# PSI in your cross tires?



## bikerboy337 (Jan 28, 2004)

At this point, going to be running my CX tires (Hutchinson Pro Series, 700 x 30c) mainly for commuting... noticed that the tire says the mx PSI is 70 and min is 40.... wondeirng what people would run with these tires... used to my road (110psi) and mtn (35), but no idea what people run their cross tires at...

also, for off-road/cross rides, what would you run them at...i'll be doing a bit of that as well..

thanks for the help..


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## euro-trash (May 1, 2004)

bikerboy337 said:


> At this point, going to be running my CX tires (Hutchinson Pro Series, 700 x 30c) mainly for commuting... noticed that the tire says the mx PSI is 70 and min is 40.... wondeirng what people would run with these tires... used to my road (110psi) and mtn (35), but no idea what people run their cross tires at...
> 
> also, for off-road/cross rides, what would you run them at...i'll be doing a bit of that as well..
> 
> thanks for the help..


There is no one answer, it vaires on the terrain. You will get as many answers as there are posters on this board. Check the archives, we've gone through this several times in the past. Also, check the tech section of cyclocrossworld.com There is an article on this subject.


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## cxwrench (Nov 9, 2004)

*depends on how much you weigh...*

and how you ride. i would say conclusively 1psi over what ever pressure you would pinch flat at. just keep dropping the pressure 'til you pinch, then go 1 over. and you're gonna commute on cross tires? on pavement? go easy on the corners...


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## Gripped (Nov 27, 2002)

cxwrench said:


> and how you ride. i would say conclusively 1psi over what ever pressure you would pinch flat at. just keep dropping the pressure 'til you pinch, then go 1 over. and you're gonna commute on cross tires? on pavement? go easy on the corners...


Pressure in 'cross is alchemy. No right answer really. I like to say go as low as you can for racing. And that's going to depend on course layout, your weight, your riding style, etc.

I don't recommend commuting on 'cross tires since you will be spending $$$ to replace them all the time. Those nubs wear down fast on pavement. At least go with a semi-slick like Michelin Jets ...


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## Ronsonic (Nov 11, 2004)

Okay, so I think I've got it. Put a lot of air in the tires. Then let some out and try it, and let some more out and try it, rinse and repeat until you get a flat. Then put in a couple more pounds and you're all set.

Just like my method of tightening bolts, torque it until it strips and then back off a little.


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## atpjunkie (Mar 23, 2002)

*all by the seat of your pants*

depends on rider weight, riding style, course, etc... in a World Cup race Sven Nys was yelling tyre type and pressure to his pitcrew as he went by and they changed accordingly


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## cycloscott (Dec 16, 2002)

Commuting on pavement: 70psi 
Off-road - depends on terrain.
--lots of rocks to cause pinch-flats: 60-65
--more buff: 55-60
--soft: 50-55

Lower if you're light on your wheels. More if you're above 160lbs.


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## NoMSG (Mar 6, 2004)

*My numbers*



bikerboy337 said:


> At this point, going to be running my CX tires (Hutchinson Pro Series, 700 x 30c) mainly for commuting... noticed that the tire says the mx PSI is 70 and min is 40.... wondeirng what people would run with these tires... used to my road (110psi) and mtn (35), but no idea what people run their cross tires at...
> 
> also, for off-road/cross rides, what would you run them at...i'll be doing a bit of that as well..
> 
> thanks for the help..


I'm 160 and use my CX for a steep fireroad climbs/descents. For traction and control I run them about 40-45 psi, of just enough to keep them from pinch flatting. At first, I ran higher pressures but traction was signficantly compromised. I run 28 mm in front and 30 mm in rear (but only because that's what my used bike came with).


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## AJS (Aug 7, 2003)

All depends. On my CXer on-road I ran about 90 psi on 28c Vred Campos, my weight being 195-205 lbs.


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