
I built this with the concept of keeping costs down, making it compact, and easy to attach and detach (‘ω’)ノ
World’s smallest (allegedly)
motorcycle helmet dashcam with front and rear 2K recording SJCAM C100+
This is already version 2, and it’s nearly complete.
The primary role is that of a dashcam.
I’m not going for the typical YouTube approach with gimbals for smooth footage.
• Keep it as compact as possible
I learned from mounting a GoPro on a helmet before that weight balance is extremely important. Even a little extra weight will tilt the helmet. It’s crucial to keep it small, lightweight, and positioned close to the helmet itself.
• Keep costs down
I might drop it, I might hit it and break it, or it might fly off in an accident.
Thinking about that, I don’t want to spend too much. If I really wanted the absolute smallest, INSTA360 GO 2 would be the way to go, but ¥32,670 × 2 on Amazon is tough to swallow.
That’s when I landed on SJCAM C100+—just ¥9,800 per unit.
The INSTA weighs 27g while the C100+ weighs 33g, so the difference is negligible.
• Loop recording is essential
Unlike GoPro, this supports loop recording mode where old footage gets overwritten.
You can also set recording duration to 1, 3, 5, 10, or 15 minutes, which makes reviewing footage incredibly convenient.
• Long recording time
2K 30fps gives 2.5 hours of continuous recording; 1080p 30fps with WiFi off allows 3 hours of continuous recording.
GoPro definitely can’t do that. With this battery life, I can handle a one-way trip, so light touring and commuting should be no problem.
• Quick-release with Quad Lock
One-touch removal makes charging and file transfer a breeze.
Angle adjustment is done by loosening bolts and shifting the bite position, so once set, it won’t move.
It’s also convenient when I need to charge or transfer video files.
• Date and time stamp available
It records exactly what time something happened. You might even become a witness to history!

The camera is angled quite upward, but that’s to match my helmet angle when riding.
I tend to tuck my chin when riding, so this is the position I ended up with.

This is how the rear looks. Once the front is set, the rear automatically aligns.

This black bracket is made by fixing two included back clips with two-part polyurethane adhesive.
These back clips are excellent—they have sturdy claws that lift up for one-touch camera removal (*’ω’*)
The downside is there’s no image stabilization at all (though it’s manageable while riding a bike).
The unit is only splash-resistant (I’ll verify this), so heavy rain might be tough.
Still, I managed to build a front and rear helmet dashcam for about ¥25,000 that I can use all the time, and I’m really happy about that.
If I capture something interesting, that’s a bonus.
I’ll upload it to YouTube when I get a chance (I’ve been slacking a bit).
