Tire Air Question

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I live in the great Pacific Northwet where the weather varies greatly and humidity can be quite high. For these reasons I change the air in my tires after every ride. Keeps inner rim corrosion at bay and and old air is just so, well uh.......used.
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Besides,you know what they say about fresh air being good for you and all.

I use 40f and 42-44r at every fill up.

 
Forum wisdom seems to see the front tire, regardless of manufacturer doing the best in the 42 psi range and the rear someplace in the 42-44 psi range. This yields the best tire life, tire condition and handling. But please, be sure you are running the correct seasonal air, right now you should be running Spring air and in 6 weeks using Summer air
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I am in Big trouble.

I spent the winter in So. Cal. but now I am back in Boise Id.

Not only am I running the wrong seasonal air, I am using California air.
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40/43 on a new pair of T30's feels pretty good during my short commute. As is gets warmer here in the PNW and I am doing more weekend rides I think I will try dropping the pressure slightly. I have all the traction I need right now but know there roads in the Cascades that demand more of me and the tires.

 
Forum wisdom seems to see the front tire, regardless of manufacturer doing the best in the 42 psi range and the rear someplace in the 42-44 psi range. This yields the best tire life, tire condition and handling. But please, be sure you are running the correct seasonal air, right now you should be running Spring air and in 6 weeks using Summer air
wink.png
laugh.png
I am in Big trouble.

I spent the winter in So. Cal. but now I am back in Boise Id.

Not only am I running the wrong seasonal air, I am using California air.
fool.gif
No, I think you'll be ok. It's when you bring out-of-state air into Calf. that you might get jammed up. Next year you should stop into a state office and get the compliance/exemption sticker.

 
Forum wisdom seems to see the front tire, regardless of manufacturer doing the best in the 42 psi range and the rear someplace in the 42-44 psi range. This yields the best tire life, tire condition and handling. But please, be sure you are running the correct seasonal air, right now you should be running Spring air and in 6 weeks using Summer air
wink.png
laugh.png
I am in Big trouble.

I spent the winter in So. Cal. but now I am back in Boise Id.

Not only am I running the wrong seasonal air, I am using California air.
fool.gif
No, I think you'll be ok. It's when you bring out-of-state air into Calf. that you might get jammed up. Next year you should stop into a state office and get the compliance/exemption sticker.
To be sure, you should check with the California Air Resources Board (CARB) as I hear that they are the ones who set all of the air regulations in CA.

As to the question of whether to use pure using Nitrogen gas in your 36 psi inflated tires, I prefer to use a special mixture of 78% Nitrogen (N2), 21% Oxygen (O2), and 1% Argon (Ar). This super secret proprietary mixture has been proven effective at keeping tires inflated in all sorts of difficult conditions for decades. The best part of it is I can sell it to you much cheaper than that crummy pure Nitrogen Gas stuff.

 
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Be sure to keep industrial air separate from potable air when filling your motorcycle tires, I would hate to see someone get hurt.

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A few years back I put on a fresh set of Battlax 20's and ran them 39/42 as per swingarm spec. I used Canadian air but the trip was 4000 KM thru the US so I don't know if the metric air caused premature wear on imperial roads. I arrived home with terminal cupping on front and mild cups on rear. I am a bit anal about tire pressure and checked/filled every second gas fill. Now running Battlax 23 GT. I run them at 41/43 and they both have over 4500 km and lots of life left.

 
A few years back I put on a fresh set of Battlax 20's and ran them 39/42 as per swingarm spec. I used Canadian air but the trip was 4000 KM thru the US so I don't know if the metric air caused premature wear on imperial roads. I arrived home with terminal cupping on front and mild cups on rear. I am a bit anal about tire pressure and checked/filled every second gas fill. Now running Battlax 23 GT. I run them at 41/43 and they both have over 4500 km and lots of life left.
It is illegal to import Canadian air into the US without a prescription. Give my your address...I'm gonna send the Air Unit to your house with the SWAT team to teach you a lesson.

 
Of course, I'm running the super special Dark Air in my rear tire. It runs best at 30 psi. So far it has got me past 36,000 miles and still going strong.The fresh PR4 GT up front is set to 42.

YMMV

Brodie:rolleyes:
+1 on the Special Dark Air @30-31psi.Same blend & pressure for the FJR and the Wingabago.

Coincidentally, I also use the same oil in both bikes.

(Notice the clever segue from tire pressure to oil? Guaranteed to get this moved from here to NEPRT, even if it is Friday.)

 
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I honestly surprised no-one has mentioned the benefits of Heliox.

I've run 79/21 Helium/Oxygen sourced from a local dive shop for the last 6 years.

When I used to run atmospheric "air", I found the turbulence of this heavy gas inside the tire negatively affected the bikes ability to rapidly lean into corners.

I think the inertia of the forward rolling air mass inside the tire was causing a negative, or "double gyro" effect on the wheels. The Heliox, with its lower turbulence coefficient, has greatly improved my bikes turn-in ability.

I briefly experimented with 100% helium but found a distinct loss of traction at all speeds. I tried adding dyna-beads thinking they would increase the gravitational gyro effect, but the static charge (+/- 0.987 mV) negated what little benefit was gained.

+1 for 39/42

 
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I tested it again today for the fun of it under different road conditions. The bike at high speed 115 plus does feel considerably smoother with 36 front and rear tire. I then put 42 in the rear and 36 in the front. Then road it at the same speeds,. not near as smooth as with 36 and 36. Now I know way the manual says this, interesting!. Realizing tire wear will suffer at lower tire pressures but I have been told that at high speeds tires will generate greater heat increasing the PSI . Must be the reason it was in the manual to use those lower pressures at high speeds.

 
...Must be the reason it was in the manual to use those lower pressures at high speeds.
The tire pressure rating on the swing arm and owners manual were set for the type of tyres, err tires that were OEM when the '05 was new. You can't get those tires today (and shouldn't) and the newer tires may indeed prefer to be run at higher pressure.

  • Higher pressure tires run cooler than lower pressure tires.
  • Higher pressure tires have a better opportunity to last longer and provide better gas mileage.
  • Higher pressure tires will be stiffer and handle better in turns with less sidewall flex.
  • Higher pressure tires will be stiffer and transfer more road surface to the bike.
  • Higher pressure tires will be less compliant on bumps and pot holes.
Measure your tire pressure when cold. Ride long and hard, get off and immediately measure the tire pressure when hot. If the temperature readings are a lot different, increase the tire pressure a couple of pounds and try again on another day. There shouldn't be a large temperature difference between cold and hot. Soft tires get hot and that is why you measure the temperature gain. Temperature gain is a valid method to determine correct inflation.

The rule of thumb is for every 10° Fahrenheit change in air temperature, your tire's inflation pressure will change by about 1 psi. For car tires the pressure varies a bit with road and ambient temperature, but if inflation is correct for the load, contained air temperature probably settles somewhere around 50 to 60 degrees Fahrenheit above ambient. That would equal 5-6ºF increase for a correctly inflated tire.

Holy s#it, where did that come from on a Friday?

 
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Isn't the easy rule of thumb a 10% increase in pressure elevated by heat? So a tire that's 40psi cold should be around 44psi hot. Of course this could depend on changes in ambient temp I guess.

I think I'm gonna a just start filling tires with beer.

 
Isn't the easy rule of thumb a 10% increase in pressure elevated by heat? So a tire that's 40psi cold should be around 44psi hot. Of course this could depend on changes in ambient temp I guess.
I think I'm gonna a just start filling tires with beer.
Yer gonna have a **** ton of flats If I'm around.
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Isn't the easy rule of thumb a 10% increase in pressure elevated by heat? So a tire that's 40psi cold should be around 44psi hot. Of course this could depend on changes in ambient temp I guess...
I cut the AZ rider some ambient slack and went with ~12% to accommodate 115º ambient with 170º pavement. In the 'east of the Mississippi' part of the country where it's the humidity and not the searing sun, 10% is a good number.

Even the British won't like the hot beer from the tires, though in a pinch, alcohol is alcohol. I'm thinking heated, flaming vodka shots
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I always check tires cold. the other information is good to be reminded of. I also went through three gauges that gave me all different PSI readings before I bought a new one. And that is the one I am using. It is an interesting note that the manual recommends those lower Pressure at high speed. Their most be a reason. Why!

 
...It is an interesting note that the manual recommends those lower Pressure at high speed. Their most be a reason. Why!
The owners manual lists the same pressure for both normal use and high speed use. That pressure rating was true for the OEM tires 9 years ago. Today's tires are not yesterday's tires. I suspect that the tire pressure specification 9 years ago was probably low. Note that there are errors in all Yamaha manuals. Read the shift points in the same owners manual and live by them under all situations. You may find that it doesn't work so well.

 
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