Dealer just installed my new Hot Cams in my 07 WR450F. 4 out of 5 valves where on the tight side so they had to re-shim. The correct shims where not in stock so by the time the order came in there was snow on the ground. Cams are installed and in spec now but Hot Cams recommends a 30 minute break in under light load but over 3000rpm and then clearances checked again. This will not be possible to do now due to the snow, is it critical to be done?