I realised as this was unlisted, I'll not be able to watch this at work.
Great first attempt buddy, it is tough figuring out the gremlins etc, am sure you will sort them.
Feedback offered, but please don't take it as gospel or criticism...
Would have been good to showcase the bike better as it is you introducing it to the channel, and also is the topic of the video, maybe a walk around and point out highlights and features as well as just showing us the bike a bit more.
I'd also suggest making the topic/title a bit more related to the content... this video seemed more about a ride around your local area, which is fine, but not really on topic for the title.
Your audio is fine, but like you say, picks up breathing and wind... You mentioned moving the mic, I think that will help a lot, but wasn't an issue in this video with the mix of on bike, and voice over... but be mindful once you start going a bit faster. I loved your observations while riding, it showed that you were very much paying attention to the surroundings, and had an eye on potential hazards etc, well done!