I think you are correct Clive about 3/4 on the collet normal clamping range there is a slight taper then a ridge and a smaller diameter hole.
Good when members come up with solutions to questions thank you.
A bit of a change my friend has got the OK to attempt a steam water speed record at Coniston in a few weeks time.
Watching Guy Martins two wheel record attempt at Bonneville it shows you can never take anything for granted experienced record attempt breakers know the variables that can effect their attempts.
An acquaintance from my old days goes to Bonny regularly and was kept updated there were other class records broken at the Cooke Shootout. Guy was at.
Edited By Windy on 12/10/2016 00:56:03
Edited By Windy on 12/10/2016 01:01:52