FAT OR T HIN?
When it comes to tyres, how wide should you go?
Burt spent 12 years as head of physio at British Cycling and five years as consultant physio at Team Ineos. philburtinnovation.co.uk
“I’ve looked after sprinters who couldn’t ride to the velodrome due to their crippling back pain...”
My clients will often ask me, ‘What’s the easiest way to make my bike, or ride, more comfortable?’. After much consideration, I’d have to say that for most road-bike users the way to most easily achieve greater comfort on your rides would be to increase your tyre width.
It’s a belief that has been confirmed to me in many different ways over the years working as a physiotherapist. During my time at British Cycling, as well as at Team Sky, if a rider had a lower-back injury we would automatically widen the tyres they were using from, say, 18mm to 23mm – if the frame would allow, of course. I’ve looked after sprinters who couldn’t ride to the velodrome due to their crippling back pain who could subsequently cope with two-hour recovery rides on the back of the change of tyre width alone.
These days, I often see clients with debilitating aliments, such as lower-back pain, who turn away from road cycling and start riding mountain bikes to try and resolve their back issues. I used to think this was due to the more relaxed, upright position. However, I now believe that the fat, cushion-like tyres have as much, if not more, to do with the rider’s increased comfort.
Increasingly, and particularly with the rapid rise of the popularity of gravel bikes, more and more people are finding that they prefer the added comfort that innovations, such as Specialized’s Future Shock (see p34) technology, deliver.
Many also prefer gravel bikes when riding on the roads – but why? Suspension has for a long time been engineered into mountain bikes but we’ve seen it on road bikes too, either through the lay-up of carbon, strategically placed elastomers or via seatpost suspension. Equally the massive increase in tyre widths can now be easily accommodated within what is essentially a road-frame geometry.
In road bikes the aim has always been to improve comfort by trying to absorb some of the forces the road throws up to the rider vertically: the bumps and shudders. However, the increased air cushion (and therefore volume) a wider tyre provides is hard to beat in terms of achieving this goal. First of all, it’s close to the point at which the force is generated and therefore much better at dissipating it – once a pothole has shuddered into your frame it’s harder to deal with.
Cycling is predominantly carried out in a lowerback flexed position. This is generally a more ‘open’ joint position and is therefore slightly more vulnerable to injury. While it’s not as risky as lifting a huge weight with a flexed spine and, of course it is supported as we are sitting, that seat can nevertheless transfer a significant amount of vibration into the pelvis and lower back.
I would also add at this point that I don’t think anyone riding 23mm-thin, race-hard tyres has to change if they don’t have an issue. I would argue that a switch to riding with a wider tyre helps to alleviate the problems that we are taking onto the bike; issues that need accommodating, rather than ones that are caused directly by riding with a thin tyre.
But, of course, wider tyres have a down side too. Suspension anywhere in a frame or seatpost basically means extra weight. While it used to be believed that wider tyres meant more rolling resistance, and thus more force to overcome, slowing you down this has been disproved. And, with the advent of higher, deeper rims that cup the wider tyres you can benefit from a more effective rolling surface to go quickly with.
Ultimately, it comes back to a goal-centred approach. If you’re a racer and you need to win then it may have to be 23mm and 100-plus PSI and put up with the back pain. But if your goal is to ride longer with more comfort then tyre width could be the easiest way to achieve an armchair ride.