16K km is ok for valves, no specific need to check.

As petenz mentionned, glowing pipes are normal is you stay idle a looong time (specialy after use...).

hard fan use? thats normal, i find mine working hard too if necessary, you can "Stop" the bike juste after fan stopped and chec in diag mode what temperature is the engine.

tenere are a bit different for the airflow (cooling) so the temperature can be diff�rent.

every bike is diff�rent

good idea to check Air filter and clean it...

my experience : mine is stock, i got since April - 4K km done (+service at yamaha at 44500Km, and now is 47K ). i decided to put money in just for one Modification : Air filter ! i bought a KN, and i feed the bike better, like it breathe better. this is my advice, buy a filter (KN, DNA....) best investment ever !!! it was like 70€, but clearly worth it (durability, and for the bike)