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Discussion Starter #1 (Edited)
I just installed my system this past weekend and have a question for those who have also installed it. With the pressures at the recommend 42F-48R how hot does your rear tire get? With the outside temp at about 85-90 and rolling down the road at 70ish my rear tire was at 130 degrees. That's not far off from the 180 degree warning mark. I also looked on their site for more info on the compensated pressure deference... still fuzzy on that reading.
 

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Let me apologize first, because I do NOT have the Smart Tire installed...although my GT will have it OEM-fitted as soon as it becomes available. Just wanted to throw in my 2 cents. 130° and 180° are worlds apart when it comes to tire temps. I am surprised however that the warning light comes on at 180°. Perhaps someone much more 'in the know' can shed some light. But that seems AWFUL low. I thought motorcycle tire temps could safely reach over 200° without problems. In fact, most tire warmers that are used at the track run at 175°. Perhaps all of my information is based solely upon track tires...and NOT street tires.
 

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Tire Temperature...

Running two up - rear at 48, front at 44 - 110 degrees outside temp, running 75 MPH - who knows what the road temp was.

Rear tire never made it past 160 degree mark - front tire never made it past the 130ish mark. Pressures where around 49 front, 54 rear - give or take a pound or two.

So I think 180 is a reasonable alarm point (remember this is related to pressure as well - at 180 degrees your tire pressure is probably pretty high anyway).
 

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Smartire

Gino said:
Running two up - rear at 48, front at 44 - 110 degrees outside temp, running 75 MPH - who knows what the road temp was.

Rear tire never made it past 160 degree mark - front tire never made it past the 130ish mark. Pressures where around 49 front, 54 rear - give or take a pound or two.

So I think 180 is a reasonable alarm point (remember this is related to pressure as well - at 180 degrees your tire pressure is probably pretty high anyway).
I get the same numbers as Gino. Ideally you should always have 0 deviation.
If you have a negative deviation,it is telling you that you have an underinflated tire regardless of what the pressure shows on the Smartire. Don't trust the deviation shown on start-up. Always wait a few minutes until the system recalculates the number.

Dan Martin
 

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When traveling between Las Vegas and St George, my rear tire read well over 190 degrees. That was two up, fully loaded, 80+ on I-15 in 115 degree air temps. The tire seemed fine on that trip and several others, though I did monitor it for quite a while. Yes it was a BT020, and no, it didn't delaminate or bubble.

The temp-compensated thing is easy. As a gas heats up, its pressure rises (more energy in the individual gas molecules). So a tire that reads 48 psi at 60 degrees ambient temp will increase in reported pressure as it heats up during use. The SmartTire reports actual pressure, but also does a calculation and shows if the pressure would be high, or low, or spot-on if you removed the temp-related pressure component.

Sorry, that last paragraph sounds an awful lot like engineer speak, but it is pretty simple. Maybe it's just not simple to explain. :)
 

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Discussion Starter #7
Thanks everyone. I though that is what the temp compensations was doing. Just seams weird that cold they are spot on then as they get hot and the pressure goes up the monitor is telling me they are (-) now. Glade to hear that the Stones are holding up to 190+. I too am a fan of the Stones. I'll take the traction over milage any day.
 

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messenger13 said:
I just figured you copied & pasted from their website.
Nah, my brain actually works that way sometimes. Fortunately, they pay me well for it. Besides, copy & paste is for when you have nothing of your own to contribute. :)
 

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There will always be some variations, as their temperature compensation curve is an approximate. If there are big variations, then worry. Otherwise, just ride it. :)
 
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