Yeah the CR piston is pretty obvious, thats what happens when she's pinging her head off and you ignore it. Combination of lean jetting and old fuel, oops. Had the jets on order too, thought i'd get one more ride in.
The TM's a different story, Was starting to feel a bit soft so i pulled the barrel to find the piston looking like that. What a mess, Pretty disappointed actually this has been the first real problem with the TM. To be honest i'd noticed some porosity in the casting previously and was never happy with the quality of the nickel plating in the barrel but didn't think this would happen.
Oh well off to the platers. This still doesn't change my opinion of the brand though, The majority of the other components are of a very high quality and beautifully made. Wish they'd payed bit more attention to the plating though.