Touring - Tire Pressure

I am heading out for my first short tour wednesday 550 miles. I mainly been using my bike for commuting. I am using 32mm Vittoria Randonneur Cross Pro at around 85-95 PSI for commuting. Two fully loaded panniers weight 12 lbs each plus handlebar bag at 3.5 lbs and I weight 175 lbs.

Should I up the PSI fully loaded or just go by feel?

You could drop to 75/70 back/front without risking a pinch-flat. You'll be more comfortable and roll faster on anything but velodrome-smooth surfaces.

What are the roads like where you are riding? The pressure that you are running sounds OK to me. That said, if you will be riding course chip seal roads maybe a bit less pressure might be a good choice to kill the buzz a bit. If the roads are super smooth you might even run a bit more pressure.

lucky1976, While I have 35 mm tires, I've run 65 PSI front and 70 PSI rear with basically the same weights you posted. You can always adjust pressure on the trip, but the 70/75 suggested above should be fine.

Brad

I am heading out for my first short tour wednesday 550 miles. I mainly been using my bike for commuting. I am using 32mm Vittoria Randonneur Cross Pro at around 85-95 PSI for commuting. Two fully loaded panniers weight 12 lbs each plus handlebar bag at 3.5 lbs and I weight 175 lbs.

Should I up the PSI fully loaded or just go by feel?

That's way, way high. I run the exact same tires, at around 70PSI. In three years of loaded touring on everything from glass-smooth pavement to rutted singletrack, I've never needed more.

My touring load is me, at 170 lbs, a Raleigh Sojourn at 32 lbs, and usually around 30lbs of gear, since I carry for both myself and my kids.

Heck, I think the max recommended pressure on the tire itself is something like 70.

EDIT: FWIW, I've ended up following the pressure guidelines at http://janheine.files.wordpress.com/2010/10/bertopresschart.jpg . I was dubious at first, but ended up believing it. None of the 6 bikes at our house have ever pinch-flatted at the recommended pressures, and rolling resistance has always been excellent, within the capabilities of the tire. ( The Rando Cross Pros, for example, are not a tire you ever buy for excellent rolling resistance in the first place. ;-) )

I usually run my tires in the 80s, on 38mm. Assuming the roads are fairly smooth. I have dropped them to 25 when running on soft rail trails. I didn't get pinch flats, but I would ride a small bump up on a bridge as though I was hopping a log. Also, I hadn't thought I had dropped the pressure as much as I had, it only became apparent when I pumped it back up, as my pump had the pressure gage on it. At that point I was running about 300 pounds on the bike, plus the bike weight.

That's way, way high. I run the exact same tires, at around 70PSI. In three years of loaded touring on everything from glass-smooth pavement to rutted singletrack, I've never needed more.

My touring load is me, at 170 lbs, a Raleigh Sojourn at 32 lbs, and usually around 30lbs of gear, since I carry for both myself and my kids.

Heck, I think the max recommended pressure on the tire itself is something like 70.

EDIT: FWIW, I've ended up following the pressure guidelines at http://janheine.files.wordpress.com/2010/10/bertopresschart.jpg . I was dubious at first, but ended up believing it. None of the 6 bikes at our house have ever pinch-flatted at the recommended pressures, and rolling resistance has always been excellent, within the capabilities of the tire. ( The Rando Cross Pros, for example, are not a tire you ever buy for excellent rolling resistance in the first place. ;-) )

After a quick search I found the article that the picture came from. If it is to be belived I am way, like at least 20psi, over inflated for the 1.5 inch tires I run on my commuter. I may have to try lower pressure for a while and see how it feels.

thanks for all the head back... I am going to try 80 on the front and 85 on the back

funny, the Vittoria site lists the Cross Pro as only available in 37mm or labeled 35mm with 60-70psi rating. The heavier Randonneur Trail and Randonnuer Touring tires are listed with 60-90psi rating with the steel bead Randonneur rated 60-80 compared to the folding Randonneur 60-70. I don't get their ratings but a 35-37mm tire with 80psi rolls just fine. I ride a Cross-Check with 35mm Marathon Supremes with any combination of front or rear panniers with my slender 210lbs and haven't felt the need to put more than 75psi in the rear tire. I usually ride 60 front/ 70 rear with 35mm Supremes.
Methinks if your goal is a faster rolling tire instead of picking higher psi with a deeply treaded tire get a slick tire and put it at the right psi. like the Supreme or Randonneur Pro.
If the tire really is 32mm then 85-90psi would be good for the rear with a heavy load.

I just looked up the Marathon slicks and it read they were only good for 50-70. Another similar Marathon was good for 50-85. That sounds more like what I was riding the Slicks at. Normally tires that cap out at say 65-70 are not built to take the higher pressure, if they are road sized. They are probably comfort bike tires, and they just keep inflating like a balloon the more air you add.

Just checked some NOS Slicks I have, they are marked min 55, max 95. But this site says 45-70.

http://www.adventurecycling.org/store/index.cfm/product/452/schwalbe-marathon-slick-hs-341-tire.cfm

So it probably pays to check the tire you are actually riding.

thanks for all the head back... I am going to try 80 on the front and 85 on the back

I just realized where I'd seen your name before - are you going to be starting on that Lake Ontario circuit you had asked about a couple months ago? The weather here in upstate NY has been absolutely gorgeous for riding the last couple of days.

I just realized where I'd seen your name before - are you going to be starting on that Lake Ontario circuit you had asked about a couple months ago? The weather here in upstate NY has been absolutely gorgeous for riding the last couple of days.

I am actually leaving tomorrow morning....leaving from Amherst, NY heading to Wilson, NY and the east along Lake Ontario. I m planning on stopping in either Sodus Point, Fair Haven, NY or Oswego, NY the first night and then up to Canada thursday and on....

I just pickup a '48 Schwinn Balloon Tire bike. The tire pressure is 55 lbs MAX. Imagine that! It sure does ride smooth.

200lbs. my 32mm tires for my commuter gets rear 65 and front 55.

With a touring load aboard , you feel the rolling resistance go up,
when the tires are soft.

I bring a Gage..