Cameras are like motorcycles. There is always some more bling and some more niceties to add to make them work better. I have been culling some of these down, and thrown away some of the rarely used stuff that I have. This the final list of all the glorious stuff that made the cut. As a bonus, here is a shot of all them in my tankbag. 

• AmazonBasics Travel Tripod: A good tripod is essential for night shots, and for good panorama photos. It's light weight, fits into the panniers, is tall enough, and the whole rig looks sturdy enough to me. What more can I say?
• Neewer Intervalometer: An Intervalometer is a must for taking timelapses. One of the ways that Sony did cost cutting on the A6000 is to charge extra for software that in my opinion should have been standard on the camera. Sony has a timelapse app for $10 in the camera's app store. The problem with the app is that it is restrictive in it's shooting options, and some users claim it's buggy. I decided to go with a hardware intervalometer. They are cheap enough on amazon, have the full gamut of options to choose from, and allow me to set any shooting mode I prefer and it is satisfying to click on a few buttons before starting the shoot. This also fits nicely into my tripod bag.
• Fotga Variable ND filters: Works as a lens protector, works as a decent ND filter, and since it's a polarizer, it can be made to work in that application. Not the best optically, but I can't complain for 15 bucks.
• JJC IR Remote: This one has a lot of bells and whistles that I don't really need. But, it allows for a remote shutter, and timed shutters as well. It's also simple to use, and IR on the camera doesn't drain the battery as much as the wifi.
• Lens pouches: Lens pouches are just lens pouches. I go with the cheapest I can find. That said, I am also experimenting with these right now, and they seem much better for a little extra space. The Sony adapters came with hamburger bun pouches, which I really like. I don't use a dedicated camera bag, so I would rather not skimp on this part.
• DSLR Sleeve for padding: I keep the a6k with the 18-105 in one of these. Not sure if it adds any significant protection, but it doesn't take much extra room and gives me a piece of mind.
• Extra Batteries: The a6000 eats batteries like crazy. Always good to have a backup. Or two, in my case.
• Dual Charger: Do yourself a favor and get one of these instead of the wasabi charger. This charges two batteries at a time, and needs only microusb. You already have several microusb cables at this point, so this blends in very well. I have found that this can charge the batteries in around 3 hours from fully empty. It can also do solo battery charging.
• JJC Wrist strap: More compact in the tankbag than with the shoulder straps, and still really comfortable to hike with, even with a big lens. Added bonus - doesn't interfere with the tripod setup, and is quick detach, even though I don't know why.
• Nissin i40 Flash: I haven't made up my mind yet, but I might probably pick up one of these before I start. The problem is that I am already running out of space, and I think I can get by with the amount of gear I have.
• Aftermarket DC coupler: This is for when I want to take extended timelapses. I have a 12V->9V DC converter as well, which plugs into my jumpstart battery and gives 4x the number of shots from the camera. This setup is nothing fancy, I have a DC step down transformer that converts 12V into 7.5V, with DC 5.5mm pins to connect to the jumpstart battery.

POV Camera

It isn't a riding video if there are not videos of the riding. Go Pro is the king of this market and for good reason. I don't have anything against Go Pro, but I went for the Sony AS100V Action Cam. Similar feature set, usually more cheaper. When compared to the Go Pros, these are the pros (ha!) and cons:

Action Cam Advantages:

• Built-in stabilization. It is electronic, but it can at times go a decent job.
• The form factor is more aerodynamic than the Gopro
• The microphones on the action cam are far better. They are better than even most DSLR mics.
• Uses standard camera 1/4 inch screw mount, makes it easier to reuse my tripod
• Has the slight edge in image quality
• The battery lasts slightly longer ( 2 hrs vs 1.5 hrs)

Action Cam Disadvantages:

• Gopro has accessories like no other. The action cam is a distant second here.
• Gopro can connect to a Sena headset for audio. This is a huge feature missing on the Sony
• You can go to any corner of the world and get parts and extra batteries for the Gopro. Good luck doing that with the Sony system

Overall, I think the Go pro might be better buy here, mostly for the ecosystem. I have the Sony so that is what I will be using. I also have the following accessories from the Sony ecosystem, for helmet and bike mounting:

• Tilt mount
• Helmet side mount adapter
• Handlebar/crashbar mount 
• Dual charger that takes in a microusb cable
• Two Spare batteries

Sound

• Tascam DR-22WL sound recorder: A video is as good as the sound it has. I guess since the dawn of time, cameras have sucked for recording good sound. An external sound recorder works wonders. The Tascam DR-22WL is the new best cheap/entry level sound recorder, in 2015. It is regularly part of bundles with other pro gear, so if you check ebay or your local craigslist, you can see that it can be had for much less. The sound is really good, both with it's built in mics and using an external mic, it supports wifi, with remote recording controls, and can be powered by usb as well.
• Cheap Lapel mics (One is taped permanently to near the exhaust). I carry three or four of them, to use with the Tascam. They are good enough for the price. I won't record concerts with them, but for interviews and general microphone use, they can't be beat.