The perfect bike fit – deliver more power, create less drag!
It turns out that moving air out of the way is quite hard work! This seems a strange thing to say, given that we do this every day without thinking about it. But climb on your bike and accelerate up to any kind of speed, and most of the work you’re doing is moving air out of the way. Just imagine how quick your bike split would be without air to worry about, say on the moon. Those of you thining that the surface of the moon isn’t exactly ideal for a Tri bike have clearly never ridden the Chirk Triathlon bike course. I digress.
The point I’m trying to make is that there are three ways to get quicker on the bike:
- Get stronger and fitter. This requires a lot of effort.
- Buy more aerodynamic kit. This requires a lot of money.
- Move less air out of the way. This requires neither of the above.
So how to achieve point 3? A bike fit from Chris Prior at Total Tri Training. Simples! (as a small hairy animal advertising a well known comparison website might say).
Chris is a former semi-pro cyclist and triathlete and draws on all of this experience when it comes to fitting bikes. He explains that a triathlon bike fit needs to be different from that of a regular cyclist. Cyclists have the luxury of completing their ride and collapsing in a broken sweaty heap. After finishing their ride, the average time-trial rider is lucky if they are able to walk to the local village hall for a cup of tea with an old bearded bloke who remembers “when Chris Boardman rode this course.” The average triathlete is by this stage well into their run and starting to wonder what the hell they were thinking. Oh to be discussing Boardman over a cup of tea.
The bike fit starts with Chris explaining some of the basic principles of the fit. He shows photos of both the positions of some the pros and previous bike fits he has done. He demonstrates some of the differences between the positions of time-trialists and the pro triathletes, and shows photos of athletes in wind tunnels. But he points out it’s not all aerodynamics. Whatever position you are in you have to be able to sustain the power, and sustain the position. I’ve never been into yoga, but even I could probably fold myself into a position with my chin on the front wheel (downward dog??), but I’m not going to be able to pedal very well and I certainly can’t stay there for very long.
Brief over, I get kitted up and get on the bike. Now I have a habit of tweaking my position a lot, often with the help of a large mirror. Honestly, it’s not vanity. I can’t really imagine anyone looking worse than after a hard turbo session. Not many relationships started in a spin class. But I’m hopeful that all these tweaks may have paid off. In my head I already look like Bradley Wiggins….
Chris takes a baseline photo and brings it up on the screen for me to see.
Chris: This is you at the moment.
Me: Ah yes. The “Meerkat wearing a pointy helmet look.”
Chris: Mmm. You could be a bit flatter. You’re quite far back. And your saddle is very high.
Me (quietly): Dammit.
Chris uses his software to measure the various angles from the picture he takes in each position (see below). He looks to optimise these as the fit goes on. The first thing to sort is the saddle. Chris explains that with it very high I’m putting a lot of tension on my hamstrings which I’ll be needing for the run. It is also costing me power as I can’t pull through the bottom of the pedal stroke properly. He lowers it in tiny steps until he’s happy, then measures the knee angle to check. Next up is the saddle position. Again he brings it forward in small steps, monitoring my hip angle. At each stage Chris checks my pedalling and feel in terms of power.
Then we move onto the front end. Chris explains this is key as it determines the position of my back as well as the front silhouette I present to the air. Chris takes me forward and down, and in so doing minimises any change in my hip angle further back. The elbows come in a bit. Each change is again made a small step at a time with comfort and pedalling checked.
The next stage is to look at helmets. I have my shiny new Rudy Project Helmet with me but brought my old Giro Helmet along too for comparison. The Giro cost me £40 from eBay several years ago. I won’t say how much the Rudy Project cost in case my wife reads this! As I climb onto the bike in the Giro Helmet Chris starts laughing. He doesn’t need to say any more. Anybody want a Rudy Project pointy helmet?
Having adjusted the front end there is a slight adjustment to the saddle and the final position is sorted. As a final test Chris cranks up the resistance on the turbo to check I can put out the power in the new position. The final picture looks a little different, and it certainly looks like I’ll be moving less air out of the way from now on!
Huge thanks to Chris for the fit and his ongoing mechanical support and advice.
To book at fit contact him at: firstname.lastname@example.org.
Or via the website: www.totaltritraining.com/bike-servicing-and-maintenance/