@Calum yes I agree. That's good advice. Some parts it doesn't matter so much but there's certain things you just can't skimp on.

@NINJA thank you and yes I will as soon as I've worked out how to from Android phone. I have read callums post on embedding images so will have a go this evening when I get home from work. It is the blue one in my profile picture.

@Calum the beauty of 2 strokes is you can take the cylinder off really quickly. I'd definitely pop the exhaust off and look up the port. You can buy and endoscope for £5 that plugs into your phone

@scrimsmustang Would know...

Ensure the powervalve can spin freely inside the exhaust port. Dirty, gummed up valves will cause the powervalve to operate abnormally.