Don't see the valve adjustment issue very much on the v-twins, it is mostly the single cylinder 14.5-18.5 hp engines. What I do see more on the twins is either the compression release spring breaks, or the flyweight sticks, or the lobes on the camshaft wear down and don't open the valves. All three of these conditions require camshaft replacement.
All three conditions will act like the compression release isn't working because it's not.
To check it remove the valve covers and turn the engine over by hand watching the valves to make sure the fully open and close. If the compression release is working you will see it bump either the intake or exhaust valve open just before top dead center compression stroke. If the valves don't fully open replace the camshaft. If the valve doesn't bump open as described replace the camshaft.
Also check the valve clearances to be sure. The clearances are .004-.006 inch. Roll engine over to just past top dead center compression stroke on one cylinder and insert a feeler gauge to check clearance. do same to other cylinder. The adjusters may either be a lock nut that you loosen then adjust clearance with inner nut, then retighten lock nut. or will have a single nut with a torx head screw in the center. Loosen nut, back torx screw out insert feeler gauge turn nut to proper clearance and then retighten torx screw to snug. Do not overtighten because can crack main nut.