The new Vielo R+1 is a road-oriented single ring only bike, designed to take advantage of the extra range and cable-free shifting offered by the new SRAM AXS wireless groupsets.
The decision to go single ring only has allowed Vielo to rethink the bottom bracket area of the bike. Usually, the need to accommodate the second chainring means that the chainstays have to be tall and thin behind the bottom bracket shell, which also needs to be narrower on the drive side.
But the R+1’s bottom bracket shell can symmetrically fill the entire area between the bearings, allowing Vielo to increase stiffness and power transfer, without reverting to a wider bottom bracket standard. The down tube can also be spread out to a wide interface to the bottom bracket shell. Vielo reckons that there’s a 32% increase in lateral stiffness over a design which will fit a two ring chainset, increasing pedalling power transfer.
The design also means that Vielo can play with the chainstay shape, making them wider and less tall, without getting in the way of the single chainring or affecting the tyre clearance. There’s ample room to fit 30mm tyres and Ian Hughes, Vielo’s founder, says that he’s fitted a slick 36mm WTB tyre in the R+1 frameset. The design also adds extra vertical flexion to the chainstays, to helps smooth the road surface.
That’s coupled to Vielo’s unique seatstay design. The big flat area at the seat post junction also helps with compliance and should improve aerodynamics.
Although Hughes doesn’t claim that the R+1 is an out-and-out aero bike, it has Kammtail profiles to the down tube, seat tube, seatstays and seatpost. There will also be the option to fit a standard round profile dropper post, using an adapter, if you want.
Gearing-wise, Vielo fits SRAM’s 12-speed 10-33 cassette and pairs it with its own chainring, which will be available in 38, 40, 42, 44 and 46 tooth options, with a second ring provided with the bike so you can alter your ratios to fit your planned rides.
Two frame options
The higher spec UD frameset has a claimed weight of 880 grams. It comes with a bespoke carbon bar-stem combo which lets Vielo route the brake hoses entirely internally into the frame, for a very clean look. There’s a planned range of bar widths between 380mm and 460mm and effective stem lengths between 80mm and 120mm.
Price will be £3999 including the bar and seatpost and Hughes says that a top spec build with SRAM Red eTap AXS and DT Swiss deep section wheels will come out at around £10,000.
Meanwhile the UDG frameset has a claimed 1100 gram weight, uses a conventional bar and stem and routes the cables externally from the bars to the frame ports in the down tube. It’s priced at £2699.
Both frames have the option to mount the down tube bottle lower, where it should be more aero, using a third bottle boss. You also get mounts for a top tube bag and a third bottle under the down tube.
Hughes expects availability of the R+1 from September, via Vielo’s dealer networks in the US and UK, along with the option in these and other markets to order online for set up and collection from a local bike shop.