Tyre pressure cyclocross on gravel

[Duke Caboom]

I race in off road duathlon competitions on my cyclocross bike (33mm slightly knobbly tyres) on mostly fairly tightly packed gravel or dirt. I've done them before and run hybrid-type pressures. Around 80psi cos higher's faster, right?

The course is usually basically 4 sides of a square, so cornering isn't an issue. However, this weekend is a different course, with some wiggly bits. I don't think there will be slippery climbs or slow tight turns, though, like an actual cyclocross.

I've also seen people suggest 33psi for cyclcross but I think this is for traction, which isn't usually a problem on this course. I've also seen people with proper gravel bikes and gravel bike tyres going wider and lower pressures, apparently for speed.

I don't really follow cycling so feel free to shoot me down.

What pressure would you go for for speed? Thanks

[gazza285]

I run as low as 25psi when racing ‘cross, but you’ll knacker your rims riding that pressure on gravel.

How wide are your tyres? Running ‘cross tyres at that pressure will not be comfortable, I’d go for the widest tyres you can fit in the frame and go for a lower pressure.

[Bilkob]

80psi? Off road?? Have you got any teeth left….?!
I tend to run up to 50psi off road if it’s really dry and un-gnarly, drop it down to 30-40 if it’s a bit technical or slippy

[frisbee]

Mathieu van der Poel just won the fastest ever Paris Roubaix on 32mm tyres at 52 psi.

[lufbramatt]

How heavy are you? This will affect how low you can go.

I'd drop them down to 45psi and see how you get on.

[Siao]

Silly question, is it tubed or tubeless? I can't make my tubeless keep more than 50psi. It very quickly drops to 40ish.

[irc]

I would say 80psi is almost certainly too high. Any benefit from very high pressures is only on very smooth roads.

As above it depends on your weight and usually the f o t tyre should be lower as it carries less weight.

This article gives a good starting point for various tyre widths and wheel loads. IE combined weight of bike and rider split between both wheels. Maybe 60% rear 40% front.

https://www.renehersecycles.com/tire-pressure-take...

[Duke Caboom]

I went with 50psi and it seemed great! Felt significantly faster on gravel and there was a much-bumpier-than-usual bit which would have been unbearable at 80! So all good. Will now try to hone it, maybe down a bit more. And look at variation front to rear.

Thanks for all the advice.

[Siao]

Duke Caboom said:

I went with 50psi and it seemed great! Felt significantly faster on gravel and there was a much-bumpier-than-usual bit which would have been unbearable at 80! So all good. Will now try to hone it, maybe down a bit more. And look at variation front to rear.

Thanks for all the advice.

Good to hear!