It depends. But my overall interest is someone's passion for two wheels. They can be talking about anything as long as I know they are loving the ride.
Now if you are referring to stuff where someone throws in a video that has nothing to do with motorcycles, and isn't on a motorcycle, I might not watch the whole thing. Say a motovlogger goes fishing but gets there by cage and then goes out on the boat and never mentions bikes, I may not enjoy that video. Or I might, but if that became the norm then I might not watch as many of that vloggers videos as I do not enjoy fishing. But if they ride their bike out to their favorite watering hole and pull out two or three trout and bring me along for that two wheeled adventure, never talking about bikes, I would be in for the ride and the hunt.
I like to watch videos where a person's personality and joy of whatever they are talking about is strong, I prefer on bike. I tend to only watch bike reviews or how to videos from channels I currently sub to and know the format they will go with.
Now I will search YouTube for how to vids if there is something I need to learn, but I am not watching those videos for enjoyment or entertainment.
When I bought my new bike I was researching travel on a motorcycle and found 2 channels that got me ready for my travel. 40 Times Around and he led me to As The Magpie Flies @themagpie . I still watch these channels because I enjoy the content even though my trip is done and gone. Both of these channels also do more stuff off the bike but it is bike and travel based, I find I enjoy what they are saying or teaching bike or no bike.
I research anything I am thinking of purchasing through YouTube as well as regular web search.
I have found that if someone has something that is a compelling topic I don't care if they are on the bike riding or standing next to it. RocketRyder510 doesn't do much on the bike at the moment but I find his camera work stunning.
Reviews and guides get searched for, vlogs don't... so to grow an audience you need to make content people will search for, but to keep an audience you need to make content people can relate to, so IMO, you need a mix of both!
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