Monkey Light M232 review

While browsing Amazon for something cool, I happened to notice an item for sale called "Monkey Light". It's a circuit board with some LEDs in a row on it, which you attach to the spokes of your bicycle. When the wheel turns it sweeps out an image in the air.

I bought the light and decided to write this review of it as a justification for the fun purchase. I also bought some similar competing products so that I can see if it's better to spend quite a bit more on this US-made product or if one of the sub-$20 Chinese ones will do.


Maybe my desire for neon lights started after seeing bikes zooming around neo-Tokyo in the classic 80s anime Akira. Now years later I am actually living in Japan, but where's my neon-lit bike? 

As an adult I thought that it might be a bit childish to light up my bicycle like this, so I decided to... just go for it anyway. I couldn't decide which lights to get, so I bought various kinds. To justify the purchase, I intend to try out a few of them and write a short post about each, finishing off with the grand finale post which compares them all.

Wheel light skepticism

This M232 version of the Monkey Light only has a single LED strip with a total 32 full-color lights. There is a more fancy pro version that has multiple LED strips for a total 256 LEDs, but that one costs almost $1000. To me that's a pretty ridiculous amount to spend to just light up your bike, so I'll be sticking with the $50 version.

To get a full image that covers the whole wheel area, the strip would need to rotate fast enough to sweep 360 degrees before the "after-image" in your eyes starts to fade. A bicycle wheel only turns about 3 times a second, which seemed like it wouldn't be fast enough. 

I must admit I was quite doubtful of how striking the effect could be. I had never seen one of these in real life and was only relying on pictures, which can lie because of unnaturally long exposure times. After getting the light, I must say I am pleasantly surprised how strong the after-image actually is. It seems to last for about a third of the second, which is almost perfect to get a full circle if you are riding fast enough. 

Initial impressions of the package

The company that makes this is in California and called Monkeylectric.

Looking at the instructions online and upon the package arriving, I was feeling a bit overwhelmed by all the stuff in it. I can't even change a bicycle tire. Will I be able to install this? So many little parts! And the device itself just looks like an exposed circuit board. Does that even work in the rain?

After opening and examining the parts, it all makes sense. The circuit board is actually protected by a slippery plastic-like coating. While I have not tried riding in the rain yet, just feeling the surface makes it pretty obvious that it would be OK even in wet weather.

Besides the circuit board, the other major component is the battery pack. Unlike in some similar devices, the batteries are not attached directly to the board. They rest inside a battery pack tied to the hub (the center part) of your wheel, connected to the board by a wire.

Why so complicated? This way you can have more batteries. That means longer battery life and brighter lights. As a bonus they are not spinning around in a large arc, resting secured closer to the center of the hub instead. It might sound cumbersome, but it turned out to work well in reality.


Besides the battery pack and the circuit board, there are a ton of little strips and rubber parts inside the package. At first when the little bits and pieces fall out from the package you might feel like there is a huge task ahead of you. What does this all mean?

After staring at them for a few moments, the intent becomes obvious. The circuit board has holes. You attach the circuit board to the spokes by fastening straps through the holes. The little rubbery parts go between the spokes and board so that the spokes don't touch it directly.

There is a very clear installation video on YouTube. If the video looks very long and complicated, that is only because the video presents some alternatives for accomplishing some steps, making it seem harder than it is.

All in all the installation took me around 20 minutes. At the time of writing I had also installed 5 other lights and the Monkey Light is more involved to install than some, but very straightforward. Installation was quite satisfying, as all parts make sense and connect easily. Some lights had less parts, but were more difficult to get to stay in place.

The effect

When you press the power you can select from bright mode or power save mode. There are other buttons for selecting color or type of pattern.

It's REALLY bright and yes it does actually create noticeable images in the air. 

Interestingly when you are selecting the pattern, the current selection number is shown in binary using the LEDs. I must admit that even as a programmer I'm don't find it all that intuitive to read out binary digits without having to think a bit, but it's a cute fun way to display the information. Very l33t :^)

Usually you probably won't even want to select a particular lighting pattern and can just go with the default of cycling through all of them.


Disappointingly the lights do not stop and start automatically when you start moving (as they do in some much cheaper competing products). You need to press the start button and remember to turn the lights off when you are finished. Maybe that is intentional, as the effect is so bright and noticeable that you might not always want it on even at night.

While it should be obvious, I think I should point out that you can't actually see images rendered by the light yourself when you are riding. It is purely for the enjoyment (or annoyance) of those riding around you. It's so bright I can see the flashing reflected from nearby trees and structures while riding.

About the upcoming grand finale post

I intend to eventually finish off these individual reviews with a grand finale post which tests more of these products. There are many similar Chinese products that cost less than $20, much cheaper than the Monkey Light. How will those compare? That's what I'll look into in the final review. I'm especially wanting to include a gallery to demonstrate all the different patterns these lights make.