The Wyman Method of setting proper cyclocross race tire pressure – Part 1

courtesy Helen Wyman

This coming weekend marks many of the individual countries’ Cyclocross National Championships as the international race calendar winds down to the remaining two World Cups and then the World Championships in Luxembourg at the end of January. If you’ve made it this far in the season (competing at Nats) you’ve probably already dialed in your tires. But for the remainder of us who will be watching from the sidelines (or at home) we thought we’d reach back to a discussion we had with 9-time British Champion Helen Wyman about how she ensures she has the right tires and pressure dialed for race day…

Wyman’s Tire Pressure Rule of Thumb

Unfortunately Helen is out of the this year’s race with a still healing collar bone (which she got in the European championships), but she had plenty to share when we caught up with her earlier in 2016. We’ll start off with tire pressure as we generally see amateur riders and racers who aren’t really taking full advantage of the extra grip you get from low pressures. Sure running tubulars will let you go the lowest, but a well-fitting tubeless tire can be run quite low and even with tubes you can go surprisingly soft once you know your course (and with the added pinch resistance of latex tubes.)

We got these pressure tips from her tire sponsor Challenge and her husband/mechanic Stefan Wyman who helps dial her tires in to compete.

“Helen carries out many cross clinics in a season and has a ‘rule of thumb’ on pressures. It’s her guide, and of course every rider should try things for themselves. Even though it’s not going to work for everyone it’s a way to get a starting pressure. From there you need to go up in 1psi increments (if you are hitting the rim or folding the tubular) or down (if you’re slipping in corners or hopping over the surface) in 1psi increments.”

The idea is simple; start from a low pressure, then go out and take an easy paced lap on the course you are going to be racing on, or just on a familiar track if you are doing it for the first time. It is OK with a tubular or even tubeless setup to feel the rim gently bottom out once or twice in a lap, as long as you don’t feel like the tire is about to roll off the rim in hard corners or off camber sections. Even with tubes, it is best to try and work down to the point where you are almost bottoming out on the rim once per lap (that’s why this guide starts low), and then you can add more pressure to get back up and away from pinch flat territory. If you are more comfortable not hitting the rim at all, bring the pressure back up 1psi at a time until you can complete a fast lap without feeling the rim. Our advice is also to start with 2psi more in your back tire, as cyclists tend to put more of their weight over the back wheel and have better luck with lifting the front over obstacles.

SKS-Airchecker_digital-pocket-tire-pressure-gauge_cyclocross_1-75bar_25-5psi

Of course you are going to need more than the gauge on your pump to get those small increments. We recommend starting with a floor pump with a low pressure dial, maybe even something like the SKS Twentyniner that we tested last year. Then you can roll around the course during practice with a small handheld gauge and a pump in your pocket. We use the SKS Airchecker a lot as it is quick and easy to use, plus whatever mini-pump happens to be lying around.

The end result is the lower you can comfortably run your tire pressure (while not having the tire roll sideways or off the rim) the more grip you will have in most conditions. Wyman’s ‘rule of thumb’ starting point for picking your tire pressure is:

For tubular tires: (Weight in Lbs / 10) + 5 = Starting point (Tubular)
So for a 150lb rider: 150/10 = 15. Plus 5 = 20. Start at 20, go up and down from there. For a 180lb rider you would start at 23psi
For supple tubeless or clincher tires with latex tubes: (Weight in Lbs / 10) + 10 = Starting point (Handmade Clincher)
So for a 150lb rider: 150/10 = 15. Plus 10 = 25. Start at 25, go up and down from there. For a 180lb rider you would start at 28psi

Those are pretty low numbers. We personally tend to race at about 4-5psi higher than that on tubulars, as it depends on each rider’s technical skill and riding style. But it is important to find the lower limits before you can appreciate what the added grip will do for your ability to rail though muddy off-camber corners, power through deep sand, or is the case this time of year safely navigate snowy & icy turns.

