Starter Parts and Upgrades Guide
Currently your bike is somewhat running or you can't get it running at all, let's start with that.
Replacing the Carburetor
The stock carburetor is very cheap and often can be hard to get running if at all, especially with all the emissions equipment. The recommended carburetor to replace the stock one is a Chinese Mikuni VM22 or a Nibbi 22. This is extremely simple and just requires a few bolts to be removed and the fuel line to be disconnected. Once the new carburetor is installed, you will need to adjust the air/fuel mixture and the idle screw. You may also need to adjust jetting sizes as well as the needle height. This is often the trickiest thing to get exact, the biggest factors in tuning the carburetor is your elevation and weather. The bike should accelerate smoothly from low RPM all the way to high RPM. Any surging or backfiring or anything strange is a sign of a bad tune. Don't forget a new petcock as well, as the factory carburetor has it built into it. This will also allow you to replace the inline fuel filters easily. Check out the "Tuning the Carburetor" guide for more information.
Nibbi 22mm Carburetor for 125cc
Carburetor upgrade for more power and throttle response.
$62.00
Buy on Amazon
Adjusting the Clutch
The factory clutch cable is very poor in quality and is the main culprit of not having a smooth pull and trouble finding neutral and shifting. These bikes have a couple points of adjustment. The main point of adjustment is behind the clutch side case, behind the branding logo of the bike. These sometimes can be really hard to remove, do not strip them, you might need an impact screwdriver. I use this one below to break stubborn screws off. Once inside you will see the actuator and the nut that holds the lever. You want to adjust the nut to where there is a little bit of play in the lever. Check the Clutch Adjustment Video for a visual guide. Be sure not to lose the pin that holds the actuator in place, it is very small and can be easily lost. Make sure to get this adjustment right first before adjusting the cable. To test the clutch adjustment, start the bike and put it in first gear. If the bike jumps forward and dies the clutch is not engaging enough. If the bike won't go into gear, the clutch is also not engaging enough. This is the main reason why people say these bikes are hard to shift and find neutral. To further test this, shift the bike into first gear and hold the clutch in, then rev the bike. If the bike revs up and doesn't move with the clutch fully engaged, the clutch is now engaging properly. you should now find that shifting and finding neutral is much easier. Now we must also work the other direction as well, as we want the clutch to fully disengage when the lever is released. We don't want the bike to slip the clutch. You should be able to now put it in 1st gear and slowly release the clutch and the bike should move forward. Understand that if you are releasing the clutch lever right at the end of the lever's travel, the clutch clutch might not be fully disengaging. You can adjust the cable at the lever to make some smaller changes, you can also make some small changes at the actuator with the adjuster nut that expands and contracts the cable length. This should completely resolve the main complaints from people saying these bikes are hard to shift and find neutral.
Shifter and Clutch Cable Upgrade
Another common complaint is the shifter and its linkage type design. Upgrade to a simple folding shifter allows for a much smoother and more precise shifting experience. The Tusk Shifter below fits perfectly and is a great upgrade. Also to get a much smoother pull and better feel, the clutch cable can be upgraded to a Honda Grom clutch cable. This is a direct fit and is a much higher quality cable and not as prone to splitting and fraying. Buying from your local Honda dealer is the best option.
Honda Clutch Cable
Honda Grom clutch cable upgrade for smoother pull. Part Number 22870-K26-C01
$10.00
Buy on AmazonIntegrated Tail Light and Fender Eliminator
The most popular initial upgrade is the integrated tail light and fender eliminator. For the fender eliminators, there are a few options, but the most popular ones are the fixed and adjustable ones below. For tail lights, the smoked integrated LED tail light is the most popular and the only one that i recommend. There are a few others that exist in a couple different styles, but they are dangerously dim and often very hard to tell if you are braking or not. The smoked integrated tail light is very bright and is a direct fit, you will just need to do some simple wiring, as none are plug and play. This integrated tail light has turn signals built in and for the price, it is a great upgrade. After almost 3 years of use, I had a small issue with a portion of the LED's, but for the super cheap price, I can't complain and just bought another one.
Fender Eliminator Fixed
Sturdy metal, good for reusing stock license plate light and rear turn signals.
$20.00
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Fender Eliminator Adjustable
Cleaner look, best for integrated turn signals. Adjustable with included LED plate light.
$30.00
Buy on AmazonChanging The Levers
The stock levers are very cheap and often break in any sort of drop. The most popular levers are the adjustable ones below. These are a direct fit and are a great upgrade. These are also available in a few different colors. The clutch side may need a little bit of filing to fit properly.
Changing the Battery
The factory battery on these bikes can be fairly weak and often die sometimes after a couple months. Spending a couple bucks on a cheap battery upgrade is a great idea. This battery I run on all my bikes and have had no issues with them at all.
Performance Upgrades
Now after these initial modifications, you can start to look into performance upgrades and other drivetrain upgrades. Check out the Performance Upgrades guide for more information.