I also have a Cyclone and it didn't had a knocker, if it had one before, the parts manual would at least list it.

you may be mistaking the cyclone backbox layout for High speed since they are quite similar system.

Well, after looking it up again, it seems like I have been missing on that knocker the whole time without noticing it

So to make up for my stupidity since I should have done this first, here's a link for the cyclone parts manual: http://www.wwyss.ch/Arcades_Manuals/Manuals/Pinball/Cyclone_Parts_Manual.pdf
As a bonus, here's the service bulletin that is related to the cyclone, which I know would have helped me when I started working on my machine (it's not related to the knocker but it covers some missing info in the parts manual and a bit more): http://howtopinball.com/files/pinball/paperwork/williams/system_9-11/service-bulletins/Williams-Service-Bulletin-Book-1989.pdf

And finaly, the knocker assembly p/n is B-10686-2.

Now I have to order one for myself to get thwe full experience

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