Recently I bought a working cylinder head off a well known auction site for £110, which, is amazingly cheap as it comes with everything I need to get the old thing going again (hopefully!)
I've removed the head and block and discovered the cam chain had pinched itself down by the main drive. This I rectified and now it's just(!) a case of cleaning, smoothing, polishing and then putting everything back!
Here's a photo of it in action...
...and here's a pic of it with seat, carbs most wiring and head off...
More pics and news on the revival of this old monster to come!