When after going over a hump or hitting the bottom of a pot-hole, the front dips and it feels like the front shock bottoming out. If the hump or hole is big, / deep, then there may be an accompanying "slap", fueling the idea that the front shock is in need of servicing; having bottomed out.
The problem:
The rubber bushes (there's 2 of them) at the top of the shock have worn out; and are in need of replacement. They also appeared dry and cracked.


The fix:
BMW Part number: 31-42-2-311-994. Part no. 2 here:

It happened to mine, a 2001 model with about 58,000 km on it now. Looks like it had never been changed. Relatively simple change, need to pull back the fuel tank (I did not completely remove) and dismantled the front shock and swapped the bushes. Good opportunity to inspect the shock and clean up the area as well.


Cheers