Engine oil weight, etc????
 

Newbie here again,
Got the 110cc quad the other day, Eagle brand, aka Zhejiang Peace Trade Group,lol. After setting it up, took it for a spin and this little things purrs like a kitten, more than the 7 yr old will need, had to turn the screw for the throttle in almost all the way.Was reading the owners manual and it calls for 10W40 oil, this seems a little heavy to me. Anyone else have any ideas what I should use? I would like to get the factory fill oil out after a few hours and use a quality brand name. I also am wondering what screws do what on the carb if I need to fine tune it. I know which one empties the bowl for the gas, but there are a couple of other screws that I am not sure of the function. Thanks for any help. The owners manual appears to be a generic "cover most" models type manual, but the parts book is quite specific to this model.

There's only 2 screws other than the drain. The larger screw with the spring is the idle adjustment and the smaller inset screw is the mixture adjustment.

Is there a way to determine what the proper mixture setting is?
It seems to run fine, but I am just curious.
Thanks