Reifen Druck Control

[Pyrrho]

RDC units are known outside Germany as TPMS. Question for those with OEM version... can you change the preferred tire pressure? Maybe with a GS-911 or Motoscan?

[Lee]

I have not heard of anyone being able to do it.

[Ray]

I have not heard of anyone being able to do it.

I haven't heard of anyone who's tried.

The repair manual refers to programming the RDC. The shop computers have more functionality than a 911 - you might check with the guys at the shop to see if it can be done. I'd be surprised if the capability wasn't there.

That said, other than running the RS as a sport bike with different suspension and tires, not clear why the programmed range of pressures would not include pressures you want to run. And if you're going to run special tires and suspension, why would you mess with a stock, temperature compensated monitor that might not be that accurate for tires that require high operating temperatures?

[Pyrrho]

That said, other than running the RS as a sport bike with different suspension and tires, not clear why the programmed range of pressures would not include pressures you want to run.

if I liked to run my tires a pound or two more or less than BMW's recommended values, my preferred pressure may still fall within what BMW has programmed as within tolerance but may be closer to a higher or lower bound. This would possibly lead to more borderline pressure warnings showing up. I'd like a way to set my own center point of what the the RDC considers within tolerance.

[Lee]

if I liked to run my tires a pound or two more or less than BMW's recommended values,

You can do that without getting a warning on the dash.

[Pyrrho]

You can do that without getting a warning on the dash.

I've looked but couldn't find what the nominal range values are anywhere. How much high/low do your tires typically have to be to get a yellow triangle?

[Lee]

You can do that without getting a warning on the dash.

I've looked but couldn't find what the nominal range values are anywhere. How much high/low do your tires typically have to be to get a yellow triangle?

This question came up on the MOA forum and nobody could find that information.

We've had 6 BMWs with TPM and never had a tire leak so I don't know at what point the low pressure warning comes on.

Someone here can probably remember what the dash said for the PSI when they got a yellow triangle due to a puncture.

[Ray]

Someone here can probably remember what the dash said for the PSI when they got a yellow triangle due to a puncture.

Warnings for puncture can come while still within the programmed range:

"As soon as a relevant deviation from the specified values is detected, a yellow info light or a red warning light automatically indicates the loss in pressure. In addition, the warning is also issued when the pressure is still within the safe range but is falling quickly." - https://www.bmw-motorrad.ca/en/engineeri...y/rdc.html

[Pyrrho]

From pg 150 of the owners' manual:
Tire inflation pressure ranges
The RDC control unit distinguishes between three inflation pressure ranges matched to the motorcycle:
- Inflation pressure within the permissible tolerance
- Inflation pressure at the limits of the permissible tolerance
- Inflation pressure outside the permissible tolerance

and from pg 25:
Color of the icon
- Green: (OK) Current value is optimal.
- Blue: (Cold!) Current temperature is low.
- Yellow: (Low!/High!) Current value is too low or too high.
- Red: (Hot!/High!) Current temperature or value is too high.
- White: (---) There is no valid value. Instead of the value, dashes are displayed.

[Lee]

From pg 150 of the owners' manual:
Tire inflation pressure ranges
The RDC control unit distinguishes between three inflation pressure ranges matched to the motorcycle:
- Inflation pressure within the permissible tolerance
- Inflation pressure at the limits of the permissible tolerance
- Inflation pressure outside the permissible tolerance

and from pg 25:
Color of the icon
- Green: (OK) Current value is optimal.
- Blue: (Cold!) Current temperature is low.
- Yellow: (Low!/High!) Current value is too low or too high.
- Red: (Hot!/High!) Current temperature or value is too high.
- White: (---) There is no valid value. Instead of the value, dashes are displayed.[/b]

Thanks, I didn't realize those icons changed colors.
On our recent trip I didn't look at the My Vehicle screen much. I usually looked at the GPS for that stuff out of habit.
It would have been interesting if I would have seen a cold color when it was in the mid 30 and a hot color when in the upper 90s.

Here's a shot of my TFT. I usually run 38 in the front and 42 in the back.


   

[Duckbubbles]

A few years ago on my original RS I picked up a nail in the rear tire somewhere around Ozark, Arkansas. As far as i can remember the TPMS gave me a warning when the pressure dropped into the upper 20's. The warning light came on and the Nav 5 displayed the tire pressure in the rear in large numbers- enough to really grab my attention. Did a quick turn around and went back to a truck stop about 5 miles away, watching the pressure drop the whole time. It was in the mid teens when I got there. Plugged the tire and continued on my way.
TPMS is worth it in my opinion!

Frank

[Liteitup]

Similar experience, 27 or 29 seemed to be the trigger number. Pretty cool being able to monitor it when you know you have a leak.