Join us tomorrow as we dive into Part 2 and The Wyman Method for tire selection so you’ll be sure to be racing your local cross courses on the best tread possible for the track and weather conditions…

Our thanks to Helen, follow her over at HelenWyman.com

Comments

16 thoughts on “The Wyman Method of setting proper cyclocross race tire pressure – Part 1

  1. I fail to understand why you should need a gauge especially when everything is based on feeling and number of times you bottom out. I do more or less the opposite, starting with a pressure a bit too high and releasing air incrementaly until I bottom out or feel the tires folding way too much then I readjust by 1 or 2 pump strokes. Even if I did it by starting low I wouldn’t need a gauge for that. Sounds like wasted time.

    1. Because science. So you can have a reference.

      I’d also recommend setting tire pressure at the ambient temp. 15 psi at 70°is going to be much less at 30° due to ideal gas law.

      1. Having a reference doesn’t serve much the amateur rider as the ideal pressure varies a lot depending on temperature, type of course, humidity level. The gauge of your floor pump is enough to inflate to a common baseline. Unless your coming to the races with a camper, 3 bikes and many wheelsets with tubulars from the same manufacturer this is hardly relevant

        1. If you have even two sets of wheels, or are contemplating switching tires overnight between a Saturday and Sunday race, then a numeric reference is useful.

          Pros have several and will pit during practice to change wheels/tires, searching for the right combination as close to race time/conditions as possible. When they discover a pressure that’s working, the mechanic can then set all of that racer’s tires to that pressure so it’s consistent for tire testing. Further pressure adjustment can be made from there.

          For us weekend hacks, just knowing your baseline pressure is useful so you don’t go out there too far off the mark.

  2. Tomi, no professional is showing up to a race without a gauge and a personal psi chart for each team member. (deleted)

    1. That chart is useful because they are using a sh*tloads of wheels with different threads so the mechanic can inflate them all at the very same pressure, release or add some air based on directions given by the rider during the race.

      Are you a pro rider with 2 mechanics ready to dial the pressure every lap to your recommendations ?

  3. I was reducing pressure until I only occasionally bottomed out the rim (tubeless setup), then found I was getting dirt jammed in the between the tire bead and the rim hook which caused a slow pressure leak. Depending on how hard you corner you may want a bit more pressure than 1psi over bottoming out.

  4. Seriously? Do you people ever engage before commenting?

    A professional rider explains her, repeatable, proven method for reliably getting the best performance in any given situation.

    You know, someone with many, many years of experience, both personally racing and advising all levels of riders at clinics.

    A multiple national champion, who gets paid to do what she does, because she knows her sh..
    That person. offering advice and experience to you, for free.

    And all most folk who reply can be bothered to do is complain and say how ‘their method’ is better?

    You need to take yourselves off to the quiet corner and have a little think about it.

    1. You clearly haven’t read the comments. I don’t question Wyman’s method. I question the relevance of overthinking the pressure management and applying that method as an amateur racer with completely different racing parameters (number of bikes, number of wheelsets, number of different tires available).

      Besides with all due respect to as great an athlete as Helen Wyman she is hardly a reference when it comes to railing the corners fast and staying upright on a cross bike. Many amateurs racers have as good or better riding skills than her. This is her weak point compared to other top level women cross riders.

  5. In any area of life,there are those who have worked hard at something ,studied it,got a degree at it,then gone out and proved that what they say works.and then everyone knows better than them

  6. My 0.02: Much safer for amateurs showing up on race day without multiple wheelsets to pre-ride a tad firm and veeeery carefully reduce pressure as you may dare if it turns out the course doesn’t have hard knocks. Last thing I want is to be fussing with a problem 40 minutes before my start. Typically wetter means you can get away with lower pressure, drier means faster and hitting whatever bumps might be out there harder. Too soft and you’ll be running to the pit no matter your tube-ular-less setup.

    1. @Travis, that’s pretty much a direct result of the UCI setting a max width of 33mm for competition tires. Every tire discussed and pictured here and in Part 2 is a 33mm.

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