Royal Enfield says to set the valves with NO clearance. They say as long as the valve lifters turn (spin) without any up & down play, you're good to go. This goes against everything I know. It's a set-up not entiorely different from a BMW single. They say the valves loosen up as the engine gets hot. I'm really want to put a guage between the rocker end and the valve. I'm twitching. Am I nuts?