Does a Scooter Have a Clutch?

Commuting electric scooters have become the go-to trend these days when it comes to going to and from work, and with good reason. They are fast, nimble, easy to park, and when you are done with them you can simply leave them be for the next person to use. They also offer great value for money when you think about the amount of fuel you would pay when using a car.

Speaking of cars, we know there’s really no comparison to be made between riding a scooter and driving a car. While 2-wheeled vehicles are more adaptable and can get you out of jammed situations, a car is always a good thing to have for a long trip. If you’re curious about what exactly a scooter is and whether it has car-ish things like a clutch, keep reading to find out.

Differences between scooters and motorcycles

It’s a proven fact that people will ride on just about anything. Therefore, a number of vehicles have been invented to cater to all types of necessities. Traditionally, a scooter can be defined as a style of a two-wheeled motor vehicle which has several unique characteristics such as a step-through frame and an engine located below the rider and to the rear.

Furthermore, scooters tend to have smaller wheels, typically less than 16” in diameter. Any motorcycle wheel usually goes above that number, so there’s one difference right there. Motorcycles also have an engine mounted in the middle of the frame and the gas tank that they use is located above it. Therefore, the rider will sit astride the engine and above the gas.

A scooter will usually have the engine installed as part of the rear suspension, while on motorcycles it will be attached to the frame. There’s a big difference here, as when a motorcycle rear wheel goes up and down the engine will remain stationary, compared to a scooter where the whole engine and transmission will move with it.

Coming closer to the central question of our article, we have to say that 99% of scooters these days have a so-called CVT automatic transmission, also known as a “twist and go”. What this means is you don’t have a clutch to control and gear changing is automatic. The same percentage of motorcycles will come with a manual clutch where you shift with your foot.

The braking system is also quite different. On most scooters, you apply the rear brake with your left hand while motorcycles use the right foot for the same thing. Now and again, you will find some manual scooters or some automatic motorcycles but keep in mind those are very much the exception, rather than being the rule.

These differences also create an overall different feeling when riding the two types of vehicles. A motorcycle will usually have better acceleration and special high-speed handling characteristics while a scooter will be much easier to maneuver at low speeds, better to wiggle your way in traffic and easier to ride for novices.

CVT 101

As we said, most motor scooters work with something called CVT or “Continuously Variable Transmission”. They are praised for delivering a smooth riding experience and also improving fuel efficiency. The question is, with no fixed gear ratios to control them, how exactly do they work?

In a nutshell, a CVT does not offer those fabled fixed gear ratios but rather what it does is it allows the vehicle’s engine to choose the most efficient revolutions per minute for a range of speeds, including the one it has at that exact moment.

The most obvious way in which CVT can be useful is ensuring maximum fuel efficiency. In the following, we want to continue by explaining in plain English how it works and why scooters are not really at their best when used with a clutch.

Normal automatic gearbox

A normal automatic gearbox uses gears to help with matching engine speed to road speed. When you are riding at a low speed, the engine will turn a small gear which is connected to a larger gear and will turn the wheels with the help of other components.

At higher speeds, you will see the exact opposite. The engine will turn a large gear connected to a small gear, so this time it is the small gear that will turn multiple times. Smoothing out the gearchanges and making them faster is one of the main challenges that automakers have to deal with. Even with modern cars, nine gears is still the maximum and most only have six.

The standard automatic gearbox is somewhat at disadvantage because of this, due to the limited number of gear ratios the engine has. Considering that engines are best optimized to run in a quite narrow rev range, the wider it becomes, the harder this gets. Even though there are lots of technologies to help engines run smoothly, the fundamental problem is still there.

Why is CVT better?

Enter the continuously variable transmission to solve all the issues. Their design completely gets rid of the old gear system, instead opting for two pulleys connected by a belt. While running, the engine turns one pulley while the other one remains connected to the rest of transmission and further on to the wheels.

The magic in this solution is the fact that the size of the pulleys can change from small to large and anything in-between, therefore completely obliviating the regular automatic gearbox’s issues.

In plain English, the engine’s pulleys will be different when you start, one small and one large. As the car gathers speed, the engine’s pulley gradually reduces in size in perfect unison with the other one increasing in size. Basically, you’re changing gears every second and the engine goes directly to the best rev range for each situation.

How does this work with scooters?

First of all, scooters are made for comfortable traveling at low speeds so having to constantly change to first and second speed would not guarantee this. The clutch is used to disconnect the engine from the wheels and during the time you are reconnecting it, you can’t use the gas and you can’t brake.

While this might not be an issue in a car as people usually change gears quickly and, even if you hit something, you’re still in a car and won’t probably be injured, the same does not go for scooters. Losing control for a quick second can be a difference-maker when you are darting in and out of traffic.

If you’ve never ridden a modern scooter before, the sensation will feel quite odd at first, because it may feel like something is wrong, especially for people who are used to riding motorbikes. Since the way the transmission works is quite different, scooters do not have to worry about the motor’s rotations to increase and decrease speed.

In practice, what ends up happening is as you twist the throttle the sound you hear will not change yet the speed will still increase. Considering a motorcycle’s famous sound when accelerating, the lack of this in scooters might scare some newbie riders away. What’s really happening is CVT doing what CVT does and we should all be grateful for it.