Hi Phil,
Richard Slater had no axe to grind when I asked him "fairly recently " (having read John Nuttings article in Classic Motorcycle Mechanics July 2015) in order to clarify the 3CE spec which this & other period tests had indicated focused on the free flow exhaust system for the 3CE model & I can see the exhaust mods being implemented first as its a relatively easy mod, also probably giving the biggest single gain in power. HC pistons & wilder cams would be a waste of time unless the engine could breath properly first. Perhaps on going development & racing gave Roger the idea to sell more hot up parts to more well healed clients in order to increase profit margin on the machines which then lead to developing the Jota with the factory as a production model.
Your observations on cam timing is interesting & maybe I was lucky with mine. I remember Steve Winterton meticulously checking & setting up the Bosch CDI ignition triggers properly when the exhaust & carb mods were done by Slaters back then. Two guys I knew at the time had Jotas & I never felt at any disadvantage on the road on my modified 3C, I guess what i occassionaly might have lost at the top end i gained at the bottom pulling out of corners. It was a lot sharper though than a friends standard Jarama.
Give & take it was on a parr with my brothers Kwak 1000J & Eddy Lawson replica but i could leave them at 120 plus with my drop bars. We had a great trip together from Hereford to northern Germany then down to Narbone south of France & back. I recal a well ridden GS 1000 & Katana were a close contest. A Honda CBX could out drag it in a straight line but i could out corner it easily & leave it at 120.
Those were the days...
I drilled and tapped at the red arrow ..... iPad now fucked 
thanks for the advise.
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