Tyre pressures

offcamber

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Keep in mind tire pressure will increase as the tire heat up. I have had my rear go fro 36 to as high as 44 after it was ridden a bit. I have TPMS on my bike so I can see whats going on as I ride. High pressure give you better mileage and tire wear but offers less traction. You gotta feel it out and see what works for you. For me the 32-36 cold rule works.
 

Sierra1

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Joshua TX
THAT has go to be a rough ride at max pressure. IIRC, the max pressure is for max load, and where a tire gets it's speed rating. Which never made sense to me. If I have a car that will do 150mph, and I have the correct tire spec'ed, mounted on the car, but the manufacturer advises to run the tire pressure below the tire's max pressure....is there a chance of tire failure? Now, I understand that most top tire brands are overengineered, but still....
 

Cycledude

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Rib lake wi
I believe the recommended tire pressure’s listed in the owners manual are for cold tires, you really should check pressure before even driving the First mile because tire temperature goes up pretty quick while driving.
 

Jlq1969

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Argentina
It is important to know that the pressure indicated as “optimal” for a tire, refers to the pressure “at sea level”, for which all pressure meters are regulated. The meters work by a differential between the internal tire pressure and the atmospheric pressure. That is to say that if you put 35 psi at 1000m high, (cold) and then travel at sea level and measure again in cold (the next day), you will be surprised to measure 31-32 ... In the photo , it is seen that "at sea level" the atmospheric pressure is 14.7 = 1kg / cm2 .... but at 3000 feet (1000mts / snm) .. the atmospheric pressure drops to 13.2 ... and this alter the pressure differential of the meter and make it measure more while higher above sea level it is( digital or analogic meters) Translating it to S10, if the manual says 33-36, at 3000 feet the meter should indicate 36-39. (approximately)
DD159874-A0DF-46FA-A1F4-534C99824E4D.jpeg
 
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Bokerfork

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Jul 15, 2019
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Saint George, Utah
I live at about 4800' and set all my tires to the recommended pressure when home. This is because I run around most of the time at these higher elevations. If I plan an extended run to lower elevations,i.e. a vacation at the beach, I'll go ahead and pump them up by about 10% just to compensate. A little anal but since I'm checking the pressure in preparation for the trip anyway, it's not a big deal.

Just a little something to stir the pot.
 

Grumpy

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With a TPMS fitted, it's interesting to see how much the pressure changes with heat and altitude. The 33/43 on a mild morning soon becomes 36/46 if the air and road warms up on a sunny day. I have also had pressurs as low as 4 psi down on both due to a cold night, but after half an hours ride they are both up to normal. I always have the rear on the higher pressure as I probably weigh around 225 pounds with kit, and another 40 with boxes and luggage.
 

Clawdog60

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east central "ILL"
THAT has go to be a rough ride at max pressure. IIRC, the max pressure is for max load, and where a tire gets it's speed rating. Which never made sense to me. If I have a car that will do 150mph, and I have the correct tire spec'ed, mounted on the car, but the manufacturer advises to run the tire pressure below the tire's max pressure....is there a chance of tire failure? Now, I understand that most top tire brands are overengineered, but still....
A touch harsh. I guess I’ve gotten used to the feel. I’ll take it for tire wear and mpg. Manufacturers put a fudge factor in at max pressure so I’m not concerned with a couple pounds of pressure from heating.
 

Clawdog60

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east central "ILL"
If you fit other than stock tires with different max pressure ratings or different manufacturer ratings the book recommendations go out the window. Once again ride with what you’re comfortable with.
 
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