Hows your clutch adjustment? if its not disengageing the gears properly it will certainly hang on to the fingers on the selector drum and then jump from one gear to the next making it difficult to get neutral. try going for a lighter viscosity gear oil......
nupp go silkolene 10w 40 semi synthetic and you should only need around 1 litre.
use the dipstick to check the level when its screwed all the way down and make sure the bike is on a flat level ground and level sideways as well.
Newb here sorry, i though it would need to be filled to the brim. When i started it after the new oil is was making a funny sound like it was grasping for air.
yea that jumping gears problem happens to me too, when you roll it it feels fine but then when you kick it it jumps forward?? my friends did it too once, and he was facing downhill. it was so funny. lol.
I know of a first year Mechanic who did this to a customers car! For a punter to do it is silly but for a apprentice who you would think should have some idea that is dumb.