I finally got to take the K100RS for a longish run on the weekend; about 500Ks in total.  She purred along beautifully, well at least until I discovered that the fuel warning light on a K100 is nothing like a Ducati's... when a BMW indicates it is time to fuel, it is !   The look on OZMaz's face when she came back to find me was priceless.

Anywho - on some of the roads the front end made a kinda clunking noise on rebound - almost like the springs were topping out and the forks were slapping back down onto them.  I have Ikon progressive springs in the front with NO spacer, as recommended by the supplier.   The forks appeared to be in good condition with no undue wear when I inspected them and changed the oil; the bearings are good and torqued down correctly.

Does the K100 normally have a noisy fork action ?

Hoppo

Hi Hoppo.My 4valve rs does'nt have a noisey fork action and i had to use serious force on them  when i first got the bike as the stanchions were jammed in the sliders by a bush .

I have never noticed any clunk except for loose head bearings once

Hi Ozhoppo!
 Sometimes Big Reds fairing rattles/clunks over really rough roads.
A fix is in order when I paint her this winter.
have you checked yours? It could sound like it comes from the forks. 

there is another source of noise as well
associated with the  through tripple tree brake line (y adaptor under the forks lower bridge )...
they often rattle inside the verticle tube of the fork pivot

there is a fix

I had clunking noises from the forks. Ended up being a broken spring and a hand full of these stuffed in the top.

hmmm, maybe these broke the spring   

Found something similar in my forks.After fitting new bushes and seals i put them back in.Figured some one must have put them in for a reason.The spacer may have been trimmed,don't know as it was the first time i have dismantled a set of forks.They perform fine and if i ever get broke i can always pull the forks apart and get the 20 cents back.