Hot tire pressure

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double_entendre

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I'm in the middle of a few thousand mile road trip and was checking tire pressure somewhere in Montana/Wyoming today. Normally I follow the sorta-guidline of 42PSI front, 44PSI rear on a Pilot Sport front and Pilot Power 2 rear.

When I checked the hot pressure--it's toasty; 90 or so--the rear had blown up to 50+ PSI. :blink: I don't know how much "plus" because the gauge only goes to 50. The front had kicked up as well, but not as much.

Anyway, I dropped the hot pressure down to about 46PSI rear and 45 front and am going to check them out tomorrow before I get on the road again.

Comments welcome, but also throwing it out as a "gospel might not be" kinda warning as well. I'm pretty sure that 50+PSI is not recommended and no one wants a rear blowout in mid-nowhere Wyoming.

Oh. And I rate a dumb-shit parking lot tipover icon for a gas station mishap in Moose Jaw. No harm other than a scratched saddlebag. Battle scars.

Rancho

 
Hot temperature doesn't matter because tires become very warm and more pressurized when you run them. They're designed to be set at a cold ambient temperature. Don't worry if they get to 50 or 60 or whatever because they're designed for that.

Seasonality does have a little affect, but hopefully you didn't set them in the middle of winter when it was 40 degrees in your garage and forget to adjust for 90 degrees. But, even if you did forget with that extrem you'd have about a 5 psi change. 10 degrees temperature equals about 1 psi difference.

...and this has been discussed a bunch of times before. ;)

 
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This is why we don't get real oil pressure gauges any more. ;) Stop checking it hot, set it cold and ride happy. Some argue a 10% change from cold to hot is what to aim for, but you've added temps too. 10%+ Iggy's 5 psi would be 9.5 psi ideal pressure rise, or in the range of what you're seeing. Gonna be too low in the morning when you check it cold though.

 
This is why we don't get real oil pressure gauges any more. ;) Stop checking it hot, set it cold and ride happy. Some argue a 10% change from cold to hot is what to aim for, but you've added temps too. 10%+ Iggy's 5 psi would be 9.5 psi ideal pressure rise, or in the range of what you're seeing. Gonna be too low in the morning when you check it cold though.
Thanks, guys. :) I figured there was a good chance it had been NEPRT'd (new term?), but reading 10,000 posts to find it.... ugh.

Gonna see how much closer to SoCal I can get from Casper, WY today.

Ride safe!

Rancho

 
I have the Smartire pressure monitor system and it's interesting how much the tire pressure changes with temp. and riding. Before leaving FL, on my trip to Alaska, I set the tire pressure at 40-42 when it was around 75 degrees. On many mornings in Canada and Alaska, with temps in the high 30's, tire pressure would display around 34-35-36. Later in the day after riding several hundred miles, if it reached 60 degrees, the pressure would be back around 40. Back in the lower 48, with higher day temps, the tire pressure would go 43-44 or higher after riding.

 
Also, for every 1000 feet gained in altitude tire pressure goes up 1/2 lb. So if you ride up 10,000 feet and it gets 50 degrees warmer since you last checked it that's 10 psi more pressure.

 
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