Jamie, Here are the PDF copies of the pages from the G!MRA Newsletter in 1982. I think they will appear at attachments which you can download. Haven't done this before so we'll see what happens. The first two files - JG-Gear-01/02 - are the excerpts from my letter to the newsletter describing the differential driven valve gear idea. The next five files - JvRPage01 - 05 - are John van Riemsdijk's response in the following Newsletter with a full description of his gear driven valve gear. The last two files - HinesDrainCocks01/02 - I just happened to come across and remembered your recent discussion about working drain cocks. This is a simple idea which you might be able to hide successfully on your cylinders, especially if the "drain cocks" can be fitted almost under your valve faces. Jim.