We’ve had our 2019 Honda Ruckus for a couple of years now. It’s been neglected for more pressing projects. The thought of modifying this cool little cruiser was always in the back of our minds. You know the age-old saying, right; “Procrastination gives you something to look forward to?”

First things first, let's get familiar with this scooter's performance. At the heart of this mini machine, is a carbureted 49cc four-stroke engine which makes a whopping 4.3 HP and tops out at around 35 MPH on flat roads. Like any tiny displacement, non-turbo engine, the engine capacity limits how much power you can make and thus how fast you can go. To improve power, we need to increase the total RPM range in which the engine can operate and to install a few supporting modifications. Our goal is to hit 45-50 MPH on flat roads, so we’re solely focused on modifications that will give us the best “bang for our buck.” At least, for now.

Part 1:  “Danger to Manifold!” - Installing an RPM Gauge for Safety, and for Science

As we’ll be installing performance modifications that alter and disable the factory rev limit we need to be able to monitor the engine RPM to prevent damage. From the factory, the Ruckus doesn’t come with an RPM gauge. Adding one is a cheap and easy way to not only monitor your revs but also to identify how each modification impacts the power band. 

The Trail Tech Tach Hour tachometer is a cheap, simple, and effective tool to monitor the RPM of the engine. This specific tachometer uses a single lead attached to either a spark plug wire or coil pack, to read engine pulses. Installation on the ruckus is a snap. Remove the seat frame, the plastic floorboard, the rear half of the upper steering shaft plastic, and run the wiring along with the chassis. Wrap the tachometer lead securely around the spark plug lead. After installing the new tachometer do a test run to verify that the Ruckus is currently limited to 8500 RPM.

Part 2: “Granny Shifting” - Installing the Polini Variator and Slider Weights

The next step in speeding up our Ruckus was to install an upgraded variator. The variator transmits engine power to the rear wheel while keeping the engine in a predetermined rev-band. This Polini variator   offers a wider adjustment range than stock when coupled with aftermarket weights. If different weights are installed in the variator, it changes the rotational mass of the variator itself. This affects how slowly or how quickly the variator will spin. Since the variator transmits power to the rear wheel, you can think of this as a gear ratio change. Installing the Polini variator requires removal of the OEM belt cover, belt and old variator. While we were there, we decided to install different weights inside the variator. It’s a good idea to get a variety of weight sets to play around with. Each weight set will affect the powerband differently so it’s somewhat of a preference thing when deciding which set works for you. We opted for 5.5g Dr. Pulley  slider weights. These uniquely shaped weights allow the variator to open farther for higher top speeds. There is a right way and a wrong way to install a new variator and weights. It’s worth doing some research before attempting this for your first time. We recommend searching Youtube for “polini variator ruckus.”

After installation, a quick test ride confirmed that while top speed didn’t noticeably increase, acceleration definitely had.

Part 3: “It’s Your Fuel Map. It’s Got a Nasty Hole.” - More Air & Fuel

The third step in this journey was to get more air into the engine. This required deleting the OEM intake box and installing the new intake. Since we’ll be pulling a higher volume of air into the engine we also need to rejet the carburetor. This will give us the additional fuel we need for the increased airflow.

This process is complex and requires the removal of many OEM components, modification of existing components, and also disassembly of the carburetor. There are many great resources online that feature step-by-step instructions on how to complete this mod. We recommend searching Google or Youtube for the Ruckus rejet procedure.

Once this was done it was time for a full-speed test run to see what we gained. We cracked 40 MPH on a flat road! The new intake is definitely much louder than the OEM system and the sound is an extra benefit to the performance gained. Not to mention, the new intake looks rad! But wait, we are not done yet.

Part 4: “I Live My Life a Quarter Mile at a Time” - Disabling the Honda Rev Limiter

The final piece of the puzzle is to disable the factory rev limiter. By doing this we allow the mighty 49cc engine to rev much higher and therefore continue accelerating to higher speeds. The NCY CDI box not only disables the factory rev limiter but also advances the ignition timing for a bit of a power bump.

While the installation is relatively straightforward it’s worth noting that you will be altering factory features and electronics. The CDI box can be installed by using wiretaps, connectors, soldering; whatever you prefer. In addition, this specific CDI box disables the factory kill switch by way of its design. There are more expensive options out there that retain the kill switch feature but we chose this unit to save some dough. Once installed it’s important to monitor your RPM and ensure the engine isn’t over-revved. This can lead to engine damage, so watch those revs! 

We buttoned the Ruckus up and achieved 43 MPH on our flat test road! This is an excellent bump in power for just over $300 in modifications. While we didn’t quite hit 50 MPH, this little bike still puts a smile on our faces. And at the end of the day, that’s all that really matters. 

With a plethora of modifications available for these little bikes, you can be assured this won’t be the last you see of the 27WON Honda Ruckus.

Would you like to see 27WON make some performance parts for the Ruckus? Let us know in the comments. 

REDEFINE Powersports?
Vincent