Don Ashton's design suggestions for 'Speedy' valve gear were published in Engineering in Miniature, Volume 30, Nunber 7, January 2009, pages 234 -236 inc., under the title 'Speedy Revisited'.
There were also a couple of follow-up letters, but they do not seem to have contributed anything directly to the technical design.
As you probably know, Mr Ashton is an active participant in the other forum where you have posted your query, so if you have any technical difficulties on that front he wil be able to assist you directly.
I'm sure a 'Speedy' builder wil be along shortly to assist with your design conflicts.
Regards,
Phil
Edited By Weary on 31/10/2013 16:02:59