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ahh-cool
04-12-2015, 07:57 PM
I ordered the FOBO for the Spyder and since I have my bike taken apart I put it on my car.
First let me say it works completely as advertised.
The problem I have is, I never realized what happens to tires when you're rolling down the hot pavement.
My car tires are suppose to be aired up to 30PSI and I always put in 32.
I need to apologize to my tires for stressing them out that much.
At 32 PSI it will rise to about 37 PSI and the temp would start at 88 F and go to as high as 116.
At 30 PSI it will rise to about 33 and the temp will go to as high as 95 F.
I always thought it would rise a pound or so, never gave much thought to the heat.
All I can say is I'm amazed at my findings.
Stefan

IdahoMtnSpyder
04-12-2015, 09:15 PM
I ordered the FOBO for the Spyder and since I have my bike taken apart I put it on my car.
First let me say it works completely as advertised.
The problem I have is, I never realized what happens to tires when you're rolling down the hot pavement.
My car tires are suppose to be aired up to 30PSI and I always put in 32.
I need to apologize to my tires for stressing them out that much.
At 32 PSI it will rise to about 37 PSI and the temp would start at 88 F and go to as high as 116.
At 30 PSI it will rise to about 33 and the temp will go to as high as 95 F.
I always thought it would rise a pound or so, never gave much thought to the heat.
All I can say is I'm amazed at my findings.
Stefan
How evenly are they wearing? If evenly then keep with the 32 psi. You can rest assured that tire engineers have know for decades how to design for the increased pressure caused by rolling friction heat and for a margin above and below the recommended max cold pressure.

SPECTACUALR SPIDERMAN
04-13-2015, 08:00 AM
if you are worried about psi variance i would recommend you use nitrogen in them as i do, next use a good
pressure gauge to verify the sensors are accurate

ahh-cool
04-16-2015, 08:44 PM
I use a mix of 80% N2

bzbaeren
04-16-2015, 09:24 PM
I use a mix of 80% N2
So you use air?:yes::yes:

jwulf74
04-17-2015, 11:22 AM
I use a mix of 80% N2

Me too...the mechanic always looks at me funny when he asks if I want it and I say "sure, but put in the 80%". The wife rolls her eyes, but I always get a kick out of it. :D

pauly1
04-17-2015, 12:34 PM
So...the claim with N2 is that is tires hold pressure better. That would imply that the other gases leak out more easily, passing through the pores in the tire carcass. So if I pressure up with good ol' 80% N2 containing air, and the none-N2 gases leak out preferentially, then at some point I would have a >95% N2 content in my tires. Right?

Wayne

aeroshots
04-17-2015, 12:36 PM
So...the claim with N2 is that is tires hold pressure better. That would imply that the other gases leak out more easily, passing through the pores in the tire carcass. So if I pressure up with good ol' 80% N2 containing air, and the none-N2 gases leak out preferentially, then at some point I would have a >95% N2 content in my tires. Right?

Wayne

Interesting:dontknow:
I like the way you think.:thumbup:

finless
04-17-2015, 12:43 PM
I thought the idea of using N2 was two fold

1) It does not deteriorate rubber like plain air can over time (e.g. no Ozone or other gasses).
2) The pressure change is not as dramatic as the temperature of the tire changes.

That's my understanding anyway.

Bob

ahh-cool
04-21-2015, 11:13 PM
They tell you that the reason that you are suppose to use nitrogen is because they use it in airplanes.
As an ex-aircraft inspector, I will tell you that is true.
The reason we used N2 in airplanes is because it's dry. when the airplane comes down from -75 deg you will not have ice in the tire.
Not because it's better. We use N2 in small general aviation also because it's convenient. it's easier to carry a bottle of N2 around then an air compressor.
Stefan