I just finished doing this to my bike.
18 s1000r with 8837 miles.
I had been noticing a cold start rattle since around 6000 miles and found out about the replacement silver plug but was told to wait until at least 8000 miles.
That plug was a bear to thread back in with the tensioner pushing out on it. I'm not sure if there was an easier way but I managed to get it in.
Cranked the bike after the install and got the same one to two second rattle then quiet on the next couple of starts but that's pretty much the way it was before.
Now I'm kinda worried that I did this for nothing and wasted almost $50 lol.
Might be too soon to tell. I'm planning on a ride tomorrow.
If the cold start rattle continues should I put the original black plug back in?