M5 x 0.9 threads
 

I dont know how you get round the problem but my petcock to tank screws, points cover, and points back plate screws are all made from unobtainium.

They all use 5 mm screws with 0.9 pitch rather than the now standard 0.8 pitch.

I got round the pet cock problem by tapping the tank to 1 BA which is very close and using Amal twist grip screws, common to most brit bike of the 60's.

I recently found these listed on the uk website of a chinese scooter supplier

M5x0.9 hex bolts in 12 mm 16 mm and 22mm thread length

and a 16mm long allen screw

Im going to check some local shops and see if these threads are common on chinese stuff.



http://www.chinesemotorcyclepartsonl...4ALLENM516.php