There’s a lot of debate in the go-kart world over the best way to make a kart turn. Some people swear by live axles, while others prefer differentials. So what’s the difference between live axle vs differential? And which one is better? Let’s take a closer look.
Live axle vs. differential – Mechanism differences
Let’s start with the basic differences – how do they work?
How Does A Live Axle Work?
A live axle is a simple design – it’s just a solid shaft with driven wheels at the ends. The torque is transferred from the engine to the sprocket (using a chain or belt), which directly turns the axle and the wheels.
This design allows both driven wheels to spin at the same speed. This is the major disadvantage of the live axle that we will discuss in the next section.
Basic components of a live axle include:
- Shaft – supports the weight of the vehicle and turns the wheels
- Bearings – allow the shaft to spin freely
- Sprocket – connects to the engine and turns the axle
- Chain/belt – transfers torque from the engine
- Brake disc
How Does A Differential Work?
When your car takes a turn, the outer wheels need to spin faster than the inner wheels (because the route is longer.) Otherwise, the car would simply skid around the corner.
That’s why the differential is used in most cars.
A differential contains a driveshaft (input) and two outputs connected to the drive wheels. The rotations of the drive wheels are then coupled to each other by their connection to the roadway.
The main disadvantage is that a differential needs all four wheels to touch the ground. Otherwise (your car gets high-centered, stuck in mud or ice), it will not work. Many off-road vehicles and drift cars use a locked differential, which forces the wheels to rotate at the same speed, making it similar to a live axle.
Live Axle Vs Differential – Pros and Cons
A live axle can’t handle corners well because the outer wheel needs to spin faster than the inner wheel. This leads to a technique in kart racing- lifting. When you go into a corner, the inner rear wheel needs to be lifted off the ground so that it doesn’t make contact with the road.
The “lifting” is often not visual, especially in wide tracks. And sometimes, all it takes is reducing the load on the inner wheels while increasing the load on the outer wheels. Doing this will give you sharper cornering. The downside is that the outer wheels will wear out much faster because they have to do all the work.
A differential can take corners a lot better because it can split the torque between the two driven wheels. This will allow the wheels to spin at different speeds, which is essential for cornering.
Weight and design
A live axle is much lighter than a differential. This is because live axles don’t have such complex gears.
As you already know, weight is the enemy of speed. Therefore, live axles are a better choice in small vehicles because they can save a lot of weight.
In bigger vehicles, something like your passenger car always uses a differential because the weight isn’t as much of an issue, but safety is.
The “weight” section leads us to another aspect- energy efficiency.
A differential is not efficient as a live axle!
Weight is the first answer to the question “why.” The more weight you have, the more energy is needed to move it.
The second answer for this is friction. Because the differential has more gears, it creates more friction as the car moves. This means that you lose energy going straight or in a corner. In the live axle case, you only lose more energy when turning.
A differential needs more maintenance than a live axle. This is because the gears need to be oiled and cleaned regularly. If they’re not, the gears will start to grind and wear down.
The same thing is applied to the live axle. However, the complexity and cost of the live axle maintenance process are much lower.
Of course, a differential is much more expensive than a live axle. This is because the differential itself is more plex, and other related components are needed to make it work correctly.
For example, the live axle setup only needs one brake disc and caliper, while the differential setup needs two brake calipers at each drive wheel.
Moreover, it’s also about the time and effort that goes into the setup and maintenance. A differential needs more care to be properly taken care of.
Which one should you choose?
This may be the most important question if you’re trying to build a go-kart. The answer is, that it depends.
If you’re going to do a lot of off-roading or drifting, then a live axle is the better choice. If you’re just going to drive on an even firm street, then a differential is what you need.
In case you’re building a competitive racing kart, a live axle is always the way to go as it minimizes the power lost by having lighter weight and less friction.
Remember, both setups have pros and cons, and it ultimately comes down to your driving style and preferences.
Closing It Up
Now, I hope I’ve covered everything you were looking for about “Live Axle vs Differential”. If you still have any doubts or questions regarding this topic, leave a comment below I’ll definitely reply. If you liked it, then share this with your friends.
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