bad shifting?

only use proper motorcycle 4 stroke oil from a bike shop.

anything in this range depending on the normal air temperatures -


Dave

 

I now religiously use 10w50 in my 3LN.
20w40 just didn't agree with the bike, made it hard to start on cold mornings and also felt like it was robbing a little bit of the top-end.
15w50 was better, but still occasionally difficult to start on very cold mornings.
10w50 is where it's at for my bike. Runs smoothly, starts instantly, and powers right through to redline.

If your getting a little smokey using a thinner oil like a 10w50 then it's probably a good idea to use something like the 20w40, but otherwise... any or all of the above will be fine.

 

Depend on what the manual states for the position of the bike. Some bikes are checked on their sidestand.