I have Porsche Cup Rims on my 928s4, sizing 235 front and 255 rear.
Now every few minutes the warning turns on for the RDK. It worked great before I changed the wheels. How should I proceed to tackle this?

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The original 17" CUP wheels with RDK-Sensors use a different mounting bracket for the sensor, so that the distance to the sensors is correct. Just swap those brackets too and you will be fine.


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Here are the part numbers you need for the 17"style brackets:

Front wheels: 928 341 087 01 13,73

Rear wheels: 928 331 083 02 16,04

It may become a problem when you swap wheels with a winter set since that would require the hassle to swap brackets too.

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So in 1997 I wanted to switch over to the 17" Cup wheels. But because of the work to change the sensor bracket and the issue not to be able to change back to 16", I decided for the 17" BBS with RDK sensors. These work with the old style brackets and thus I can still keep using my 16" winter tire set. They are front  2,5bar and rear 3,0bar as I swapped them from the 16"wheels. Normally you would get 2,5 bar sensors in the 17" inch wheels.