At Sea Otter this year, ENVE introduced a 650B rim, which they are calling the Twenty7.5 (650B), and they’ll come in an AM and XC version. The Twenty7.5 rims are 31mm wide (24mm internal) and weigh in at 410 grams for the AM, and 24mm wide (18mm Internal) and 360 grams for the XC, and will retail for an $875 each. They will also be available as built wheelsets, using the DT Swiss 240, DT Swiss 180 and Chris King ISO hubs. Like all their rims, the clinchers use 100% uni-direction carbon fiber construction, and use their molded spoke hole technology, and are hand built in their Utah plant.
ENVE Twenty7.5 AM
This is going to be a different review, since although I am testing a wheelset; I am primarily focusing on the ENVE rims themselves. The wheelset I tested are comprised of the ENVE Twenty7.5 AM carbon rims (32 hole), laced to Chris King ISO hubs (15mm front and 12x142mm rear) using DT Swiss Aerolite spokes, and they retail for $2550. The basic dimensions of the rims are an outer width of 31mm and an inner of 25mm, and a height of 30mm, and they are available in 28 and 32 hole configurations. The prebuilt wheels weighed in at 1701 grams, and I’ll have to use their specs of 410 grams for rim weight, since I was unable to measure them myself. For an All Mountain rim, weighing in at 410 grams is pretty amazing, and the big chunk of weight for the wheels was the moderately heavy Chris King hubs. For a lighter build, using DT Swiss 240 or 180 hubs can drop 110g and 180g respectively from their heft. You can purchase the rims separately for $875 for your own custom build. The rims have a 5-year defect warranty for materials and workmanship, and a Lifetime Crash Replacement policy, in which the replacement would be 50% off MSRP.
The ENVE rims are handmade at their facility in Utah, and the rims have gone through extensive and rigorous torture, including lateral stiffness and spoke testing, and meet the strenuous UCI test protocol. They have a molding process for the spoke and valve holes, so that the carbon fibers are continuous and unbroken around the holes, which creates maximum strength and allows increased spoke hole tensions. In addition, they mold in a conical nipple seat, which reduces spoke breakage and allows nipple articulation. In another innovative design, they use removable bladders, leaving no excess internal material, so they have a lighter end product and one that make for easier wheel builds. The unidirectional carbon rims are unpainted, without any coating or finish, and are raw and naked, other than a few decals.
Testing Rig and Terrain
Testing was performed on my medium Ibis Mojo HD with the Cane Creek Double Barrel Air rear shock, Magura TS8 27.5 fork, and Schwalbe Nobby Nic tires. I am 5’9″, weigh in at 155 lbs and have been riding since the inception of the RockShox RS-1, and started out on a Bridgestone MB-2 for my first MTB steed. I have mostly ridden in the West, including vast portions of the Colorado Front Range, Sedona, Moab, Fruita/GJ and many parts of the Colorado mountains. The testing terrain is predominantly loose rocky conditions, with many long steep climbs and descents, rock gardens, slick rock, an occasional smooth singletrack and lots of ugly loose gravel.