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F750GS (/F850GS) low tire pressure indicator?

shalperin

New member
After riding for 10 minutes, I did not see a low pressure warning, but tire pressure was 10lbs low when I finally navigated to the correct screen.

If you are riding down the street and get a slow puncture, its supposed to let you know. I can't figure out why mine didn't warn me.

Is there some setting?
 
Maybe one of those “pictographic” screen symbols? There may be an explanation of what you were supposed to see? I would expect to see the warning on the main screen.
OM
 
I'm going to do a little experiment and see if I can catch it in the act. When it's nicer out I'll set the tire pressure to 10lbs under and ride around a bit locally on slower roads. I'd like to see that the tire pressure reading does show the correct (or temperature adjusted per the manual) reading, and that the automatic warning goes off. I'll see if I can catch it on camera misbehaving. 10lbs under isn't going to kill me, esp. at 35 mph.
 
I'm going to do a little experiment and see if I can catch it in the act. When it's nicer out I'll set the tire pressure to 10lbs under and ride around a bit locally on slower roads. I'd like to see that the tire pressure reading does show the correct (or temperature adjusted per the manual) reading, and that the automatic warning goes off. I'll see if I can catch it on camera misbehaving. 10lbs under isn't going to kill me, esp. at 35 mph.

With all respect due, my $50 aftermarket TPMS beeps and flashes quite annoyingly if the pressure gets 10% (not 10 p.s.i.) low.
 
I don't know what the threshold is, but the one time I got a really bad puncture the light came on in the time it took me to pull over. I heard the puncture and knew what happened and immediately started slowing to pull over, so maybe 10s to flat and 5s for the light to come on yellow (warning, pressure low) and then another second to red (pull over before you die). The other time it was a slow leak when I parked the bike. When I started up and tried to ride away the warning light came on immediately once the sensors initialized. I didn't even make it out of the parking lot and the pressure was reading about 15psi.
 
There is some information about the tire pressure warnings in the F750GS Owner's Manual chapter STATUS INDICATORS.

On my F700GS it looks about the same as for the F750GS. If the tire pressure is close to the permissible tolerance range, the triangle general warning light comes on showing yellow. If the tire pressure is outside the permissible tolerance the warning light flashes red.

Unfortunately the Owner's Manual does not state what the psi ranges are for permissible and outside permissible.

It happened to me when riding one day I picked up a tiny nail. When the yellow light came on I changed the display to show the readings from the TPM: 30:32, so ~30 PSI front, ~32 rear. Twenty minutes the light was flashing red and the TPM showed ~30:~25. I don't remember the exact numbers.

Did you get the 10lbs low from the display or by using a manual tire pressure gauge?

Keep in mind that the tire pressure shown by a manual tire pressure gauge only matches the tire pressure of the TPM when at sea level and at 20 degrees Celsius. But that is a totally different story.
 
Unfortunately the Owner's Manual does not state what the psi ranges are for permissible and outside permissible.

.

My bike and car manuals also do not show that figure.
We've had TPM in our cars since 2008 that show the tire pressure figure and on our bikes since 2011 and have never seen a low pressure warning.
I have no idea at what tire pressure a warning is displayed.
 
I checked the tire pressure in the "info status line", and read 10 pounds under, both tires.

Also checked with a meter to confirm when I got off.

Ambient temp was probably 48, and I understand that there is some temperature compensation in the on-board display, but probably not that much.

I think it's 100% possible I just didn't see the dummy light, which is why I want to do the experiment above.

I have software version 022_005_041, but haven't heard of anyone else having similar issues.

There _is_ also a setting to control wether to show RDC warnings, but I believe this was toggled to on, or at least I hadn't changed it since new.
 
Also checked with a meter to confirm when I got off.

Ambient temp was probably 48, and I understand that there is some temperature compensation in the on-board display, but probably not that much.

.

At 48 F your tire gauge will vary about 1 psi on the front tire and 2 psi when comparing to the dash reading.

I use this chart when when airing our tires in the garage and using a tire gauge.
Tire Pressure.jpg
 
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