No sweat. Just don't run out of patients if it won't start right away. 50 degrees is not like 70 degrees. It wil take a few moments to warm up enough to start. Just use a good glow driver and turn it with an electric starter. As I said, it may take a few revolutions (maybe 20 or 30 seconds) of constant turning, but give it a go. Do it twice or three times till it starts. After it does start, it will be much easier to start once it runs out of fuel or you shut it down momentarily. Just make darned sure you run it very rich on the first couple of tank fulls no matter what the temperature is. Rich enough for the engine to pump out blue smoke and spit oil, and go from a smooth two stroke sound to a rough four cycle sound. Run it at a constant full throttle with a very rich mixture, for about 30 seconds, then back off for about 10 seconds, then back to full throttle. In the second tank, after about a half tank has burned away, lean out the mixture at full throttle till it stops four-stroke sound, run it for about 10 seconds, then back to rich for about 30 seconds, then repeat. This will give you the best results and will break it in.

You will get many different opinions on this. Even those that will tell you not to run it at full throttle at all.. but that's nonesense. I have 7 OS engines now and one Super Tigre 75, all broken in the same way, and they all run perfectly and have plenty of power.

DS.