Should i get my valves checked???

Ive had my machine 3yrs give er take but when i bought it the dealer said i should get my valves checked after 40hrs.. Ive got roughly over 100hrs of seat time.. Should i have gotten them checked or should i? I dont want to be causing any premature damage to the engine...



'07 TRX400ex

Maxxis Razr's 2 Rear
Tin Can Bumper
Stock Everything else..