Tire Temperatures

[Bob_Roller]

Got a non-contact infared thermometer this week, using it check my home air conditioning/heating system .

I checked the tire temps on the R65 this morning .

Air temp at 0500, 94 F (34 C), tire temps front and rear 101 F (38 C), road surface temp 106 F (41 C) .

After getting to work, 11 miles, 1.5 miles of surface streets, 9.5 miles of urban expressway, 70 mph .

Front tire 121 F (49 C), rear tire 130 F. (54 C), road surface temp at work, 102 F (39 C).

The ride home should get interesting, forcast temp for around 1500, is 113 F (45 C).

[montmil]

Did you check tire pressures at the elevated tire temps? Now that, too, would be interesting information.

[Bob_Roller]

I checked the tire pressure yesterday afternoon at around 1500, I move the bikes around, so the one I take to work on Saturday morning  is next to the garage door and I don't have to do any moving early in the morning, the front and rear pressures were 37 psi .

I'll do  a pressure check when I get home today .

[Barry]

It'll be interesting to see if the pressures follow the 10/10 rule or 10/20 rule or more likely something in between.  If not the full 10/20 I would still expect you to have a bigger % rise on the rear.

I got 9.5/17.4

[Bob_Roller]

I checked the tire temps before I left work at 1430, both were 124 F (51 C) .

This is under covered parking at work, there is an 80 acre city parking lot covered in asphalt just to the east of the employee parking where I work, that probably explains the high temp, as the temp at Skyharbor airport where I work, was 111 F (44 C) at 1425, road surface temp 165 F (74 C).

Got home pulled the thermometer from under my mesh jacket and got 'ERROR' on the display, removed the batteries and reinstalled them a few minutes later, no help .

Checked the tire pressures, front and rear were at 44 psi .

I placed the thermometer in the freezer and 5 minutes later, it worked fine, so I know next time to put the thermometer in my packpack and maybe it will work when I get home !!!!!

Tires had 'cooled' down to 120 F (49 C), when I checked them .

I'll try this again, I'll take the tire pressures before I leave for work, then when I get there, same for the return trip home .

[montmil]

Good Lord, Bob!  Riding around in the dark just outside the Gates of Hell...

Now I'm more concerned about you.

[Bob_Roller]

But it's a 'dry heat' , that makes it tolerable !!!!!


A joke I just hear this week .

A priest was asked by his superiors, why he had so few converts in Phoenix .

The priests reply, ' after one winter here, heaven has no appeal, after spending one summer here, they have no fear of hell' .  

[raypond]

Aren't those infrared thermometers beaut. I got one last week and went straight for the engine. Now I can worry about why the right cylinder is hotter than the left (125/110). I'll do the tyres next time I'm out on the bike.

[georgesgiralt]

Difference in barrel temperature is manly due to a difference in the amount of gas coming in. Too lean a mixture and the cylinder runs hotter.
Often playing a bit with the idle mixture screw helps a lot...
Of course, I suppose the two spark plugs are the same and in the same state. And valve play is also equal on both cylinders...

[tvrla]

Are these the Harbor Freight thermometers?

[Bob_Roller]

Why yes it is in my case .

I had a 20 % off coupon, thet were on special, so I got it for $15US .

Checked it with a calibrated infared thermometer at work and it was within a 2 degrees F  of the calibrated thermometer .

[Bob_Roller]

Tried this again this morning .

Air temp at 0510 was 78 F. and 84% humidity, road surface temp 87 F, front and rear tire temp 90 F .

Front and rear tire pressures 35 psi .

Got to work, front tire temp 115 F, rear tire 121 F .

Tire pressures, front 36 psi, rear 38 psi .

A longer trip may have gotten the tires up to a higher temp and pressure, this was 11 miles .

[montmil]

Wow. Large differences in tire temps due to road and ambient air but not such a big swing in tire pressures.

Appreciate you taking the time to monitor and post your test results.

You da man, Bob. [smiley=dankk2.gif]

[Bob_Roller]

I may take a longer trip tomorrow morning, being a holiday weekend and getting out by 0500 traffic shouldn't be a problem .

Just looking at the pressure on the front tire while hot, the pressure may need to come down a bit .