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View Full Version : Do you set tire pressure to the garage temperature before you ride?



stevenolts
09-13-2016, 07:35 PM
I have a question that has come up since the weather has started to get cooler. I have always used the garage ambient temperature to set my tire pressure before I ride. Since I have the FOBO I am able to keep better control over the tire pressure. I have started to wonder if I am doing this correctly since the garage temperature is changing with the weather but the running / road temperature is probably closer to the same all year since it is caused by friction. I may be wrong about that since I don't have evidence at this time. What are your thoughts about this. I know I am probably overthinking this but we are all crazy about our bikes. I think the most important thing is to set the pressure before I ride not after the tires heat up.
Steve

jm21ddd15
09-13-2016, 07:40 PM
Yes, set the air pressure before you ride and the tires get hot. Part of the Pre- ride inspection. :yes:

lgjhn
09-13-2016, 07:45 PM
I have a question that has come up since the weather has started to get cooler. I have always used the garage ambient temperature to set my tire pressure before I ride. Since I have the FOBO I am able to keep better control over the tire pressure. I have started to wonder if I am doing this correctly since the garage temperature is changing with the weather but the running / road temperature is probably closer to the same all year since it is caused by friction. I may be wrong about that since I don't have evidence at this time. What are your thoughts about this. I know I am probably overthinking this but we are all crazy about our bikes. I think the most important thing is to set the pressure before I ride not after the tires heat up.
Steve

Everyone has an opinion on it, but I know for fact that tire pressure changes with temperature, and the pressure is supposed to be set "cold' per most manufacturers. I set my pressures based on 68 degrees and add roughly 1 psig for every 20 degree of temperature increase. So if I want 41 psig in the tire at 68 degrees and my garage is 88 degrees, then I would put 42 psig in it. Some of my rider friends just set it cold for whatever the garage is at that time. I may be doing it wrong too, but that's kinda how I do it.
And yes, as stated above, it's part of my pre-ride check list.

willtill
09-14-2016, 06:51 AM
Agree with the opinions. But this is ludicrous... meaning that you try to adjust cold tire pressures based upon expected ambient temerature swings during the day. With the way weather changes around here in Maryland, I would be constantly on my hands and knee's adjusting cold starting tire pressure every morning.

I pulled the below off of Tire Rack's website:

http://www.tirerack.com/winter/tech/techpage.jsp?techid=147

Maintenance Tips to Increase Tire Performance, Life and Durability

Check and Adjust First Thing In The Morning. Set according to the vehicle manufacturer's cold tire pressure(s) recommended on the vehicle's tire placard or in its owner's manual. This must be done before rising ambient temperatures, the sun's radiant heat or even driving short distances temporarily warms the tires.
Accommodating Variables

Indoor-to-outdoor Temperature Variation. Significant differences between the conditions tire pressures are set (the warmth of an attached garage, heated garage or service shop) and in which the vehicle will be driven (winter's subfreezing temperatures) requires inflating tires 1 psi higher than recommended on the placard for every 10° F difference in temperature between interior and exterior temperatures.

Afternoon Ambient Temperature Increase.* Set 2 psi above vehicle manufacturer's cold inflation recommendations when installing new tires or if the vehicle has been parked in the shade for a few hours.

Tire Heat Generated While Being Driven (or at speeds of less than 45 mph).* Set 4 psi above vehicle manufacturer's cold inflation recommendations.

Heat Generated While Being Driven Extensively (or at sustained speeds greater than 45 mph).* Set 6 psi above vehicle manufacturer's cold inflation recommendations.

Do Not Release Hot Tire Pressure if any of these variables could be the cause of measured tire pressure exceeding the maximum psi branded on the tire's sidewall by the 2, 4 or 6 psi indicated above for the various conditions. This temporary pressure increase is expected and designed into the tire's capabilities.

Note: Tires on a parked vehicle exposed to direct sunlight will appear over inflated due to the heat absorbed from the radiant energy of the sun. Pressures cannot be accurately set on these tires until all have stabilized in the shade.

