How to design a super-bicycle: the story behind the S-Works McLaren Tarmac

Q&A with Duncan Bradley, Head of High Performance Design & Engineering, McLaren Applied Technologies

Earlier this week, McLaren and leading bicycle brand, Specialized, unveiled the new S-Works McLaren Tarmac. Successor to the universally acclaimed S-Works + McLaren Venge (which Mark Cavendish rode to victory in both the Tour de France and UCI Road World Championship), the new Tarmac is the most exclusive and technically advanced bike ever released. Limited to only 250 pieces worldwide, it pushes the possibilities of cycling and sets a new benchmark in complete performance.

Duncan Bradley, Head of High Performance Design & Engineering at McLaren Applied Technologies, explains the story behind the bike’s design.

Can you explain McLaren’s contribution to the S-Works McLaren Tarmac? What processes were involved in its design?

We started a study about two and half years ago where we used sensors to collect data from riders on bikes in our test labs. We then created a simulation of a bike, which meant that we could effectively design a bike virtually and make unlimited alterations to the bike to make it go faster.

The benefit of moving the design away from the road and into a simulated environment was that we could make modifications in much less time; we didn’t have to go away, build new parts and then test them. Instead, we could simulate any changes to the bike and test them virtually.

Another benefit of simulation is that it allows us to see things within the ‘system’ of the rider and a bike that are very difficult to measure out on the road, for example, how the muscles interact with the bike and the differences in weight distribution. The model has allowed us to innovate much faster, to see all of the sensitivities within the design that make up performance, and also to design components which maximise that performance.

McLaren pioneered this method of working in Formula 1, and more recently has been applying this same process to multiple other areas – high performance design being one.

Can you explain what ‘Rider-First Engineered’ technology means?

It’s a completely new approach to frame design that begins and ends with the rider.

If you take a car as an example initially, the driver is relatively insignificant in the overall mass of the car. In a bike it is very different because the rider is a large part of the overall weight of a bike. Although the bike frame might be stiff and light, generally riders – even if they are professional athletes – are wobbly masses. This has a huge effect on how you would design a bike.

In a car, you’ll have an engine to power the machine, but the rider is that engine in a bike. This means we have to think about how the rider interacts with the bike and how the bike interacts with the road, how the rider is producing power in the bike and how that makes them go faster. And then we also need to factor in that each rider is different – taller, heavier, leaner and so on. This is what we mean when we talk about ‘Rider First Engineering’ or ‘driver in the loop’ technology.

What makes the S-Works McLaren Tarmac unique, in your opinion?

We considered the rider as part of the frame design. This has been revolutionary because, unbelievably, it hasn’t been considered before. We used simulation to optimise the frame for a certain rider weight or rider size, and this has been a real step forward in the design process.

How does the design of the S-Works McLaren Tarmac differ to ‘standard’ or ‘routine’ bike design?

As far as we can tell, this is the first time that simulation has been used. The more traditional way of designing bikes, which a lot of people are still doing, is based on subjective knowledge and feedback. You’d build a bike and then listen to feedback from a test rider; similar to what went on in Formula 1 about 40 years ago!  This process can often be slow and inaccurate.

Essentially, we needed to get a handle on the engineering; to talk to the rider and know what they were going to feedback before they told us. That’s exactly what simulation allows us to do, so now we can modify a bike and expect to see a certain performance on the road. We can talk to the rider in engineering terms and understand exactly what they are saying because we have the data to back it up.

Where is the S-Works McLaren Tarmac being used in elite sport?

You’ll first see the new Tarmac in competition in the Tour de France, and then other races after that. Keep your eyes peeled!

What does bike design of the future look like?

We are already developing a much better understanding of what makes a fast, fun bike. We have a real engineering handle on that, so we know what parameters we need to change and can measure and control them to influence performance. In the immediate future, we’ll continue on this path to make bikes much better.

In the years to come, electronics will play a part. Perhaps bikes will become more adaptive and will be able to attune themselves depending how or where you’re riding. This follows a lot of other industries that are going that way, where sensors and technology are helping you to build more intelligent products.

To register your interest in purchasing the S-Works McLaren Tarmac, please visit: www.specialized.com/sworksmclaren