Rayo: The Smartest Bicycle Tail-light

Rayo is a smart tail light for cyclists. This review will cover everything you need to know before spending money on it.

Why exactly do you need this?

When riding on the road, safety always comes first. Unlike motorbike or sports bikes, regular bike usually does not come with a front and tail light. Users will have to get their own tail lights. On one hand, most road accidents happened when drivers did not get to see a proper signaling from the cyclists. What’s worse, unexpected weather conditions can even further reduce the visibility. Therefore, cyclists are always advised to install a tail light at the very least.

However, most of the tail lights on the market are simply not good enough. Poorly made, low quality and usually does not last long. Well, you get what you pay for. The good side is, you guessed it, cheap at the price. You can always get them below $20 dollars. For example, this tail light that I found on Amazon is so far the best in class. It has tons of customer reviews and an “Amazon’s Choice” on it.

If you are someone who’d rather go for a little bit higher price with good quality, Rayo is certainly worth the price.


Rayo features a 90 lumens ultra-bright LEDs and it’s customizable to the flashing patterns of your choice. To compensate blind spots and for better visibility, every single Rayo tail-light equipped with 3 LEDs where each shooting at different angles to cover larger distances and areas.

Specifically, it uses Total Internal Reflection (TIR) optic lenses to focus and directs lights to the rear and both the sides.

Rayo is so bright that it can even be seen on daytime.

Another cool and useful feature is the smart brake system. Rayo comes with a built-in 3-axis accelerometer and a 3-axis gyroscope sensor to detect when you are slowing your bike down. It gives off brighter signaling patterns to warn the vehicles behind you instantly.

This automatic brake system is certainly helpful as it could be life-saving especially in the nighttime.

But, what’s that for?

Instead of flashing randomly, Rayo allows riders to synchronize the lights as a group. By displaying the tail light simultaneously, it alerts nearby drivers, pedestrians as well as other bikers that they are coming in a group from afar. Rayo also features a mobile app connectivity to the smartphone via Bluetooth. I certainly love what it brings to the table as you can see the remaining battery, configure the light patterns, and lastly, a theft alert where notified you someone tampered your bike. One drawback is that you will have to connect to your Bluetooth all these while. In other words, it will be disconnected if your phone is out of the Bluetooth range (typically less than 10m /33 ft).

Rayo is IP67 water resistant. IP67 means it’s protected from dust and capable of immersing in water depth between 15 cm to 1 meter.

The installation is fairly easy. Rayo uses a flexible strap to lock on the seat post without any tools needed. Next, tap (touch control) to turn on the lights and you are all set.


For the battery, Rayo is using a 1200 mAh lithium-polymer rechargeable battery. It provides up to 20 hours of run time in low power mode. However, it takes roughly 3 to 4 hours to fully recharge which is slightly longer than expected. That would be good if the creator can improve on the USB cable so that to make charging faster possible.

Price and Discount

Rayo is available in multiple colors including pink, blue, white, black and yellow. The price starts at only $35 (now $49 on Indiegogo) for a limited time on Kickstarter, grab one fast if you can and enjoy up to 53% off retail price.