Tire Temperature

[rv_safetyman]

JohnEd, a safety inspection is NEVER a waste of time.  When I walk around the bus I try to use almost all of my senses (vision/smell/touch/hearing) looking anything is abnormal.  Only sense I leave out is taste.  We used to have a compounder (chemist who comes up with the rubber formulas) who could bite a piece of rubber and tell you what synthetic family it came from (neoprene, HBNR, butyl, etc)

As I said in my convoluted previous post, I do it religiously at every stop even though I have the TPMS.  And I stop a bunch since I drink a lot of coffee in the morning and then water to make sure I don't get dehydrated .  

Besides we all need the small amount of exercise we get in the walk around.  Also helps the circulation in the legs.  

Just plain win/win.

Jim

[muddog16]

Being a former racer, I've got a question here?  Where on the tires are you checking the temps?    With a temp gun while racing we checked the tires at the tread  in  three spots across the tires you would be surprised what that tells you its common to have three different temps adjancent to each other on the same tire!   If the tire was over inflated the center temp would be higher, and if it was under inflated it would actually run cooler than the out sides!   There are many factors that come into tire temps!   Also I agree with Jim.........checking the hub temps is probably just as important as the tire temps!

[JohnEd]

Being a former racer, I've got a question here?  Where on the tires are you checking the temps?    With a temp gun while racing we checked the tires at the tread  in  three spots across the tires you would be surprised what that tells you its common to have three different temps adjacent to each other on the same tire!   If the tire was over inflated the center temp would be higher, and if it was under inflated it would actually run cooler than the out sides!   There are many factors that come into tire temps!   Also I agree with Jim.........checking the hub temps is probably just as important as the tire temps!

HALALUHYA!!!!!!!

I say that and all I get is stone silence.  I knew I wasn't sucking all that out of my thumb.  When I was hanging around the pits they had a fast reacting contact thermometer  that they tested the tire with.

Dog,  Is this sort of testing still valid with modern radials?  I would be "surprised" cause it has been so long ago and I forget far better than I used to.  Can you refer to any pub/reference that discusses tire temps and indications?

[rv_safetyman]

Pat, I used to use a temp gun on the blower belts on top fuel cars in the shutdown area as a part of my "blower belt guy" assignment.  I started checking the tires for the drivers.  In this case I did much the same as you did.  Not nearly as indicative because of the tire growth that drag racing tires are designed to have, but it did get the guys to checking the tires as a part of their database.

I check the tires about 2-3 inches below the tread on the side wall.  The tread temperature is not all that important on a truck or bus, since we are not looking for temp differential across a rather narrow tire.  In racing, it can help you optimize tire pressure, but on a truck or bus, the tire pressure should be based on the tire rating for the weight on that tire.

The reason I check the tire in that location is that it lets me measure all the tires in the same location - including the inside dual.  Also, we are looking for excessive fatigue in the sidewall.  The 2-3 inches below tread can be done on most inside duals easily and fairly accurately measures the sidewall temp.

[happycamperbrat]

Wow! You people are running a LOT lower temps then my bus. I live in the truely HOT though, typical summer day is 110 degrees. Last summer I would drive and check my tire temp often with a temp gun. They were running around 145 degrees. Goodyear tires, rated for the highway.

[rv_safetyman]

hcb, I don't think your temps are all that high for the conditions. 

"Rusty" on this board has tire temperatures that are well above that (can't recall exactly what he told me, but it blew me away) and he has not had a problem after a ton of miles.  And that is at much more reasonable ambient temperatures.  We have talked extensively and his tires are properly rated and inflated.  We will be making a trip to the Eagle Rally next month and I will use my gun to verify his temperatures, but our discussions have me believing he does indeed have some pretty high temperatures.

Most rubber products are cured in the low 200* range for a half an hour or so (depending on the product shape and volume).  They continue to cure at a rate that is a function the internal temperature.  A few posts back someone mentioned a tire person had talked about 200* as an upper temperature.  I would have a stroke if my tires got within 40* of that temperature but that is just me and my paranoia.

Jim