I just try to maintain a consistent cold starting tire pressure that stays compliant with not exceeding the tires max psi rating (example 40psi front, 42 psi rear) regardless of the expected ambient temperature for the day. Tires are going to heat up anyway when you're using them.

bob109
09-14-2016, 07:40 AM
After my 6 sits all night in my garage (un-heated) I perform a pressure check with my "Analog Slime Pressure Gauge". With no fuss or ado, I ensure the front Bridgestone BattlAx BT45 is set to 40 PSI and the rear General G-Max is set to 43 PSI. Regardless of the outside temp my garage stays at a near constant of 65 degrees in the summer months. Heading to Florida in mid Oct., upon my arrival, I check and usually have to make a minor adjustment to pressure. Not so much caused by a difference in "heat/temperature" but, more so, because of the difference in altitude. 1835 ft. above sea level in Pa. versus 10/50 ft. in Florida. I like to "set and forget" with a occasional "cold tire check". I'm anal enough without adding "tire pressure correctness" to the list:shock:

Wing'n it
09-14-2016, 08:55 AM
I have the TPMS system on my bike from Garmin on my GPS, I check the tire pressures before every ride and if they are within a pound or two I don't do anything but go ride. I have a digital tire pressure gauge that I like really well and it's accurate so I use it to set the pressure and the GPS is spot on with the gauge. I did find out that the TPMS is a real life saver as I got a low tire pressure warning once for the front tire and it turns out I left the sensor a little loose.

opas ride
09-14-2016, 09:54 AM
Agree with the opinions. But this is ludicrous... meaning that you try to adjust cold tire pressures based upon expected ambient temerature swings during the day. With the way weather changes around here in Maryland, I would be constantly on my hands and knee's adjusting cold starting tire pressure every morning.

I pulled the below off of Tire Rack's website:

http://www.tirerack.com/winter/tech/techpage.jsp?techid=147

Maintenance Tips to Increase Tire Performance, Life and Durability

Check and Adjust First Thing In The Morning. Set according to the vehicle manufacturer's cold tire pressure(s) recommended on the vehicle's tire placard or in its owner's manual. This must be done before rising ambient temperatures, the sun's radiant heat or even driving short distances temporarily warms the tires.
Accommodating Variables

Indoor-to-outdoor Temperature Variation. Significant differences between the conditions tire pressures are set (the warmth of an attached garage, heated garage or service shop) and in which the vehicle will be driven (winter's subfreezing temperatures) requires inflating tires 1 psi higher than recommended on the placard for every 10° F difference in temperature between interior and exterior temperatures.

Afternoon Ambient Temperature Increase.* Set 2 psi above vehicle manufacturer's cold inflation recommendations when installing new tires or if the vehicle has been parked in the shade for a few hours.

Tire Heat Generated While Being Driven (or at speeds of less than 45 mph).* Set 4 psi above vehicle manufacturer's cold inflation recommendations.

Heat Generated While Being Driven Extensively (or at sustained speeds greater than 45 mph).* Set 6 psi above vehicle manufacturer's cold inflation recommendations.

Do Not Release Hot Tire Pressure if any of these variables could be the cause of measured tire pressure exceeding the maximum psi branded on the tire's sidewall by the 2, 4 or 6 psi indicated above for the various conditions. This temporary pressure increase is expected and designed into the tire's capabilities.

Note: Tires on a parked vehicle exposed to direct sunlight will appear over inflated due to the heat absorbed from the radiant energy of the sun. Pressures cannot be accurately set on these tires until all have stabilized in the shade.

I just try to maintain a consistent cold starting tire pressure that stays compliant with not exceeding the tires max psi rating (example 40psi front, 42 psi rear) regardless of the expected ambient temperature for the day. Tires are going to heat up anyway when you're using them.
+1 my friend..If I worried about a couple psi changes every time I rode my bike or "aired up" the tires worrying about inside or outside temps, I also would be on my hands and knees screwing around with tires most of the day...I doubt anyone of us that ride can say for sure they have the "exactly correct" psi in their tires as gauges are generally not that accurate....Just check the tires, air-up to what you feel comfortable with and "Ride On"....

98valk
09-14-2016, 10:52 AM
I would think that the goal is to have the same running pressure in the tires all year round. My tires are going to be a lot warmer in the 100 degree summer than in the 40 degree winter days.

So, I would set the "cold" pressures the same any time of year expecting a similar increase once warm/hot. Close enough for government work. My new TPMS may reveal something else to me. We'll see ....

willtill
09-14-2016, 11:27 AM
I would think that the goal is to have the same running pressure in the tires all year round. My tires are going to be a lot warmer in the 100 degree summer than in the 40 degree winter days.

So, I would set the "cold" pressures the same any time of year expecting a similar increase once warm/hot. Close enough for government work. My new TPMS may reveal something else to me. We'll see ....

Exactly. That's what I try to do. :yes: