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Are the TPMS over sensitive on the new wings? I filled up my tires at 70f unridden in my garage. The front at 37 lbs and when I go to ride the bike in 60f weather the light is on saying that it only has 32 lbs.
 

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yea, i dont know how accurate they are. i use a good gauge and use the tpms to give me an idea as whats going on at any moment
 

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One of the requirements of the TREAD act passed by Congress in 2000 was the TPMS system gives a warning when the ignition is turned on if a tire/tires were under inflated by 25% or more. I don't know if the wing's sensors are set up the same way.

The recommended front tire pressure for the wing is 36 psi. 25% of 36 is 9 so the TPMS warning light would come on at 27 psi if the sensors are set up the same as for a motor vehicle under 10,000 GVW. The Fed document is FMVSS 138.

:doorag:
 

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The TPMS used to bug me.

I'd leave the house at 38 ids on a 80 deg. day and the temperature would spike to 90 - 95 deg. And the TPMS would show tire presure at 45 lbs. an hour later I hit a small rain shower and the TPMS dropped to 30 lbs.

Just the nature of the beast, I guess.

Greg
 

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The TPMS used to bug me.

I'd leave the house at 38 ids on a 80 deg. day and the temperature would spike to 90 - 95 deg. And the TPMS would show tire presure at 45 lbs. an hour later I hit a small rain shower and the TPMS dropped to 30 lbs.

Just the nature of the beast, I guess.

Greg

That is the cool thing about the sensors on my GSA, and I can't explain it exactly but they show the pressure based on normal ambient temperature, not what the pressure is due to heating while you ride.
 

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I have had my TPMS light on my 2018 start flashing at 32 or 33 psi for the front. Once the tire warmed up, and it got to 34 psi the light went out. As far as I can tell, there is no specific explanation for what the triggers are for the system either in the owners manual or shop manual.

However, in the shop manual I found diagnostic tests related to 10% and 20% of suggested pressures. So, if we assume 10% is the first warning, then for the front the light would flash when we were down 3.6 psi (36 psi * .10), or down to a pressure of 32.4 psi. That corresponds to what I have experienced. I have also found that the TPMS on the bike reads at least 1 psi lower than my tire gauge.

So...... with the smaller volume of the front tire and the TPMS being a little pessimistic, it does not take much below 36 psi on the front and a quick shift from hot one day to a cold front the next to get the flashing TPMS light 1/4 or so after you take off. At least the 2018+ shows you the actual pressure along with the light, unlike the 2009-2017s where you get the light but have no idea of which tire and how low you actually are.
 

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That is the cool thing about the sensors on my GSA, and I can't explain it exactly but they show the pressure based on normal ambient temperature, not what the pressure is due to heating while you ride.
id want the reading to be what the tire is experiencing, not what the ambient temp is...in other words, i want to see the reading when im double up on 100 degree day in the desert...no?
 

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I "think" the temperature of the asphalt or concrete is what builds the pressure in the tires. The only time I will adjust the preasure when I'm on a ride is below 32 and above 44 PSI.

Not sure that is necessary, but that's just me..

Greg
 

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Ive seen my rear tire hit 50 psi with the scenario I described. I just leave it. i dont reduce it. Im thinking it should be able to handle that
 

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id want the reading to be what the tire is experiencing, not what the ambient temp is...in other words, i want to see the reading when im double up on 100 degree day in the desert...no?

That was my first thought to, but think about it this way; you get a slow leak and on the Wing with the PSI showing 50 it starts to SLOWLY trend down, it will take even longer for you to know that you have a leak vs the tire cooling off (I'm thinking). Whereas if the tire pressure is temperature corrected to 42 even though it it blazing hot outside. , you will suspect something is wrong if you see it drop to 40 psi. If it dropped on the wing from 50 to 48, I wouldn't be certain that it is a slow leak or the tire cooling off (say going slower).


I'm not an expert on it, just my thoughts and after riding both bikes, I like the correct temperature pressure on the GSA.
 

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Yes the TMPS is over sensitive, after a while you just get used to the flashing yellow light daily in the morning in cooler temps, after a few miles the tires heat up and it goes away. This is one area where BMW Motorcycles give you a lot more leeway, my BMW shows similar temp differences in cooler mornings but it doesn't flash a warning just because the pressure is off a few PSI.

-Jim
 

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Discussion Starter #12
Yes the TMPS is over sensitive, after a while you just get used to the flashing yellow light daily in the morning in cooler temps, after a few miles the tires heat up and it goes away. This is one area where BMW Motorcycles give you a lot more leeway, my BMW shows similar temp differences in cooler mornings but it doesn't flash a warning just because the pressure is off a few PSI.

-Jim
Since I am also coming from BMWs I thought that I would ask the question. The BMW TPMS takes account of the temperature and adjusts so you don't get as many false readings.
 

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I "think" the temperature of the asphalt or concrete is what builds the pressure in the tires. The only time I will adjust the preasure when I'm on a ride is below 32 and above 44 PSI.

Not sure that is necessary, but that's just me..

Greg
Tire and tire sidewall flexing while rolling is the primary factor that causes the tire pressure to increase.

:doorag:
 

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Per Honda the tire pressure needs to be within 2-3lbs of 36/41 after they make adjustments for current outside conditions, and any low psi condition warrants a warring.

On hot days I've seen a difference between a garage value set at 36/41 at 75F in the garage go to 45/50 displayed when highway riding at 105F going into Las Vegas. In cold temps with outside air temps in the low 20's I've seen a garage setting of 36/41 at 50F in the garage go to 31/36 once the bike is outside starting out.

Just how the system works.

-Jim
 

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Tire and tire sidewall flexing while rolling is the primary factor that causes the tire pressure to increase.

:doorag:

What if you have the same friction on a 40 deg. stretch of highway compaired to a 100 deg. stretch of asphalt?
 

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There should also be a tire temp reading as well as the pressure. All of my aftermarket TPMS systems give both. This way, I can tell I may have a leak in the tire when I only have about 43psi but the temp in the tire is 110 degrees. Seeing both will tell me that I have a leak and to check it out. But being warned at mid to low 30's, hot or not is much better than no warning at all other than "why is this thing feeling weird?". I put the same system on my Tailwind as I did on the Boulevard. It is nice to see the correlation of increase in psi and temp. Looking at the bike tires, I had to catch it early before I got a ways down the road or just assume "all was well" because a warmer tire was already bumping up the reading and I had no clue by how much.


My highest temperature I got on trailer tire temp was 120F. That gave me an extra 5lbs in each tire (4.80X12). I have seen as much as 180F on my rear Suzuki M50 tire, but I don't remember the pressure above the sidewall desired 41. The front is usualy about 20F lower than the rear when hot.
 

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I wish it only showed the tire pressure, that’s it!! I don’t need a low (pre-set number) to make an icon flash on the dash! My low 33 psi RF means the damned icon NEVER stops flashing!! What a PITA . . . :cus:
 
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