Derestricting A 50cc Scooter Can Be Done Easily At Home
Have you ever been riding your scooter and thought to yourself: "Man, I wish this thing was faster"? I have good news, it can be. 50cc scooters have restricting devices in them to prevent them from attaining certain speeds. The legal top speed for a "limited speed motorcycle" as they're called in my neck of the woods, varies between different states and provinces. The good news is that derestricting a 50cc scooter is easy and free!
Scooters are restricted because of local laws and sometimes because of insurance rules. To be insured as a limited speed motorcycle it needs to have it's speed limited. Luckily the restrictor used to slow 50cc scooters down can easily be removed. It's nothing more than a washer and taking the time to remove it will increase your top speed and acceleration, making your scooter safer on major roads and more fun to ride.
There are 2 types of restrictors used in 50cc scooters, exhaust restrictors and variator restrictors. Some scooter manufacturers use one or the other and some use both. An exhaust restrictor limits the flow of air through the pipe keeping your scooter's engine power low, while a variator restrictor basically limits the transmission to a lower gear. I have done this to my scooters as well as read online reviews and it's the quickest and easiest way to get more power from your scoot.
Make sure to get yourself a repair manual from Honda, Aprilia, Yamaha or whatever make your scooter is prior to beginning the job. You may not need the manual but it will prove very helpful if you get stuck at any point.
Here's how to remove an exhaust restrictor:
You will need:
- Sockets and socket wrench
Start by making sure the bike is cool. Let it sit for an hour if you have ridden it recently. Remove the 2 bolts holding the exhaust pipe onto the motor. This can be difficult and require some clever maneuvering as they're usually on the bottom of the engine. Now remove the bolts holding the exhaust pipe to the frame of the bike, there are usually 2 or 3 and once they are out the whole pipe should just come right off.
Now look at the pipe right where it meets with the engine. You will see that a washer has been installed in the pipe to restrict air flow. How you remove this washer depends on how it's installed but typically they're tack welded in. What I have found is that you can grab it with needle nose pliers and twist it out. Voila, you've just breathed new life into your scooters engine.
Now here's how to remove a variator restrictor:
You will need:
- Impact wrench (pneumatic or electric is fine)
- Socket wrench and set
- Oil filter wrench (rubber strap style)
Remove kick starter and transmission cover (usually on left side of bike). The variator is mounted on the front end of the drive belt. You will then need to remove the large nut holding the variator to the bike with the impact wrench.
If you don't have an impact wrench you can do this with a socket. If you use a socket, use the oil filter strap wrench to hold the variator still while you remove the nut. Pull the front half of the variator off and there's the washer right between the two halves.
Re-assemble the variator without the washer and replace the transmission cover. Congratulations, your scooter can go faster now! Ride responsibly.
Most 50cc scooter owners don't realize that their scooters are restricted at the factory so that they can only achieve certain speeds. Following these simple steps will increase your scooter's acceleration and top speed up to 10kph more than what it was. Derestricting a 50cc scooter is a simple and straight forward project that only takes about an hour. I should also mention that if you ever place your 50cc scooter for sale, having it derestricted will make it far easier to sell and increase it's value to the buyer.