The ball joint should be replaced if the boot gets torn or any high mileage bike. If you are installing the Wunderlich WRA Lower clamp on your R1200 GS or Adventure, then we also suggest that you install a new ball joint if your bike has more than 30,000 miles.
Original BMW part number: 31 42 7 652 644 ( 31427652644 )
Please Note Model Fitment:
Fits both top and bottom fork clamps on the following models: