The new Ribble Ultra SL is an outrageously aerodynamic bike that drew significant attention on the first day of the Rouleur Live show. Designed in the UK, the bike's integrated approach to smoothing its passage through the air sees bike and rider considered as a single entity.
The bike’s profile is almost fairing-like in the way it mitigates the transition between machine and rider, a feature which is very noticeable on areas like the radically shaped cockpit and truncated downtube.
Ribble has spent significant sums of time and money verifying its work in the wind tunnel. It's aim is to give the rider the feeling of slotting in behind the bike, and this has been used to good effect by the Drops-Le Col and Ribble-Weldtite teams.
The SL R has become the flagship model in a highly revised range of bikes that aims to turn Ribble from a company predominantly known for discount bikes into one of Britain’s most innovative brands. We caught up with CEO Andy Smallwood to find out more about Ribble's unique approach to unified design.
“Over the past four years, Ribble has gone back to its roots as a premium British bike brand,” says Smallwood. “Everything is designed and assembled in the UK. We’ve invested heavily in R&D and brought onboard former racer and designer Jamie Burrow who’s been instrumental in creating our range.
"It’s been a four-year process where we’ve really focused on the product. Everything we make is now designed by us and manufactured exclusively for us. Each bike is then assembled with one mechanic to each bike in Preston.
"We’ve worked across the entire range. It’s been a significant project. In 2019 we launched 23 new models. This covered road, gravel, urban and electric bikes. Two years ago we also launched the world’s lightest electric road bike. We had that title about a year ago, but our latest design has won it back again by coming in at about 10.5kg.
"We always try to look at things differently from the competition. The Ultra SL is a good example. The brief was to make the world’s most aerodynamic road bike. To do that, we had to look under the skin of what really makes a bike aerodynamic. The critical thing is not to just focus on the bike, but the bike and rider together.
"From the ground up, the Ultra SL is designed to consider both. Early in its design, we worked on a very aerodynamic handlebar. We saw a significant gain, but once we put a rider on it and got into the wind tunnel, a big chunk of the improvement was lost as the air hit the rider.
Like riding behind a van
"We started looking at why the air was hitting the rider and how we could reduce the effect. We call the solution we came up with ‘wakes generators’. On the handlebar, you can see these bulges with a truncated aerofoil shape. They create a space for the rider’s legs to sit in.
"A very flat handlebar may be more aerodynamic by itself, this design working in combination with the rider is actually much more efficient. Essentially we’re creating a hole or wake in the air for the rider. If you imagine riding behind an aerodynamic sports car or a van, being behind the van will provide a larger wake. It’s why we don’t just consider the bike’s profile, but the benefit that being behind it passes on to the rider."
Direct mount efficiency
"Another change we’ve made is the direct mount brake levers. We wanted the handlebar to work in harmony with the rider. But bars are conventionally round. This is purely so they can accommodate the lever clamp. We thought there’s an improvement to be made here.
"By creating a bar that can directly accommodate the levers, we were able to create both a more aerodynamic shape and also improve aerodynamics. The bars themselves are also narrow when measured across the hoods to promote a more aerodynamic position.
"A similar approach applies to the profile of the downtube. It’s explicitly designed to work best with a water bottle. It’s actually more efficient with one in place.
"Like all our bikes, the design process for the Ultra SL started with an initial concept. Then we create the shape digitally. There’s a significant amount of computational fluid dynamics (CFD) to hone the design. Then we’ll create a rapid prototype. From there, we’ll make a viable sample. That gets used to verify the CFD data in the wind tunnel. Then we’ll look at real-world testing to ensure the feel of the bike is correct too.
"We’ve now got two teams that also provide input. The women’s Drops-Le Col squad and the men’s Ribble-Weldtite Continental team. Seeing our bikes at the Women’s Tour and Paris-Roubaix has been amazing. Their feedback and our approach to aerodynamic design is something we aim to use across the range.
"Another thing that sets us apart from much of the competition is our custom build option. You can have exactly the spec you want. You spend a lot of money on a bike, so it’s good to have a choice when it comes to groupsets, tyres, stem length, crank length. We want each bike to work perfectly for each rider”.