That said, it is the engineering behind the frame geometry, fork design, an adjustable trail set-up, and overall frame stability that define the Aspero. One major goal was to provide the clearance necessary for 650b x 51mm tires, or 700c x 43mm tires with at least 4mm on either side to spare. This was accomplished in a few key ways. Up front the fork legs have a new carbon lay-up and shaping from the large 12mm thru-axle dropout on up, with an integrated crown that isn't as vertically thick as you'd expect, yet still inherently strong and gravel ready with great rounded tire clearance. Cervelo also was able to maintain a standard front-center measurement, by elongating the top tube, maintaining a road-style seattube angle, and proper trail via an adjustable front dropout design. The center of gravity is moved rearwards, as the headtube angles are more gravel/cyclocross than road. The impressive fork design and integrated headset means that the forward cockpit position feels more like a road bike- your saddle drop to bar can be more like your road fit. At the rear triangle a 420mm chainstay length was achieved with the familiar dropped chainstay design, and a seat-tube cut-out for stability and power response.

The engineers focused on the Aspero handling properly regardless of wheel and tire size, without compromising the headtube angle. The concept of fork "Trail" is best known in the mountain bike world, but is relevant across all cycling. Cervelo's Trail Mixer system allows the rider to keep effective Trail at 62mm. Larger variations in tire size effect the rearward position of the tire- affecting handling and toe-overlap clearance. By using off center, bolt-in 12mm thru-axle drop outs, the rider can select the +5 forward position or the -5 rear position of the axle. With a 700x42 gravel tire set-up, the +5mm forward is the proper position for best active handling and nimble bike control, which is what faster, race-oriented users want on more technical surfaces. If you moved it to the -5mm rearward position, it would slow the handling down, perhaps better for long, flat rides on firmer, smoother, less technical surfaces. The principles of Trail set-up come down to the outside diameter of a mounted tire and desired handling characteristics to determine your Trail Mixer set-up. This is true for 650b use, or running a lower volume 700c tire.

The use of the modified Squoval.Max tubeset is clear with the Aspero featuring a substantially larger downtube and massive bottom bracket junction over the R3. The integrated fork crown and downtube design resembles the Dropped Downtube of the aero bikes but it seems more functional for strength and visual balance from the tapered headtube through the downtube. The seattube features a squared back, cut-out design, but carries a 27.2mm round seatpost, which can provide more vertical compliance and offers more options. Everything, from the dropped, oversized chainstays, slightly curved, shaped aero seatstays, rear dropouts and Flat Mount disc interface are all stouter for increased strength. A modified Future Proof cable guide/internal routing system has an option for a cabled or hydraulic dropper seatpost, and a bolt-on downtube protector handles the debris coming off the front wheel.