Looking at your channel there's a few simple things I can see that might help a little bit, or what seems to help me anyway.
- Upload regularly. Regular uploads help you keep subscribers when you get them. It's no use gaining a sub one week for another sub to leave because you're not uploading enough. Also the same for doing it to regularly, don't spam people.
- Thumbnails. Customs thumbnails are extremely important. There's a million motovloggers out there so you need to stand out. Personally, I try to keep a common theme in my thumbnails with text font and colour so people will recognise it's me. Give people a reason to click.
- Click bait. Click bait sucks but there is an in between area between click bait and a boring title. Be creative with titles so that you turn up in the search function more regularly. 'Ride from A to B' is a boring title but almost always there will be something that happened on that ride that you can market like 'almost dropped my bike' or 'pulled over by the police'. It's only clickbait if it's not true. It's not ideal but that's the YouTube game these days.
- Branding. Logo, banner, thumbnails etc. Make it all look good, fit a theme and be consistent. It's not just the videos that make people subscribe. Links to FB, instagram and twitter all help as well as subscribe cards in your videos. End cards are brilliant for pushing people who watched one video to your channel, social media or even your previous video.
Not sure if it helps but this is the stuff that I think helped me. Youtube is 90% shit and the rules for success were decided long ago so we kind of have to play to them