Last night the check oil light came on for the first five minutes of a 30 minute ride. After work I'll check the oil level, but I don't know what weight of oil to buy if I need to add some. Any suggestions?
The oil light on those engines is an oil level light, where the oil light you might know from cars is an oil pressure light. The sensor for the light is just a float in a small tube bolted into the oil pan. If there is enough sludge in the pan, it can collect in the sender and make it stick after a bump. Or, you could just have low oil.
Checking oil means getting the bike up on the centerstand (checking on the kickstand will make you think you got no oil at all) and looking at the sight glass on the bottom right of the engine. There is no dipstick. There should be a mark, but the general rule is you should have a small bubble at the top of the glass.
Wal-mart: Shell Rotella T synthetic 5W-40 at $ 7 per quart. I have been using this consistently over the years in a variety of motorcycles and scooters.
5W seems a little thin to me. Yamaha says 10W-40 or 20W-50, depending on climate. I use 20W-50. Yamalube at the dealer can be surprisingly cheap - I've bought it for $12 a gallon on sale. At Walmart, I buy whatever they have for motorcycle oil. I think they have Castrol?
Second the oil change. Also, automotive oils may work well in some motorcycles. Others, not so much. The newer EPA regs have led to friction modifiers in some oils, which can cause slipping of motorcycle wet clutchs. Will it in yours? I don't have a clue- but it is not an imaginary concern.
People on Yamaha forums have reported that problem on the straight-4 engines. There isn't enough of a price difference between motorcycle and automotive oils for me to take that chance.