Part Four: Aerodynamics, Rolling Resistance And Drivetrain Friction
Phil Jones
“Rebecca, kit wise. Did you go with normal bib shorts and top, or did you go with your skin suit?”
Rebecca Richardson
“Skin suit. There are massive aerodynamic advantages. Anyone wanting to make an attempt, they just need to look at the aerodynamics and how they can best improve their chances of that [high] average speed. That’s what it’s all about.
“I had a road bike, but I spent a good…Again, we talk about that research aspect, Phil. I listened to all the aero/TT podcasts: there’s a time-trial podcast and obviously one from the
RRA. I was asking people who are real aero geeks: what do I do?
“Aerocoach has information available on their website about bottles. I had a bottle on my seat steam because that’s the most aerodynamic position, and that research is out there. I had some ‘trip’ socks with Velotoze shoe covers. Apparently, that’s a very fast combination. The Velotech suit I had has been tested and has done really well in tests, so I felt pretty happy with my Brother skin suit.
“I decided to go pure road in the end. I did also buy some clip-on bars and practised with them, but in the end I decided to take a different slant with the road bike and ended up going with a standard set-up. I bought an S-Works Evade helmet, which is one of the fastest out there, so, yeah, I did a bit of research.”
Timothy John
“The tyres you were using, Rebecca…You know, I often think that the tyres are the most overlooked component of a bicycle. It’s literally the only point of contact between you and the road, and you had some very fast tyres for this attempt.”
Rebecca Richardson
“Yeah, rolling resistance of a tyre on the road is a massive factor, as are dry or wet roads. I even read that a moist road, a damp road, can be faster than a dry road. I was having all of these conflicting amounts of research that I was listening to, in terms of what do I do and when do I go. I decided I wanted dry roads for cornering. The tyres I had were [Vittoria] Corsa Speeds. I think the tubeless 25mm Corsa Speeds have been tested as one of the fastest in the world, which is why I chose to use them on the day.
“When I typed in the rolling resistance of that particular tyre at the pressure I wanted to ride at into the algorithm on My Windsock which is a piece of software where you can analyse how fast you might expect go at a given power output, weather conditions and kit and position, the rolling resistance of the tyre seemed to play a massive part in changing that outcome,
so I made sure to have it on the day.”
Timothy John
“Did you practice with any of your race day set-up, or did you keep everything in reserve in the hope of a psychological boost if nothing else?”
Rebecca Richardson
“I practiced with the wheels that my friend leant me. It was a bit of beg and borrow situation. She had a lovely set of HED wheels. I wanted to proactive with those. She also had a disc wheel, so I practised with that. I practised with a clip-on handlebars versus being in the drops. The only thing I didn’t have was a full skin suit, so I was hoping that would give me a slight mental boost on the day.”
Phil Jones
“Rebecca, dare I ask about your power output? Can you recall what your peak was, your average was, your normalised was? Just for the geeky listeners out there who like to hear such things.”
Rebecca Richardson
“Yeah, my normalised was 197w. I changed power meter the day before. I ended up using a Dura-Ace crank power meter, where normally I use the PowerTap pedals. Based on the performance I put in and the average speed, it would suggest that maybe they were slightly under-reading, but let’s just say I think that was a good enough round figure there. I think max output as about 300w. I never really went very hard on the ride at any point.
Phil Jones
“That’s all about power to weight ratio there, isn’t it? If I was pushing 197w, Rebecca, I’d end up going about 17mph average on a flat road. How trained you are, your weight and I guess all of your hill climbing experience, really came to the fore on that type of circuit. That hilly circuit leant itself very well to your riding style and physique, I guess.
“So does that mean that in future you’ll be looking to target other RRA records with similar profiles across the country? Are we going to see as great a success for you with RRA records as we’ve seen in hill climbing?”
Rebecca Richardson
“That would be nice!
LAUGHS
“I can tell you the news, Phil, that I’ve bought back my old time-trial bike.”
Phil Jones
“Ooh! Ok! So things are getting serious again. Right, ok!”
“So what is your time-trial bike? Tell us quickly about that.”
Rebecca Richardson
“It’s a really old, Giant Trinity TT bike, and it’s the same frame that Jonathan Schubert used to record the fastest ‘100’. When I found out that, I thought: ‘Oh, I really wish I hadn’t sold that time-trial bike!’
“I sold it to a friend of mine and he decided that he is not going to be racing for the foreseeable future. He’s got a bit of an injury. He literally told me a week ago that he was going to sell this bike, and I thought: ‘No! I can’t let it go!’ We just can’t get bikes at the moment. It’s a bit weird, but I’m buying it back off him.”
Phil Jones
“That’s a great omen, isn’t it, that the universe has brought that back to you. That can only be a good thing. So what’s the set up on it? Does it have a disc wheel? What sort of group are you running on it?”
Rebecca Richardson
“It’s got a disc wheel and a 50mm front wheel. It’s a pretty fast bike. I think the fastest ’25’ I did on it was a 53.53, so it can shift. I’m going to make some improvements to it though.
“I definitely want to play around with the body position. I always felt there was a bit too much gap between my hands and my face, so I want to get some more upright bars. Groupset-
wise, I think it’s a combination of Ultegra and 105, but I’m going to change all that.
“I’d hate to admit it, but it’s going to be faster. I kind of say that because you don’t want to have to buy a TT bike, because you think, ‘Does it really give me speed?’ But all of that drag is coming from your body, and if you can get your body down and stay in that position…And then the components. Having things like hidden brake calipers really does help.
“So, in answer to your question, I might go for some more [records].”
Phil Jones
“There are low cost watts you can acquire and then there are high cost watts. When you look at that scene, you can go down a rabbit hole in terms of how far you go, because ultimately it’s only really as big as your wallet and as big as your budget. Some people are investing tens of thousands [of pounds] in their entire set-up, from skin suit right the way through to the CDA of the bike right. Wind tunnel testing and all these sorts of things.
“But I think you have all the raw ingredients, effectively. Once you’ve got the physical capability, then get the technical capability and tweak that as much as you can. At a certain point,
when those two marry together, it will make a fairly formidable set-up for some of those RRA records moving forwards.”
Rebecca Richardson
“We had a waxed chain to improve the efficiency. We didn’t have bar tape. We just had electrical tape to try and wrap everything really tightly. They were the main things. We were just trying to make it really efficient, mechanically.
“Like I said, I did all that research. You can save a watt here, or save a few watts here, and that can be a lot, particularly in your drivetrain efficiency. Moving into the future, I’d always
focus a lot more on that: where can I make those ‘easy’ watts? Save those watts. I say without getting too geeky, but it is all about getting geeky, isn’t it?
LAUGHS
Timothy John
“The savings in the drivetrain are unbelievable. I did a lot of work for Muc-Off last year, and they have PhD-qualified scientists who work in a field called tribology: the science of friction. All of them said the sheer complexity of the bicycle chain leaves everything else for dead, really,. It moves in different directions at the same time. Part of it is slack while part of it is under tension. Part of is fixed, within the link, while the other part is revolving .There are so many different factors to take into consideration before you begin to formulate the lube.
“So huge amounts to be gained there, and, of course, they worked with Brad Wiggins when he broke the Hour Record back in 2015. They made pretty much a silent chain which played a significant part.
“More prosaically, let’s talk about the RRA: proper, grassroots cycling and that, of course, is Brother’s calling card in the sport: the company and Phil, through the sponsorships, they really try and give back really trying to create platforms to perform that support the sport at the grassroots. And it doesn’t come much more grassroots than the RRA, so tell us a bit about them.”