# Pressure for CX tires?



## scottma (May 18, 2012)

This should be an easy one. I nomally ride road bikes with 25C tires and have that down pretty well. I recently built up a Surly Crosscheck for an all purpose Winter/gravel-dirt road whatever kind of bike. I wont be (I dont think so) doing any CX racing with this. Just a fun bike. I have Specialized Trigger Pro 33C tires on Mavic Kysrium Elite rims. I weigh ~ 165#. 

What would be good pressure range for hardpack dirt/gravel? Asphalt? The tires arent really meant for loose mud but if I were to ride in softer stuff, how low should I go? How low can you go on this type of clincher setup before worrying about pinch flats?

Thanks


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## cxwrench (Nov 9, 2004)

scottma said:


> This should be an easy one. I nomally ride road bikes with 25C tires and have that down pretty well. I recently built up a Surly Crosscheck for an all purpose Winter/gravel-dirt road whatever kind of bike. I wont be (I dont think so) doing any CX racing with this. Just a fun bike. I have Specialized Trigger Pro 33C tires on Mavic Kysrium Elite rims. I weigh ~ 165#.
> 
> What would be good pressure range for hardpack dirt/gravel? Asphalt? The tires arent really meant for loose mud but if I were to ride in softer stuff, how low should I go? *How low can you go on this type of clincher setup before worrying about pinch flats?
> *
> Thanks


only you can answer this question. it's totally dependent on how you ride and the terrain you ride on. i weigh the same as you and could probably get away w/ 35ish pretty much anywhere. if you pinch flat ever now and then, that's fine. don't set the pressure so you never flat, it'll be too hard. set the pressure for the ride quality you want the other 99.9999999% of the time.


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## simonaway427 (Jul 12, 2010)

40-50 psi would be a good compromise between speed and comfort.


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## tednugent (Apr 26, 2010)

scottma said:


> This should be an easy one. I nomally ride road bikes with 25C tires and have that down pretty well. I recently built up a Surly Crosscheck for an all purpose Winter/gravel-dirt road whatever kind of bike. I wont be (I dont think so) doing any CX racing with this. Just a fun bike. I have Specialized Trigger Pro 33C tires on Mavic Kysrium Elite rims. I weigh ~ 165#.
> 
> What would be good pressure range for hardpack dirt/gravel? Asphalt? The tires arent really meant for loose mud but if I were to ride in softer stuff, how low should I go? How low can you go on this type of clincher setup before worrying about pinch flats?
> 
> Thanks


It's something you have to experiment. At 190 lbs, on Specialized The Captain Pro, I pinched 30 psi up front.

So.... I would lean to 45 rear and 40 front


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## dcgriz (Feb 13, 2011)

Figuring 25lbs for the Surly makes the total weight 190-195lbs. Assuming 55%/45% load balance between rear and front wheels I would try high 40s on the front and high 50s on the rear to start with and then adjust downwards based on terrain until you pinch flat.
See this http://www.dorkypantsr.us/bike-tire-pressure-calculator.html; not overly accurate but will give you an idea.
I run my Rockhopper 29er with 50mm tires at 40 f and 48 r.


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## cyclevt (Aug 6, 2004)

I'm 170-175# and push 185 fully dressed for cold weather riding. My CX bike is 19-ish#
For clinchers
racing: 35f/40r
Training/general: 45f/50r
Trial/Singletrack: maybe a bit higher to avoid pinch flats

For Tubular (racing only)
28-30f/30-35r

I just run them as low as possible without pinching. Or, run them higher if wanting to go faster on smooth dirt roads or pavement. Under inflated flat tires suck on pavement.
no flats


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## Warpdatframe (Dec 9, 2012)

At 175 pounds I would probably run 40-45 in the front and 45-50 in the back. Personally I'm 120 pounds and I've raced with 22 psi in the front and 25 in the back on clinchers. Just do what feels good to you and test out different pressures.


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## tednugent (Apr 26, 2010)

I am tubeless with the captain 2BR... 30 rear & 28 front


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## scottma (May 18, 2012)

Thanks for the replies everyone. I went out this weekend intending to do a gravel ride. I ran 45F/50R and it seemed pretty good. I ran into a buddy on his road bike so I wound up doing about 20 mi on the road with him and 20 mi on the gravel path alone. They may have felt a bit soft on the road but not bad at all. I'm without a road bike for a little bit and have some road only riding to do with a group this weekend (maybe a lot). The Surly is my only bike for now. Maybe 60/65 for that?


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## Ab24029 (Feb 20, 2006)

I do not race my cyclocross bike and only use it for trail and road riding. I like running the pressure in 65-70 psi range with a cyclocross tire (700-32/34mm). At lower pressure it is hard to keep speed above 20 mph on the road. I also used Panaracer Pacella 32 mm and ran pressures 80-85 psi for fast road riding.


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## cch (Nov 22, 2008)

At 200lbs all in (rider and bike) I have pinch flatted the Specialized Tracer Pro tires at 40psi on a rocky fire road. Running tubeless, by comparison, I only run 30psi with no issues, but that is not an option on your wheels. 

Having lower pressure helps a lot in soft dirt and bumpy terrain. I would make the call based on how bumpy the gravel roads you ride are. 45/50 psi F/R would be the low end of what I would run. If you use latex tubes, you will slightly improve the rolling resistance (as well as resistance to pinch flats), and you might notice that on the road.


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## scottma (May 18, 2012)

Thanks. I hate getting flats especially when its cold out. I'll probably stick to the 45/50 range which seems a pretty safe bet. If I'm using it on the road 65/70.


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