The original comment about the oil referred to the excess fuel injected while the engine started and warmed up. That can definitely get into the gas, and as short as the run was before it was drained could definitely contain some gas that went by the rings into the oil. Heating the engine up properly will evaporate the gas. If you read the instructions from the oil sampling kit, it tells you to get the engine and oil HOT. Now, given the cold natured state of the enfield engines, you probably need to run a few miles on a freeway to get them anywhere near where they should be for sampling.
As far the temps these engines get to, I checked mine after a 35 mile ride with the last ten miles going up a mountain on a freeway and checked the temp while it was still running as I stopped at a gas station right off the freeway. It was in the low 60s air temp. The oil temp was about 182 degrees. That's really about the minimum you should have it for oil sampling.
There was a thread about this subject last year when one of our Alaskan members was noting that his oil temp would only get up to about 130, (that was about the temp he said +- 10 degrees) in 40 degree weather. Prompted me to check mine. These things do tend to run cold!
Bare