RDC values?

[snerkler]

Since I picked my bike up a couple weeks ago my tyre pressure monitor has been reading the pressures as slightly high (2.6 and 3.1bar) and I just assumed the dealership had overinflated them. Yesterday I checked them myself (cold tyres) and both of my gauges said 2.5 and 2.9 bar respectively. Out riding today the bike's still saying 2.6 and 3.1bar.

According to the manual the RDC is supposed to be temperature compensated so why it is reading high? It would seem odd that that's accurate yet 3 gauges (dealership + two of my own) are wrong is there a way to calibrate the RDC?

 

[Bigcats]

I believe it can be done via a GS-911

Obviously the dealer can also do it (probably far cheaper than buying a GS-911 just for this)

Or if you are lucky someone may be local to you and a couple of shandies they may do it for you using a GS-911

But your device may not be calibrated to what the dealer uses hence the slight difference, I use a dewalt device and like yours reads slighting lower than what the bike states but I now know if I do it via the air inflator its correct

 

[stever1]

Remember that a hot tyre will give a higher reading. On my wing it climbs by about .3-.4 of a bar when hot.

 

[leadfarmer]

They can go up a couple of tenths when hot, it's normal

As long as you set them cold as you are doing it's fine

 

[snerkler]

Remember that a hot tyre will give a higher reading. On my wing it climbs by about .3-.4 of a bar when hot.

They can go up a couple of tenths when hot, it's normal

As long as you set them cold as you are doing it's fine

Thanks, good to know. I did think that, but the manual says that it’s compensated for temperature so it got me questioning it

 

[wessie]

the TPMS is compensated for an ambient temperature of 20C (if I remember correctly). Therefore, if you set the cold temperatures at 15C ambient the ECU will show a higher value.
I took a ride yesterday, during the ride the ambient temperature varied by about 10C as at one point I was riding in the Welsh Hills at 13C and then 23C in the Severn valley near home. Worrying about a few tenths of a bar seems pretty pointless to me.
If you really want to calibrate the TPMS, you need to do it at the nominal ambient temperature.

 

[snerkler]

the TPMS is compensated for an ambient temperature of 20C (if I remember correctly). Therefore, if you set the cold temperatures at 15C ambient the ECU will show a higher value.
I took a ride yesterday, during the ride the ambient temperature varied by about 10C as at one point I was riding in the Welsh Hills at 13C and then 23C in the Severn valley near home. Worrying about a few tenths of a bar seems pretty pointless to me.
If you really want to calibrate the TPMS, you need to do it at the nominal ambient temperature.

I'm not worried about a few tenths, I'm just trying to assertain whether a) the RDC is working correctly, and b) whether I should trust the RDC or the tyre pressure monitor

Straight from the manual:-

"Temperature compensation

Tyre pressure is a temperature sensitive variable: pressure increases as tyre-air temperature rises and decreases as tyre air temperature drops. Tyre air temperature depends on ambient temperature as well as on the style of riding and the duration of the ride.

The tyre-pressure readings in the multifunction display are temperature-compensated and are always referenced to a tyre-air temperature of 20 °C. The air lines available to the public in petrol stations and motorway service areas have gauges that do not compensate for temperature; the reading shown by a gauge of this nature is the temperature dependent tyre-air pressure. As a result, the values displayed there usually do not correspond to the values displayed in the display."

I've read this several times and it's still not clear. If if said air temperature of 20 °C no problem, but it says tyre-air temperature of 20 °C

As I said I'm not worried about it, curiosity just gets the better of me

 

[wessie]

If the bike has cold pressures then the temperature of the tyre air can only be from the ambient conditions surely as cold in this context means parked up for some time? Once you start riding the bike, the tyre will start at ambient and rise depending on other factors such as riding style and the tyre construction.
You seem the be over-thinking things based on a phrase that was probably badly translated from the original German.

I go back to my first post, if you are making comparisons between the TPMS and your gauge at anything other than where the tyres are at an ambient 20C you will not get a valid comparison.

 

[GSADavidZH2]

My 2020 GSA reads the same as yours Snerkler, I bought a new digital gauge, but the results were just the same. Mind you having used the same gauge for over 20 years without any handling issues, I just now ignore it. Mind you, I had 2 tyres fitted before a Spain trip, and the RDC was reading 2.4 and 2.8 respectively.

 

[Cjm2993]

I have seen the rear start from the garage at 42 and climb to 44.5 and I ride genuinely like miss daisy… getting 60mpg with a pillion miss daisy

 

[casbar]

The TPMS is not that accurate, the TPMS is there primarily to warn of a deflation, it is not supposed to be used to check your tyre pressures.