What type of synthetic oil should be used for a Coleman Generator with 11HP Tecumseh Formula Motor below 0?

I have a Coleman generator. In the summer I run 30 oil. In the winter I have been running 10w30 but I still find it hard to start on cold Canadian winter night. I would like to use synthetic oil to help with the starting. (recoil start) Is there any reason not to? What type of synthetic should I by?What type of synthetic oil should be used for a Coleman Generator with 11HP Tecumseh Formula Motor below 0?
i wouldn't use synthetic, it will be more ';gummy'; when cold than regular oil. try 5w30What type of synthetic oil should be used for a Coleman Generator with 11HP Tecumseh Formula Motor below 0?
I only use Mobil One and Klotz, Check into Klotz, low viscosity Synthetic. It is usually used in Motorcycles and Quads, among alot of other air cooled engines.