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Rotary valve Manx Norton engine
A whole coachload and more have contacted me via varying routes regarding the drawing of a Manx Norton engine fitted with an experimental rotary valve used in the TCM technical feature (‘Engine tuning, pistons,’ October 2018, page 96). In fact, the in tray bulged so much I simply can’t reply to everyone individually, so please accept this as my personal reply to you all.
In every feature I endeavour to give as much value as possible. In this instance, rather than include a few random pictures of slipper pistons, I plumped for the rotary valve Manx Norton engine drawing on two counts. Artistically, it’s a super drawing which could grace the wall of many a workshop, plus it has the added interest of the rotary valve concept developed by Norton 1952-54.
A number question if any engines were ever built and why did Norton opt to use a slipper piston with valve cutaways when they weren’t needed in this case. The quick answer is yes, and because they used stock Manx Norton pistons off the shelf intended for their familiar large poppet valves. But from your correspondence I know you want more.
Research suggests the first rotary valve fitted to an internal combustion engine was to the Crossley low speed industrial/ stationary engine built 1886-1902 by Crossley Brothers Ltd of Openshaw, Manchester. Many others developed designs which some
