In a Tao Tao CY50 A, I've read to use 5W30 and 10W40 and even 15W50 ... so I'm a little confused. I live in Las Vegas and temps can reach 115 degrees in the summer and around 50's in the winter months. So, what's the best motor oil to use. Couldn't find any Tao Tao recommendations. I currently have 5W30, but some say it's too thin. The consensus seems to be 10W40, but I ask here because at the same price, I, naturally want the best for my scooter's engine. What say you?
I keep hearing in the Winter months, its best to use thinner oil. My manual (for my scoot) recommends 15W-40 (and I know we basically have the same scooter.) Since that is hard to find, I use 10W-40 Motorcycle Oil (from Pep Boys, it's on sale right now, too.) Make sure u get the motorcycle oil, tho. Better for our hard working engines.
15W40 is the best for summer. 10W40 for the winter (if you're living in S-Florida; If you're living in Alaska or other super cold areas, 10W30 might be better for you). You can notice, when the engine vibrates more, you'll have to get thicker oil.
Thicker oil (like 15W40) will make your engine run smoother, and will make the engine last longer. You'll notice less engine vibrations in the frame, which leads to longer frame life (as strange as it may sound; meaning less chance of bolts vibrating out of their places, less chance on electrical cables to wear or tear or rub against other vibrating plates, etc). Thinner oil (like 10W30) in some cases will improve performance like acceleration and top speed. It also allows for better idling in winter months. Generally thin oil is used to temporarily improve performance of bikes, like when you want to show off a bike, you'll fill her up with thin oil, to make her go faster. However thinner oil always leads to the engine to wear sooner, as well as the bike's wear is increased.
If I where you, I'd do an oilchange in the spring time, and in autumn. 15W40 in spring, 10W40 in autumn. If you're not driving a lot, and don't want to waste oil, you can always gather the oil in an oilpan, seal it, and fill up the bike with the that oil again in 6 months, when it still looks like it's good oil (not dirty, very few metal flakes in it, clear and transparent yellow, not black).
I'm a newbie as well. I just got lucky enough to experiment with different oils, and figure out what fits best to me. I neglected to say, that the oil type depends on where you live, and the outside temperature (as well as on the bike). Most bikes have the same internal temps, but if you're living in cold or hot temperatures, engine oil type could change as much as 5 to 10 numbers higher or lower.
If I where you, I'd not completely drain the engine, but just add some oil thickener in it, like motor honey, and do an oil change later (that is, if you're living in a hot area). If you haven't completely filled her up with 10W30, you could add some more of 15W40 in it. Both oils will mix and change the overall viscosity of the oil just fine (some people are against it, but when an engine is running,it mixes the oils quite fine).