My mot man had had a spot check at his shop and had not challenged the off road exhaust so he has become more on the ball for a while. He tells me that the loadness is down to the tester so long as it is not excessive but info on pipes is still checkable. I have heard of other garages turning away bikes because of this rule. Fortunately just got a smack bottom. Managed to remove the print with scotch bright. Just need to gloss up the chrome as it has flattened the shine. Can take to him now. Happy days, if ever the weather stays nice long enough to enjoy it.