I knew this would happen, but I'm glad it did. I would go out and do all this jumping around to research oil, but end up with one false bit of info. That's where Wrightme43 came in. Good job!
0W= -35°C
5W= -30°C
10W= -25°C
When chemists test motor oils, they begin 0W at -35°C, 5W at -30°C and 10W at -25°C. The lower the WINTER rating, the thinner the oil. Thinner oils warmup faster. A 0W oil will start in the winter much more easily than a 10W. The problem with thinner oils is that they can't withstand as much heat.
Forget about the numerals. If you want an oil that STARTS easily in the cold, you want an oil with LOWER NUMBERS. If you want an oil that provides more HEAT PROTECTION, you want an oil with HIGHER NUMBERS.
One day I WILL go on a quest for the ultimate motor oil and chain lube. This cheap info will have to do.