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The tires do maintain pressures much better and the tire pressure sensor was not on even on the coldest mornings.
From my personal experience, I just don't follow the "maintains presssure better".

Except for the 35+ year old pickup I had with rusty rims, I don't remember ever having a vehicle where I had to adjust the air more than twice a year.
OK, well maybe that VW bus I had but almost everything on it had to be "adjusted" daily !!

While there might be some TINY advantages, the biggest one is allowing the dealers to take more $$$ out of your wallet !!
 

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From my personal experience, I just don't follow the "maintains presssure better".
I keep a close check on my tire pressures. With the moisture in your tire, the pressures can vary with temperature. Then as the tires heat up and cool down as driven, the pressures will vary. That is why in the winter, my tire pressure sensors will be blinking (20% low) and so I would have to drive the car until the tires warmed up enough to bring up the pressures so that the sensors would go off. With the nitrogen in the tires, I have never had that happen even on the coldest mornings. I have no idea as to how much the nitrogen machine costs, so, I have no idea as to how much it costs to recover the cost and make some profit for the dealer or shop.
 

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With the moisture in your tire, the pressures can vary with temperature.
The pressures WILL vary some with temperature; they will vary MORE with moisture too.

So, what's to prevent the "dealers" from running an air dryer and calling the resulting product "dry nitrogen"? It is, as was mentioned earlier, about 70% nitrogen to start with !! :roll: :mrgreen:
 

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The pressures WILL vary some with temperature; they will vary MORE with moisture too.

So, what's to prevent the "dealers" from running an air dryer and calling the resulting product "dry nitrogen"? It is, as was mentioned earlier, about 70% nitrogen to start with !! :roll: :mrgreen:
I don't know. The dealership I worked at had a nitrogen machine. It looked like a regular air compressor with extra hoses. I did learn how to run it so I could fill up my tires with it. I had to empty out the...glass thing that captured the moisture (don't know the official name for it). I was always surprised as to how much water would be in it from one fill cycle. But, as for the other shops, you are right. There is no way to know for sure if they are using a "nitrogen compressor". Or if they are even maintaining it and operating it properly.
 

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I don't know. The dealership I worked at had a nitrogen machine. It looked like a regular air compressor with extra hoses.
Well, yes, that kind of WAS my point.

Actually seperating air into it's various component gasses is NOT a simple process and happens at the liquid level; extreme temperatures and extreme pressure.

I think what you are actually getting is VERY dry AIR.....at your shop or any other....unless they buy dry nitrogen in pressurized bottles. I've heard that race teams that are serious about tenths of a pound of pressure do exactly that.

:bluethum:
 

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Doesn't justify the money spent for me though. I worked in a Car audio/Custom wheel & tire shop for over a year and have never seen a problem with moisture with the 100+ sets of wheels and tires changed. It sounds cool though.
 

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We've had this debate a hundred times, and I'm still waiting for someone to explain the hypothesis (doesn't qualify as a theory) that water vapor acts differently than the other gasses in the tire. Google "ideal gas law".

Waiting....

;-)
 

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and I'm still waiting for someone to explain the hypothesis (doesn't qualify as a theory) that water vapor acts differently than the other gasses in the tire.
Well, your wait is OVER !!! :mrgreen:

IF the water stayed as a vapor 100% of the time, it wouldn't be that much different than the other components of the air.........however.........

The big difference comes mostly from water condensation, that is, changing from liquid to gas. Look up the volume difference between 1 measure of liquid water versus the same measure (by weight) of water vapor.....and I think it is pretty easy to see that the change of state in a confined space could (and does) make a BIG difference in pressure.

:bluethum:
 

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I guess it didn't occur to me that it would liquefy, nor that even that much would make a difference. Thanks.
 

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Not sure it is relevant but the service manager at the local dealer told me to run 41psi in the rear and 36psi in the front for the Dunlop Qualifiers on mine. It seems to work fine as far as I can tell. Not really impressed with the Dunlops though. Moderately sticky but the mileage blows.
 

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Not sure it is relevant but the service manager at the local dealer told me to run 41psi in the rear and 36psi in the front for the Dunlop Qualifiers on mine. It seems to work fine as far as I can tell. Not really impressed with the Dunlops though. Moderately sticky but the mileage blows.
Not relevant to what ??
It certainly is relevant to WEAR.
Over-inflation will cause increased WEAR and a harsher ride.
It pounds the rider AND the suspension harder.

What exactly was his justification for the higher pressures......except for selling more tires ???

At many dealerships, the service manager monkeys are not even qualified mechanics.

You just can't go wrong by following the recommendations in the manual........unless maybe you do something strange with really exotic tires.
 

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Not relevant to what ??
It certainly is relevant to WEAR.
Over-inflation will cause increased WEAR and a harsher ride.
It pounds the rider AND the suspension harder.

What exactly was his justification for the higher pressures......except for selling more tires ???

At many dealerships, the service manager monkeys are not even qualified mechanics.

You just can't go wrong by following the recommendations in the manual........unless maybe you do something strange with really exotic tires.
I am not sure that those pressures are wrong. My Gixxer and the Super Hawk requires 42 in the rear and 36 in the front.

Just looked it up. Suzuki recommends 42 rear and 36 front.
 

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I've also heard from ST riders that a few extra pounds helps with wear. I'm running a couple psi high since my new commute involves 32 miles each way of a road you could fire a bullet down. Talk about superslab drone. At least I get to ride. I'm coming up on a thousand miles of commuting in three weeks.
 

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Not relevant to what ??
It certainly is relevant to WEAR.
Over-inflation will cause increased WEAR and a harsher ride.
It pounds the rider AND the suspension harder.

What exactly was his justification for the higher pressures......except for selling more tires ???

At many dealerships, the service manager monkeys are not even qualified mechanics.

You just can't go wrong by following the recommendations in the manual........unless maybe you do something strange with really exotic tires.
Let me clarify... I'm not sure if it's relevant to the conversation anymore since the thread has kinda took a turn. Of course tire pressure is relevant but the conversation has gotten turned around a bit.
 

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I've also heard from ST riders that a few extra pounds helps with wear.

At least I get to ride. I'm coming up on a thousand miles of commuting in three weeks.

That very well could be true......but just doesn't sound logical to me....because it would tend to make the contact patch smaller, right ??

Enjoy your riding commute while it lasts. WINTER is coming! :sad:
 

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OK, so what was the point of mentioning it then ?????
Phil......?????
Color me confused. :???:
I think he mentioned it because he was not sure the pressures were good. Your response made it sound like it was a little high. I just responded That they seemed correct. Just trying to help.
 

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That very well could be true......but just doesn't sound logical to me....because it would tend to make the contact patch smaller, right ??

Enjoy your riding commute while it lasts. WINTER is coming! :sad:
My thoughts exactly. Maybe it has to do with reduced carcass flex.

Wiinter coming? It hasn't left! We've had a strange cool snap the last week or so the likes of which we haven't seen since the 1950's.
 

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I just responded That they seemed correct. Just trying to help.
Maybe that WAS the response he was looking for.

I ASSumed that he thought something was amiss with the recommendation.
I further ASSumed that he knew his bike and if HE thought the numbers were wrong, they probably ARE.

Guess all that just makes me an ASS !! :shock: :lol4:
 

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Maybe that WAS the response he was looking for.

I ASSumed that he thought something was amiss with the recommendation.
I further ASSumed that he knew his bike and if HE thought the number were wrong, they probably ARE.

Guess all that just makes me an ASS !! :shock: :lol4:
:lol4: All is good. We all do it from time to time.
 
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