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Tire Pressure

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Interesting, I‘m going to give this a try. My B rides great already but for longer trips this might make it even better.
 
On my TC, if the tire pressures are above or below spec by more than 0.1 psi I get the tire exclamation point. The bike wants the pressure to be spot on the spec prescribed for it. The problem is that tire pressures can change by 3 psi easily on a highway run.
 
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Theoretically, the bike should be compensating and displaying an adjusted pressures.
I haven't had the TC long enough to comment on the fluctuations of what is displayed on the TFT.
But I have not seen a warning come up yet and the ambient temp has been going up and down 40 degrees F.
 
Pour Le pneu arrière de R18 TC:
sur la notice : 46 PSI ( 3,2 BAR)
sur la moto : 45 PSI ( 3,1 BAR)

Mais sur le pneu Michelin, le maximum : 42 PSI ( 2,9 BAR) !!

QUELLE EST LA BONNE PRESSION ?
 
Gentlemen... and ladies of course! I recall having read that tires come from factory filled with Nitrogen gas. Can anyone please confirm this?
 
I never heard this but am quite curious. What is the benefit of nitrogen if air is 79% nitrogen anyway?

FYI.......I really like the real time data available on the R18B/TC while riding, especially the tire pressures.
 
R12C-R18TC said:
I never heard this but am quite curious. What is the benefit of nitrogen if air is 79% nitrogen anyway?

FYI.......I really like the real time data available on the R18B/TC while riding, especially the tire pressures.
Click to expand...

There are some minor/negligible benefits to nitrogen such as keeping the inside of the tire moisture free which will supposedly:
-Help with longevity of tires/wheels and
-provide more consistent increase and decrease of tire pressure caused by expanding and contracting due to temperature.

None of these are even remotely significant enough to pay for or be hassled by nitrogen filling imho, I've been running an auto repair shop for nearly 15 years. But don't listen to me. Listen to these top three tire companies. Well, I suppose you can say they have their biases too...

-From Continental's website
"So, now we come to the big question: is nitrogen right for your tires? The fact of the matter is that inflating tires with nitrogen is not necessary for typical everyday use on a passenger car. It might even be considered a frivolous waste of money.

To be clear, inflating tires with nitrogen is not harmful. Moreover, the PSI stays steady in the long term. (Tires filled with regular air lose pressure through permeation a little more quickly.)

But for the most part, nitrogen makes absolutely no difference when it comes to a loss of pressure caused by tire punctures, tire bead leaks, valve leaks, or other mechanical leaks. There’s no discernible benefit over air-filled tires, and that includes performance factors such as rolling resistance, fuel economy, and tire aging."

-From Michelin's website
"Nitrogen and compressed air CAN be mixed, if needed. Tires manufactured by Michelin are designed to deliver their expected performance when inflated with air or nitrogen, as long as the user respects the pressures recommended by the vehicle manufacturer on the vehicle’s placard or by the tire manufacturer."

-From Bridgestone's website
"Nitrogen is an acceptable inflation gas for use in Bridgestone and Firestone passenger, light truck, and truck tires. Bridgestone has no comment on the various performance claims made by Nitrogen suppliers."
"Nitrogen molecules are larger than oxygen molecules, which means nitrogen escapes more slowly through the inner liner membrane used to retain air. The process of air escaping is known as permeability. This can mean tires maintain their correct pressure longer with nitrogen. Nitrogen's dryness makes it more stable than standard compressed air. In contrast, the compressed air in your tires contains water vapor. This water vapor might promote corrosion in some wheels (and tire pressure monitoring systems (TPMS) if your vehicle is equipped with one), and water vapor pressure fluctuates with temperature changes. This means tire pressures may vary more as ambient temperatures rise and fall than they would with nitrogen-filled tires."
"There’s nothing wrong with keeping your tires inflated with air. It’s been used for over a century by motorists around the world. Compressed air is easy to find and often free – critical factors for many drivers concerned about maintaining their tires’ pressure."

I hope that helps...
If the shop is putting in nitrogen for free, I wouldn't say no but I would not pay for it on a street bike.
 
We put nitrogen in Aircraft (heavy commercial ACFT) tires for the simple reason it does not expand or contract with heat. i.e. increase or decrease pressure. I initially thought it was a bunch of "hooey" when they started putting it in auto tires, but I have to say the the tire pressure change I use to get when the weather turned colder / hotter has gone away! Pressure also seems to remain constant as well. I am contemplating doing my RV trailer tires and even my R18 TC. Just need to find a tire shop in my area that can do it. The other reason its in aircraft tires it is an inert gas. Not really applicable in this situation.
 
I’m not doubting the truth of your statement but pressure, volume, and temp for any gas behave according to the gas law. Volume and Pressure are proportional to Kelvin Temperature.
The air we breathe is 79% nitrogen anyway. I still don’t get the nitrogen notion.
 
Nitrogen most certainly makes a difference. Every factory motocross team, nascar, etc use nitrogen. Military application as well as mentioned above. Helium would be the absolute best but the molecules are so small it would pass through the tires
 
For the purists are you purging to achieve the removal of the remaining % that causes the fluctuation in pressure? The small amount of deviations from "perfect" pressures for a "non-racing" application and certainly the variables and demands on aircraft are more a fun exercise than anything tangible to mere mortals concerning the tire applications on touring motorcycles. On countless trips I have experienced several LBS difference in day to day cold morning temps (30-40*f some days v. 70*f+ others) and within very few miles the TPM showed all was "normal" and as long as it was a relatively close change in both tires I never messed with adding air or having to release air for such short durations, it's silly. The same for short durations involving huge elevation changes. YRMV and everyone should do what gives them the most confidence, etc., etc. I've had some tires that never needing air added, but most lost 1-2 LBS a month with a few needing a closer eye on them, but AFAIK none were inflated with anything other than Standard Issue Air.

Ride more, worry less 🍻 🍻 🍻
 
Over here in Kansas we had a morning temp of 26F about 2 weeks ago. I rode the R18 and noted the tire pressures. Next day we hit 82F in the afternoon and I rode again. Whoa....what a difference 60 degrees makes in tire pressure. For small volume tires (compared to a car) the effect is remarkable.
 
Tires and their inflated pressures are EVERYTHING....Makes a huge difference in how the bike handles. I follow the manuals spec very closely.
 
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