[Grumpy Goat]

A few years ago on my original RS I picked up a nail in the rear tire somewhere around Ozark, Arkansas. As far as i can remember the TPMS gave me a warning when the pressure dropped into the upper 20's. The warning light came on and the Nav 5 displayed the tire pressure in the rear in large numbers- enough to really grab my attention. Did a quick turn around and went back to a truck stop about 5 miles away, watching the pressure drop the whole time. It was in the mid teens when I got there. Plugged the tire and continued on my way.
TPMS is worth it in my opinion!

Frank

I had a similar experience - high 20s was the warning. At the time I did not have a tire repair kit with me and got towed almost 100 miles using the MOA Roadside assistance - worked great. Tire was replaced under that same coverage as well. Both the TPMS and the MOA Platinum membership with roadside coverage were well worth it.

[Duccrazydave]

Same here. When the warning popped up, it was reading 27psi...just enough to make it that last mile to the house, lol.

[ESquared]

I'm trying to figure out if I have a TPMS issue or not, and my search turned up this thread, so here goes:

When I took delivery of my RS back in early April, I was surprised that the TPMS readings were down to 1/10th of a pound, and also surprised that the pressure stayed virtually constant for the first 500 miles or so. I've never had TPMS, so didn't know what to expect, but it started out great!

Over the past 200-300 miles, however, I've been fighting slightly low readings (35.2 front/41.3 rear, +/-, in that neighborhood), and no amount of topping off, bleeding and re-filling or anything seems to move the numbers in the TFT. I have 3 "stick" gauges, a digital version and the digital readings I get from my Ryobi battery-powered inflator, and they all confirm I'm now in the 38 front/44 rear range.

The TFT seems stuck where it was, and it won't give me a reading at all until I'm about 1/2 mile or so underway, which doesn't seem to be the state of things early on, when all I had to do was hit the button and toggle through the screens. Just double-checked it before writing this and no readings in any of the relevant screens. The "icon" with the exclamation mark shows "WHITE", which as far as I can tell doesn't mean anything.

I called Engle, couldn't get Ed in Service so I chatted with Peter (sales), who said they're just a general guideline, notoriously unreliable from an absolute accuracy standpoint and are best cross-checked with a good, old fashioned pencil-type gauge with a "square" (not flat) slider. I have two of those and they both say I'm above minimum.

So, my questions are: 1) Is it normal to NOT get a reading through the TFT at all while sitting still (engine off); and 2) Should I just not sweat it if I'm getting good cross-checks with other devices?

[Lee]

So, my questions are:  1)  Is it normal to NOT get a reading through the TFT at all while sitting still (engine off); and 2)  Should I just not sweat it if I'm getting good cross-checks with other devices?

To see the TPM reading you need to go faster than 20 mph. I don't remember the required distance but ours usually comes on in 200 feet or so.
It should not take 1/2 mile if you're going over 20.
As for accuracy it may be your gauges. On our R1200 and R1250 my gauge usually reads within 1 PSI of the dash reading when I first take off.
I use a chart to set the pressure. The TPM readout is compensated to 68F.
   
If it's 90F in your garage when you check with a gauge you need to read 38 and 44 on your gauge to get the recommended pressure.

[Lee]

The TFT seems stuck where it was, and it won't give me a reading at all until I'm about 1/2 mile or so underway,

When you talk to Ed don't get into the TPM display does not match your gauge.
Tell him the display seems to be stuck and it takes at least a 1/2 mile before it shows on the dash.

[Lee]

This is the gauge I use except mine has a rubber protective cover.
https://smile.amazon.com/Accu-Gage-RA60X...ljaz10cnVl

Noting fancy but it matches our cars TPM displays and is very close to our bikes TPM display when I compensate to 68F.
On trips I use the TPM display and for backup I use a Milton pencil gauge.

https://smile.amazon.com/Milton-S-921-Si...101&sr=1-5

[ESquared]

The TFT seems stuck where it was, and it won't give me a reading at all until I'm about 1/2 mile or so underway,

When you talk to Ed don't get into the TPM display does not match your gauge.
Tell him the display seems to be stuck and it takes at least a 1/2 mile before it shows on the dash.

So, it's true that the TPMS should read upon start-up, yes?

I went to the manual, and it talks about needing to exceed 19mph for it to activate, but my read of it was that it only meant the first time ever.  Here's the text:

Immediately after turning on the ignition, only dashes are displayed. The transfer of the tire pressure values does not begin until the following minimum speed is exceeded for the first time: RDC sensor is not active min 19 mph (min 30 km/h) (The RDC sensor does not transmit a signal to the motorcycle until this minimum speed has been exceeded.)

Yet, it seems that the picture in your post above (Lee) that you're getting a reading from a standstill?  Or was that enroute, after you'd exceeded 19mph on that trip?  Am I just being dense?

[Duckbubbles]

The TPMS will continue to display pressure for a short while after the bike has come to a standstill. I haven't timed it.
I wonder if, to save battery life, some sort of centrifugal motion is required to activate a switch internally in the sensor.

Frank