what can be the implications of that?
dirty engine, nothing major, go for it
Along with rocks and other debris that the wheel picks up getting tossed at you.
Dunno about your part of the world but over here you need a front mudguard (fender) securely fitted to pass the MOT, so it follows that if you dont have one fitted your bike is not roadworthy, every traffic cop in the region would delight in jumping up and down on you.
Choppers do it all the time, but don't go through a puddle.
And, you never know where one of those puddles might show up.