why is it a waste of time? the shock still works well,no signs of leakage and the bike has low mileage the intention is to keep it as original as possible,early original naked K100s are much rarer than the RS or RT/LT and will have collector value in years to come.
how do you know it works well? have you had the damper on a dyno? low mileage or not, age dries out the seals. i have yet to see a damper more that 15-20 years old that is still effective. if someone is going to actually ride this thing, they will be much happier with a new damper that has a spring sized for their weight. not to mention new aftermarket dampers are better than the junk bmw put on these things when new.
LOL - i love K's, and love the optimism, but the concept of any early K bike, let alone a base model one, being worth money as a collector item in the future is really funny!