Tire PSI Cold vs. Hot

[jeckyll]

Missed the fact that this thread came back up

Checkswrecks: great info, thank you for putting all that together.

Eric: on my trip to the North last summer, I found that the Tractionator GPS was uncomfortable at 42 psi. I was happy with it at 39 psi and didn't worry about what that would do to the tire. You've seen the photos from that trip, I was pretty loaded, but not 2 up. Not sure of my total weight actually, but I'm probably 210 - 220 with gear and then add luggage. It was the first time I changed tire pressure to get more comfort on the SuperT, something's a bit different about that MotoZ.

Chris: I used to start my sportbikes at 32 / 36 and then experiment to ensure I got the most traction. In the summers, I'd run 30 / 33 for spirited rides, same as track days, and had better traction than at 32 / 36 once the tire warmed up (ZX9R - at knee dragging speed, not touring). My current 'sporty bike' (Aprilia Tuono) I run at higher pressures (33 - 35 front / 37 - 39 rear) and it seems happy there. Note that I tend to start with the manufacturers recommended pressure and then adjust based on how the bikes behaves, on roads I know inside and out

 

[Jlq1969]

Well this thread definitely went off the rails but I was searching to find some middle ground. Sorry for the rehash
On my west coast trip last September I road 800 and 600 miles in 2 days to seattle. Bike was not too heavy cause I used almost everything I brought. But I'm a big guy and maybe with all my farkles and gear it's a total of 375 lbs. I was Running k60 nicely broke in with 300 miles. First day was 400 miles of hurricane and remains a blur of water. Day 2 I checked air in salmon Idaho filled to 41 psi as recommended in my manual. It was 40 degrees. I really noticed the tire had worn more then I was expecting. In have tpms and 75 miles into my I 90 section I looked down and noticed rear pressure at 54lbs at 85mph. It was about 70 degrees. I swung into next rest stop to double check and the gauge confirmed. Also I really noticed tire wearing. I dropped pressure to 42 hot and continued another 400miles.

I truly felt that I had less wear. The next AM my cold psi was 32. I road conservative until psi hit 36. (About 5 miles) then hit interstate and pressure hit 41 and ranged 38-41 for the next 4000 miles. Temps usually around 55-65 degrees. My wear slowed dramatically

I'm a bit of a tire geek and get everything that is supposed to be. I'm good now starting a little low and easing into my ride. I was looking to see if anyone else had similar results but I don't see any......

Maybe ill do some temps to add to those psi if it every quits freaking snowing!

I don't know how high is the place from where you started. But you should bear in mind that with those miles you did, and the places you traveled (started, somewhere in Idaho, Seattle), you have probably reached 2000m above sea level and dropped to 0m in Seattle. Regardless of the temperature, which increases pressure as the tire heats up, the height above sea level will do the same effect.

Tyre pressures

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...

www.yamahasupertenere.com

 

[Pdrhound]

Same results ending and starting at home this week. Try it. Start cold. Go 75 mph for 30 mins, stop and check. It will drop 3 lbs in 3 mins so be quick. Probably should be a lukewarm day at least