Sorry, so should I bother checking them, or Not?
Whether you should check your valves at the recommended intervals, is really up to you. Some bikes will need valve adjustments and some won’t. Some bikes have hard use, and some have an easy life. Some bikes are run on good quality fuel, others are run on supermarket juice. Some bikes are well cared for and meticulously maintained, and others aren’t. I would say if your bike engine is working fine, you’re probably not in need of a check, but if your machine’s performance is a bit lacklustre, the first port of call should be to check that your engine is breathing properly; by checking the valves.We mustn’t forget, modern bikes have complex fuel injection and engine management systems, with significant numbers of sensors, feedback loops, and if one thing is out of alignment, it can be compounded by the other systems with which it is supposed to work.
The next time your bike is running a bit rough, don’t saw a hole in your airbox, buy a power commander, or snip any wires in your wiring loom. Tune up your engine the old fashioned way; check and adjust the valve clearances, and then take your bike for an Italian tune-up (good long run with blasts at high revs to burn the soot deposits off the valves)
Alternatively, buy yourself a Compression Tester like this one and check that your cylinder head is breathing properly. If your cylinders aren’t holding compression, then maybe it’s time to take the bike down the workshop and have the head checked, or have a go at doing it yourself.