Just to clarify the tension. I was a bit vague in the video. When i say you should be able to move the belt a bit, but not a lot, I mean about 0.5 cm. My general rule is that if it makes a lot of sound, it's likely too tight. If you feel like you are scared it would jump teeth, it's too loose. That being said, tighter belts experience less sudden strong forces. This is a really short belt run, and the span of "acceptable" tension will be pretty large as it's not very prone to tearing unless you get foreign objects inside the belt/pulley teeth that wrecks it.

How to adjust belt tension on the SurRon Light bee X.