Hi but is ok to use10w 40?The only thing I can add here is to make sure the oil level is all the way to the full line. With only 1.6 qts. you don't have much of a safety margin. And Rebels are known to burn oil if run continuously at high speed. I also recommend an oil change every 1000 miles. It holds very little oil, is air cooled, and has no oil filter. Very hard on oil. Oh, and I would not use any oil thinner than 10w40, and make sure it is NOT energy conserving. You could wind up damaging your clutch. The Rebel uses an old school engine that is not designed for this new thinner oil.