OK then, the good news first: We can rule out the gearbox being at fault as it does it clutch in or out. Yours would appear to be a 2009 model and we have historically had a few gearbox problems with these which is why I asked about it's age.

Next port of call is probably to (as Pepsi intimated) examine the primary drive gear and in particular check that the the crank nut is still tight. You may want to read this thread, rather than me explain it all again!

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