Tire Pressure in Hot weather

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paste007

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I've been inflating my tires to 40(f) and 42® when they're cold.

Is it advisable to run lower initial pressures if you know that you are going to be riding in 100+ temps for several hours? If so, is that some kind of guide or chart noting how much to adjust the tire pressure for increases in the ambient air temp?

 
I wouldn't worry about it unless you're losing sleep at night or already fixed your sidestand.

You're talking about 1 psi per 10 degrees per this page. (and yes an automotive page is applicable to motorcycles in the case of air pressure)

And it's not the ambient air temperature difference, but tire temperature difference that's more important anyway. You cruise on the slab at 100 degrees vs. through the twisties at 70 degrees air temperature....and I *bet* your warmer tire is the one in the twisties.

 
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PSI measured on cold tires first thing in the morning should be fine. You'll find that you add/remove PSI based on temp changes but the PSI target point stays the same.

More critical is that you change out the winter air for summer air (and vise versa) every 6 months.

 
Yes, a don't forget about relative humidity (not-to-mention: absolute humidity).

Maybe a weather-station would be a good idea? Or, at least a wet-bulb hygrometer? :eek: :unsure:

[/sarcasm]

 
Hey, do you need a special tool for exchanging the winter air for summer air and vice-versa without deflating the tire first?

Ed :rolleyes: :rolleyes:

 
Use a nitrogen based air and you won't have any problems.

is it friday yet?

 
What about helium? Will that make the bike lighter? Anyone know what oil to use?

Friday comes earlier every week.

 
What about helium? Will that make the bike lighter? Anyone know what oil to use?
Friday comes earlier every week.
Why you wouldn't be referring to the world-reknowned Amsoil, would ya be? I tried the Helium once, it fooked up the sound of the tires real bad, had to switch back to air. High pitch FJR tires worked better than the deer-chaser, though.

 
I went to change out the air in the tires from winter to summer air one year, but I forgot that I still had winter air in the compressor tank, so I had to do it all over again. Oh man, did I feel silly. :D

 
A very good rule of thumb is to set your tire pressure cold, that means that they at least set over night before you set pressures. Go ride as you normally would whether it's 1 up or 2 up ride for at least 30 mins. when you get back check the pressure again it should go up no more than 10% in front and no more than 20% in the rear. If it is over those percentages you need to run more pressure to keep the tires from over heating. The heavier the load the more pressure is needed to keep the temps down. Heat is the enemy of a tire less pressure will cause more heat. On the flip side of the coin proper heat is what helps the tire stay planted. If you push it on a cool day with cold tire you will soon learn that tires need to be heated properly in order to their job of gripping properly.

 
Whollly ****** ****!!!!!!!!!!!!!!!!!!!!! I see three posts here already tonight that If somebody would have actually read the newbie instructions......... Woulda, coulda, found by enlisting the help of the Damn SEARCH function!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

****!

Whats normal for heat, and this are fukin a double redundancy times six!!!!!!!!!!!!!!!!!!!!!!!!!!!! [SIZE=8pt]hows that 4 makin cents Howie![/SIZE]

OK who's gonna be first to say I'm an *** for bein intolerant of ignorance????

Damnit all! read and follow directions when ya sign up!!!!!!!!!!!!!!!!!!!!!!

***!!!!!!!!!!!!!!!! :angry:

:jester:

 
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A very good rule of thumb is to set your tire pressure cold, that means that they at least set over night before you set pressures. Go ride as you normally would whether it's 1 up or 2 up ride for at least 30 mins. when you get back check the pressure again it should go up no more than 10% in front and no more than 20% in the rear. If it is over those percentages you need to run more pressure to keep the tires from over heating. The heavier the load the more pressure is needed to keep the temps down. Heat is the enemy of a tire less pressure will cause more heat. On the flip side of the coin proper heat is what helps the tire stay planted. If you push it on a cool day with cold tire you will soon learn that tires need to be heated properly in order to their job of gripping properly.
The old percentage gain when the tire is hot rule doesn't really apply any longer with modern radial tires. This was more of a guideline with bias-ply tires. Set your tires cold based on your riding, comfort and max load needs, and just ride. :yahoo:

 
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