[ICEBRU]

Quick question for the masses. How much does the tire temp rise when your warmed up and riding. My 07 yukon has air pressure reading in the dash. They start out at 30 and raise to 33 after 6 or so miles. Does a motorcycle tire have the same increase or more, or less. Mother honda says to run 36 in ft and 40 in back,I assume thats cold. For 20 years on all my bikes I have ran 40/40. any input????? :?

 

[GoldWingrGreg]

They'll increase in temp about the same as a car. It's all relative to how you drive/ride and how hot the payment is.

The most important thing is to follow Honda's air pressure recomendations. My '04 calls for 36 and 41 cold. Cold is a tire sitting for at least 4 hours and driven less then 1 mile.

 

[Rob(in S.C.)]

41/41 here in my E-3's from 12K when my 'Stones were shot. Have over 13K on the E-3's now, no noticeable cupping on the front.

36 seems awful low for the front, and sure to accelerate cupping.

JMHO, of course! :wink:

 

[Wanderer]

The most important thing is to follow Honda's air pressure recomendations.

Why do you think that's so important? Most of us don't follow Honda's tire pressure recomendation.

For 20 years on all my bikes I have ran 40/40. any input?????

Most folks run 40-41 in both front and rear. Except for a Bridgestone front - most believe 38 is the right pressure for that tire. YOMD

 

[GoldWingrGreg]

Because the DOT requires the manufacture of a vehical to list the needed air pressure for the tires on any particular vehical. This is done after extensive testing for proper braking and handling. Certainly gas milage, tire wear, cupping, tire noise, and other factors are taken into account when they stamp the tire pressure sticker, but all other criteria take a back seat to breaking and handling.

Don't forget, your contact tire patch is smaller with higher pressure.

 

[gcgst1]

I just happened to check this the other day. I had just pumped the front to 39 psi (cold). I went for a ride and hit an uneven patch which threw me around a little. I thought to myself, did I screw up when I inflated the front? Did the valve stem stick or something, because it felt strange, so I checked it after I returned home from about a 20 mile loop. It was up to 44 in the front.

 

[GhostRider]

It'll climb more than you might think on a hot day at highway speed.

The thing to remember is all specs for tire pressure are normalized at 65 degrees F. So if you fill your tire to the specified 41 lbs on a 65 degree morning you're good to go, but if its 85 you need to put more air in the tire to compensate for the higher temp. A good rule of thumb is 1 psi for every 10 degree rise above the 65. So at our 85 degree morning you should put 43 psi in the tire to establish the 41 standard spec. It does make a difference.... particularly if you're using a SmarTire system to track and report your tire temp and pressure.

I've actually checked the 43 psi added at 85 degrees again later when the tire had cooled to 65 degrees. The 43 read 41 at 65 degrees so the rule of thumb appears to work fairly well.

 

[WinginHunk]

I am no expert, but I believe the recommended pressure by Honda would be for OEM tires. They probably also take into consideration the comfort level, which at higher pressure would result in a harsher ride.
If you use a tire by a different manufacturer, I would pay more attention to the recommendation by the company that makes the tire. For example, my tire of choice is Metzeler and they recommend 40 front and 42 rear.

http://www.us.metzelermoto.com/tyre...Goldwing&confirm=true&IMAGE1.x=38&IMAGE1.y=11

 

[upssnowman]

one up cold 41 front 41 rear ,,,,,,two riding 41 front 43 rear cold on cent stand, I get way more miles then most on tires I check almost every ride

 

[Green Horn]

Has any one heard of the 10percent rule for tire pressure.

If the tires are infalted 10percent of the cold tire reading they are properly inflated. If they are more then 10percent you need to add more air at the cold tire reading. If it is less then 10 percent you need less air in the tire at the cold tire reading.

 

[Wanderer]

If the tires are infalted 10percent of the cold tire reading they are properly inflated. If they are more then 10percent you need to add more air at the cold tire reading. If it is less then 10 percent you need less air in the tire at the cold tire reading.

I think what you are saying is, if the tire pressure is within 10% of where you want it, you don't need to add air. If more than a 10% difference, then add air?

I guess it'd be your choice. With this rule, at a normal pressure of 40 psi, your pressure could vary from 36 - 44 psi. Without knowing I had a "rule", I guess mine would be 5%, rather than 10. To each his own.

 

[mcrider007]

Has any one heard of the 10percent rule for tire pressure.

Yes, and the 10 percent rule really means that your cold air pressure should be within 10 percent of the pressure when the tires are fully warmed up -- and the "hot" pressure should be measured when the tires are actually hot, not in your garage after a ride, when you have ridden for several miles at 35 mph to get home. The 10 percent rule will generally give a tire temperature that is a good compromise between traction and long tire life.

The 10 percent rule does not seem to work very well for Goldwing tires since they seem to be designed to run "hot" at 48-52 psi. Why? My guess is that the Goldwing tires are composed of a pretty hard rubber compound and they need to be heated to a higher temperature for adequate traction (every 10 percent of pressure increase represents about a 50 degree rise in the tire's inner temperature).

 

[Green Horn]

Thanks mcrider I know I explained this poorly but your input has helped me out. I hope it has help KEVBRU also

 

[Wanderer]

(every 10 percent of pressure increase represents about a 50 degree rise in the tire's inner temperature).

I thought more internal pressure = less operating temperature? With more pressure the tire will flex less. Less flex = less heat?

 

[mcrider007]

(every 10 percent of pressure increase represents about a 50 degree rise in the tire's inner temperature).

I thought more internal pressure = less operating temperature? With more pressure the tire will flex less. Less flex = less heat?

Sidewall flex creates heat which expands the air in the tire in direct proportion to the temperature change from absolute zero (which is minus 460F). At 70F it takes a 53 degree temperature increase to expand the air (and the pressure) by 10 percent. Eventually the tire pressure will get great enough that the sidewall will no longer flex and create heat but as soon as the air starts to cool the pressure will drop and the sidewall will again flex to raise the temperature and air pressure back to the previous point.

Cold tire pressure is a way to control the tires operating temperature and the higher the cold pressure, the less heat that will have to be generated by sidewall flex to reach the tire's operating pressure. Heat is not always bad, its just a tradeoff between traction and tire life. In the summer it can be hard to keep a tire from overheating, in the winter it is sometimes hard to keep the contact patch warm enough for decent traction because the pavement it is running on can be so cold (the tire will be heating from the inside from sidewall flex and cooling from the outside because of contact with cold air and pavement).