Videos
Here are some video links on various subjects, the sources should be apparent on the video, our thanks to them all.
Variator Removal and Weight Change
Valve adjustment; this guys procedure is good but most would disagree with his settings. About .004" intake and .006" exhaust on 150cc is common, although there is lots of discussion on this; and about .002" on 50cc, again, much discussion. View Valve Adjustment Video
Here's a bloke who likes his caffeine explaining rectifiers/regulators, just take some dramamine and enjoy, there's some good info here: Part I Part II Part III