I just completed a valve check on my 2012 DL650 with 16,700 miles on the clock. I bought it 8 months ago at 13,800 and presume the valves have not been previously adjusted. Both exhaust valves on the rear head were at the tight end of spec. All other valves were well within spec. I did not adjust anything, just put it back together. When would you suggest I check again?