Just to add to this. My 2007 America had a service around four months ago and fork oil changed so not sure what original "Factory" level was. I decided to go to Progressive springs and I did the job myself.
I drained 530ml of oil and after letting the fork hang a few hours another 30ml of oil drained out so total quantity in the fork was 560ml. Given those numbers, I filled the fork with 600ml. Using a (Progressive Suspension) copy of the Triumph level adjustment tool I set it at 166mm and drained approx 40ml so that means I used 560ml which is exactly what I drained out.
Both forks were the same within 5ml.
It appears there is definitly a difference between the quantity and the height level spec in the Service Manual.
Not sure which one is correct but I will ask Triumph next week. The more accurate measurement is the height level as this takes into account any residual oil in the forks.
