Couple details:
1: A #2 Robinson wood screw (square head) bent on a 90 makes a valve wrench.
2: You may need to disconnect the ignition wire leading to the coil in order for you static timing light to operate correctly, in other words you need to isolate the points "switch"
3: Get a JIS screwdriver instead of a Philips like I named in the video, JIS screwdrivers are like Philips in shape but they are designed to fit properly not "cam out" which is what Philips is designed to do. JIS screwdrivers and bits will fit the fasteners on these bikes properly.

Full service manuals HERE: http://ct90ct110.com/ShopManuals.html

Thank you for joining me for this short tutorial on how to set the timing and valve lash for many common Honda horizontal engines and four stroke Chinese clones. These engines were sold on pretty much any small bike you can imagine, Chinese kids quads, kids bikes, the fabled Honda passport and many many others. This specific tutorial is for a 1972 Honda CT90 but the principles in this video should apply to pretty much every one of these single cylinder horizontal engines with points.