I have a 2017 CVO Street Glide. I see what the manual says for tire pressure front and rear. I'd like to know where you guys are running your bikes. As the tire heats up, I see the tire pressure increase on the rear by around 10 psi.

Trying to a) not have the sensor go off for low pressure when tires are ambient air temp and b) get the best mileage out of my rear tire. I am interested in mostly the rear tire, but would like to hear where you run the front at ambient as well.

 

Set to the manual... 36/40

 

Mine are also at 36/40. My back pressure runs 46-48 on a hot day, front around 38-39

 

^^^^^ Yep

 

Thanks everyone. I will try running at 36/40 cold.

 

There IS a little method for determining cold pressures based upon cold / hot pressure differentials. According to that method your rear tire cold pressure may be a little low at 40.

If you're interested, try increasing your cold tire pressures, by trial and error, in 2 psi increments until the cold / hot measured pressures differ by roughly 10%. The cold tire pressure which results in this differential is optimal, according to the method.

I use this for my Breakout's 250 rear and the results in handling and tire longevity for those chubby, short lived, tires is substantial. YMMV

 

Owners manual says check cold tire pressure and add 1psi for each 10 degrees temp above 68. Like the TPMS feature and when riding in hot climate at high speed pressure changes a lot which is normal due to heat builds up in the tires.

 

Use of the TPMS system could not be simpler: adjust the tire pressure up or down until the TPMS system displays the correct nominal pressure. It does not matter what the ambient temperature is or whether or not the tires are warm or cold.

Since you have to ride the bike to get a reading, it's necessary to take note of the pressures indicated by the TPMS before you stop riding to adjust the pressure. This might be when you come back from a ride or when you stop on the road during a ride. You only need to make note of the difference between TPMS "indicated" and recommended "nominal" and remember it.

When adjusting the pressure using a hand-held gauge, you do not care at all about the gauge reading. You only care about making the adjustment to account for the differences noted when you stopped the bike.

For example, the TPMS shows 40 PSI for the rear and nominal is 42 PSI. When I check the rear with my hand-held gauge, it might be a hot day and the tire might be warm. The gauge might read high in general. I read 49 PSI. But, according to TPMS, I need +2 PSI. So I inflate to 51 PSI by my hand-held gauge. When I get back on the bike and continue riding, the TPMS will show 42 PSI.
I also use a Meiser Accu-Gauge on my bikes and auto tires. My Honda dirt bike has no TPMS. Typically, the gauge reads 3-4 psi lower than what is shown on the TPMS (but I don't know this until I'm already geared up and riding as there is no reading until rolling). If low enough to justify adding air, I add an extra 4 psi to account for the difference. Interestingly, I've noticed that both the ST and the GS tend to drift downward 1-2 psi after running at highway speed for even a short difference.

I was on a bike tour a few years back with a friend who is OCD about tire pressure. He would not start the day until he had his K1600 GT dialed in exactly to OEM specs. It was a 20-minute process every morning as he wheeled in and out of a gas station, adding and subtracting air until the TPMS was spot on. After several mornings of this routine, I asked him how he knew the TPMS was accurate. The look on his face was one of puzzlement and frustration. I thought he was going to kill me.

I don't think 3-4 psi is critical to safety, fuel mileage, handling, etc., so I use the TPMS like TireMinder https://mechanicguides.com/best-tire-pressure-systems/ more as a monitor while riding. If after a lunch stop, I were to see a 10 psi decrease, I'll be looking for a screw in the sidewall.

 

way to resurrect a year old thread........but it's right on the tire for pressure when cold!!

 

Bingo. Good job.