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Discussion Starter · #1 ·
In previous threads there have been some comments on tire / tyre pressures. (sorry about different spelling but US Tire and UK Tyre forum searches get different results.)
42PSI cold Front and Rear is the recommended norm which seems to be what most people agree with.

My sensor gauge reads 40PSI on first coming on after a few minutes riding. This increases as the tyre / tire warms up to about 42-43PSI.
My question is do we hold at 42PSI on the gauge when the tyre is warmed up or start at a cold reading of 42PSI which to my recconing will increase to 44-45PSI, when the tyres warm up, which seems a bit too high to me.
 

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Chris,

You answered it yourself when you said... 42psi cold! And yes the air will expand to 44-45 when warmed up, depending on how warm the ambient air is and road temperatures. All tire pressures are rated cold i believe.


Jerry
 

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In previous threads there have been some comments on tire / tyre pressures. (sorry about different spelling but US Tire and UK Tyre forum searches get different results.)
42PSI cold Front and Rear is the recommended norm which seems to be what most people agree with.

My sensor gauge reads 40PSI on first coming on after a few minutes riding. This increases as the tyre / tire warms up to about 42-43PSI.
My question is do we hold at 42PSI on the gauge when the tyre is warmed up or start at a cold reading of 42PSI which to my recconing will increase to 44-45PSI, when the tyres warm up, which seems a bit too high to me.
It is my understanding that the tire pressure should be 42 pounds at 65 degrees and if you are riding in very hot weather that pressure might go up as high as 53 to 55 psi but the tire pressure reading would still show 42 psi because the sensor calculated the heat in the process and allows for that; so, in a nutshell, just put 42 psi and you'll be fine.
 

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Well because

Well because we are in metric measurements down in Australia my gauge indicates 290kilo pascals??? What the heck is that? I still work in PSI for tyre (tire) pressures. Some air guns still have both here so ofcourse I worked it out to be 42psi or there abouts. I found 39psi was better for the terrible pot holed roads we have to endure in my state of New South Wales. :runaway
 

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Discussion Starter · #5 ·
Thanks all. I've done some experimenting and find 42psi cold is the best setting. The bike is very sensitive to tire pressures and even a drop of 2psi when cold can have a marked effect on steering and cornering feel. So I say keep your pressures to 42psi front and rear. It's not often that bike manufactures get the pressure specs right but as they tested the bike on the 021's from scratch this appears the best setting for this bike.
 

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I came out of my workshop the other day and hit the sensor , it said 42 psi , front and rear ! I then took off to the main highway and hit it again , ( about 3 klm's from home ) and the rear had gone up to 44 psi , the front had gone up to 43 . I then checked again after about 50 klm's and they hadnt changed . Would it be normal to only change 1 or 2 points after 50 klm's ?
cheers Holma .
 

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I leave my tire display up on the panel all the time. This is consistent with what my tire sensors do... Depending on road temperature mine "grow" 1 to 2 psi.. unless you're working the tires fairly hard in the corners or braking.. then sometimes 3psi.

Jerry
 

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The tyre pressure indicator uses a form of fuzzy logic, whereby it attempts to take into account the type temperature to show a "cold" corrected tyre pressure. Hence after a ride even if the onboard sensor say's 43PSI it will be higher if measured with an external gauge.

I agree about the tyres being sensitive, especially the front, mine was down 2 psi and it felt as if the wheel was trying to tuck under cornering, not bad but just enough for me to know it was time to get the pump out.
 

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Discussion Starter · #9 ·
I agree about the tyres being sensitive, especially the front, mine was down 2 psi and it felt as if the wheel was trying to tuck under cornering, not bad but just enough for me to know it was time to get the pump out.
Exactly right Ian, I have never know a bike with a front tyre so sensative to the pressures. Just a very small adjustment makes the world of difference.
I did notice though, when the tyres were down to around 39 / 40psi especially on hot days (18C plus..Yes thats HOT here chaps) the tyre pressure rose up to 44 / 45psi. It was noticeable that the handling improved dramartically when the sensor read 42 / 43 and up.

Most days at the moment even during hard riding the sensor starts at 42psi and risess only up to 43psi as the road surace temp is quite low.
I too leave my display on sensor temp.
 

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The tyre pressure indicator uses a form of fuzzy logic, whereby it attempts to take into account the type temperature to show a "cold" corrected tyre pressure. Hence after a ride even if the onboard sensor say's 43PSI it will be higher if measured with an external gauge.

I agree about the tyres being sensitive, especially the front, mine was down 2 psi and it felt as if the wheel was trying to tuck under cornering, not bad but just enough for me to know it was time to get the pump out.
If it is the case that it compensates for increasing tyre temperature, why does the pressure display always go up in line with tyre temp? My understanding was the display showed current pressures therefore you should look for 42psi as soon as you're rolling expecting it to increase to 44/45 as things hot up.
 

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Discussion Starter · #11 ·
Garry, I think you are rght there. That was my understanding anyway. I have adjusted my pressures to show 42psi on start up when cold. They then rise to a pressure comensurate with the road temperature and to some extent how hard you ride. The tyre cools quite quickly anyway even after only a short break. But so long as it doesn't get below 42psi I'm a happy bunny.
 

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Also remember that altitude plays an important role in your tyre pressure. We've all found an empty plastic bottle closed in a plane at cruising altitude all crushed after landing!!
 

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it wanders because the logic is not perfect, so it can only estimate tyre temp thus pressure difference.

It's described a bit in the paragraph below, which I got from the acrobat document at the following link :-

http://www.antee.cz/kawasaki/file.php?nid=3819&oid=673295

Tyre Pressure Monitoring System (TPMS)
To warn riders of any tyre pressure irregularities, tyre pressure sensors are fitted as standard equipment (a first for a motorcycle).
The system allows the rider to monitor tyre pressure while underway. When the tyre pressure falls below a pre-defined limit, a low pressure warning is displayed.
The ability to take into account temperature changes and display values recalculated for 20oC helps prevent false warnings when air expands as the tyres warm up.
 

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Well because we are in metric measurements down in Australia my gauge indicates 290kilo pascals??? What the heck is that? I still work in PSI for tyre (tire) pressures. Some air guns still have both here so ofcourse I worked it out to be 42psi or there abouts. I found 39psi was better for the terrible pot holed roads we have to endure in my state of New South Wales. :runaway
Hi Chez, 290 kPa is the same as 2.9 bar (2.9 *14.7psi = 42,6psi)
 

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It's been a while since I looked at the Owner's Manual but can't you select what units are displayed? I know that my display is in PSI.
 
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