[CSR_Sprocket]

Page 29 of the online owners manual does state 1.6 quarts. My local car parts store only sells oil in liter bottles so that's my reference point. When I put 1.5 liters of oil in the crankcase the sight glass was completely covered and the oil registered about an inch too high on the dipstick. I used a catch pan and quick fingers to drain the excess. A glass pyrex measuring cup showed that there was about 500ml too much oil in the case. So with my Hawk one liter fills the crankcase 1/2 way up the sight glass and registers at the top of the crosshatch section on the dipstick. Which should be the right amount as far as I know.

Echoing motopat's above post, both the sight glass and dip stick shoukd give you the proper reading. I rest my kickstand on two pieces of 2x8 plus a 1x1 to get the bike to sit just left of level. I then tug the handlebar gently until I feel the balance point. That's when I check the oil level.

Add too much oil and it'll be blown out the crankcase vent tube and into the air filter box. The oil spray might saturate your air filter. The stock filter is designed to run dry. In another thread someone mentioned that a particular lawn mower air filter is an exact fit...