 aluminium alloy of the rim has been subjected to a pre-ageing heat treatment to improve its mechanical properties. To save weight, excess material between the spoke holes has been machined away, bringing the weight of the wheels down to 1,640 grams. In addition to a marginal weight saving, this makes the finish of the wheels look particularly high-tech. The rim has also been machined around the valve bore, allowing the included tubeless valves to sit flush with the rim and create a lasting seal. You won’t really notice the inconspicuous black decals in daylight but they reflect approaching headlights when it gets dark for added visibility.
To compensate for the imbalance caused by the weld seam in the rim, Fulcrum use spokes with a slightly thicker diameter on the opposite side of the wheel, dubbing this approach Rim Dynamic Balance (RDB). The wheels are built up with 24 straight-pull spokes in a 2:1 ratio, with 8 spokes keeping the wheel in shape on the low-tension side and 16 spokes on the high-tension side of the wheel i.e. the disc rotor side up front and drives side at the rear. Fulcrum claim this results in less distortion of the wheel, more efficient power transmission and that this lacing pattern makes for more balanced spoke tension, reducing fatigue of the system. The wheels use cup and cone bearings with a preload adjuster to take out axial play. This is set up once the wheels have been installed in the frame. The maximum permissible weight of the Fulcrum Rapid Red 3 650B wheelset is 120 kg, which includes the weight of the bike, the rider and their luggage.
The wheels come 2Way-Fit ready. This is Fulcrum’s designation for rims that are compatible with both tubeless and tubed clincher tires. Fitting tubeless tires is easy with the supplied valves and the pre-installed rim tape. Our test tires happily and loudly popped onto the rim on our first attempt at inflating them. The Rapid Red 3 650B wheelset is only compatible with CENTER LOCK disc. This requires an external bottom bracket tool to tighten the lockring to 40 Nm, so you may have to visit your local bike shop if you don’t have one handy.
With a 29 mm outer rim width and 24 mm internal width, the rims are on the modern and wider side of the current gravel spectrum. The rim depth is a shallow 24 mm. According to Fulcrum, the wheels work best with 40–60 mm wide tires. On our test bike, our Vittoria Terreno DRY 47C tires, which already had some miles on them, inflated to a width of 50 mm at a pressure of 3 bar. We wouldn’t fit wider tires than that. If you want to go even wider, you’ll have to accept compromises in the tires’ cornering stability due to the lack of lateral support. An inner rim width of at least 27 mm would be better suited in that case.
Fulcrum designed the Rapid Red 3 650B for riding on varied terrain and that’s where we tested them. In addition to asphalt and gravel roads, we didn’t spare the Fulcrum Rapid Red 3 650B wheels the occasional excursion onto moderate singletrack. Due to their aluminium construction and the added grams on the scales, the Rapid Red 3 aren’t the fastest gravel wheels on the market. Long climbs require a little bit more effort but you’ll still get up them easily enough. What additional fatigue you have to accept in your legs, you gain back twofold in your arms. Besides being as tough as a seasoned boxer, the wheels also offer good damping characteristics. They noticeably absorb smaller impacts and vibrations instead of passing them on to your arms. The rims happily shrug off hard impacts on rough terrain. As such, the wheels turned out to be ideal for short micro-adventures around our head office in the Stuttgart area left us confident enough to use them on longer multi-day rides.
If you still aren’t convinced of the quality of the Fulcrum Rapid Red 3 650B wheels, each set comes with an identification card. This certifies that your wheels were subjected to a rigorous battery of tests before they left the factory and found their way onto your bike. If worst comes to worst, this also enables Fulcrum to retrace every step of the wheels’ manufacture and their individual components. The almost completely silent freewheel left a lasting impression. Let your gravel bike roll, relax and hear the gravel crunching under your tires. You immediately feel at one with your environment, able to let go of your worries. In addition to the Rapid Red 3 650B, Fulcrum’s Rapid Red 3 range also includes a 30 mm wide version for 700C tires at the same price. Both wheelsets are exclusively compatible with 12 x 100 mm front and 12 x 142 mm thru-axles. The Fulcrum Rapid Red 3 650B wheelset is available with an HG/Campa freewheel for € 605 or an XD freewheel for € 613, which we think is fairly priced.
The Fulcrum Rapid Red 3 650B wheelset offers a relaxed gravel experience at a competitive price. The elaborately machined aluminium rims make some of its carbon competitors look boring. With their damping properties and durable construction, the Rapid Red 3 650B wheels make sense for gravel bikes with lots of tire clearance.
- good damping qualities
- high-tech finish
- good value for money
- 24 mm internal rim width is too narrow for tires up to 60 mm wide
- comparatively heavy and therefore a bit slow in acceleration
Price: € 605 (CENTER LOCK, 12 x 100, 12 x 142, HG)
Weight: 1,640 g (including tape/valves, with HG freewheel)
Duration: 1 month
More information: fulcrumwheels.com
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Words & Photos: Rudolf Fischer