Hi Steve

Sorry to hear your bike nipped up.

Yes, ideally the exhaust port bridge should be relieved after being replated and before use - to give the thin bridge room to expand. (As the bridge is thin it heats up faster than the rest of the cylinder and expands faster, & can sometimes rub the piston). I'd be surprised if the plater hadn't done this though, they usually know their stuff - it's their business to know. If the seizure is very light, you can often get away with super fine wet and dry if you are patient. If it has broken through the chrome, the best thing is to get them replated. On the piston, it's good practice (if you are racing) to relieve the piston ring groove at the point where it runs over the bridge. This you do with a small triangulated fine file, again this allows the ring to run freely in the groove should it get hot or the groove start to peen over.

Cheers

Dan
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