I just bought a 1964 YG1-K and i'm having trouble finding information about it. Dose anyone know how much gear oil the bike takes and what kind? The bike dose not have a dip stick or a sight glass so i don't know if the gear oil is ok.

In the UK the amount of 10w40 motor oil to be added to the gearbox was stamped into the casing just by the filler hole to check the level see this from memory there was 600 cc of oil in the gearbox but don't quote me  

couldn't find the stamping. thanks for the information though, i didn't even notice there was a little filter there until now. 

lts 400 to 450cc, i brought the manual. lf you need any details from the manual let me know and i will scan it for you