It's always a good idea with any bike to replace all the fluids etc so that you know it's all good. And since the coolant has been drained you may as well whip the barrels off. I could show you a pic of the head that came on one of my bikes....... luckily I was changing something at the time and checking things. It was nasty, like some metal had been in the chamber, and the "bike shop" had just ground down any impact marks with a small stone!