Re: how do you adjust the valves on a vtwin Briggs and Stratton engine not a ohv
As far as I know Briggs never made L-head style v-twin. They however made an opposed twin. On them you first determine the valve clearances. If less than normal you remove the heads, remove the valves, and grind their stem tips squarely until you achieve the needed clearances. Don't over grind them or it new valve(s) time. While you got things apart you should go ahead and finish the job by doing a complete valve job. If the clearances are too much then someone has over grounded the valve stems or you have massive carbon buildup on the seat and the mating valve faces.
BTW L-head do tend close up the valve clearance due to wear of the valves and seats. OHV engine are right the opposite except it is actual valve or seat wear.