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Are you having a tough time trying to decide between an air-cooled and liquid-cooled motorcycle?
The decision doesn’t come as easy as one might think, and it’s always helpful to look through some valuable information that can help you better decide on what one to go with.
TL;DR: Air Cooled vs Liquid Cooled Motorcycle
Air Cooled Motorcycle
Liquid Cooled Motorcycle
Best for those who don’t want to spend time maintaining their motorcycles.
Best for commuting, keeping your carbon footprint low, and driving in the heat.
What is an Air-Cooled Motorcycle?
Lowering the heat generated by combustion is a critical factor in achieving stable engine efficiency. This occurs in two ways: by air cooling or by liquid cooling.
Air-cooled engines remove heat from the motorcycle through the air that comes in contact with the engine as you’re driving.
You’ll notice that motorcycles have fins on the sides of them. The objective of those fins is to make more surface area so that the air can pass through them. Air cooling is a straightforward method of cooling.
There aren’t any specialized parts of gadgets that make air cooling possible, and that’s why it’s still sticking around. The cooling fins on a motorcycle are designed to add aesthetic appeal to a motorcycle, which is a selling point for some people.
What is a Liquid Cooled Motorcycle?
With liquid cooling, you’re using water-based liquid to keep the engine running cool. The liquid used isn’t just water. The coolant will typically have alcohol in it so that oxidation, rusting, and freezing don’t occur.
Passages into the engine allow this liquid to freely circulate. The coolant will go through the radiator to reduce the temperature levels, and then it is circulated all over again.
Liquid cooling is a little more difficult to understand than air cooling, but both cooling methods will effectively cool down a motorcycle.
Motorcycle Cooling System - How It Works?
Machinery that has internal combustion will require a method of cooling to prevent it from overheating. Because motorcycles have internal combustion, they require either air cooling or liquid cooling. The better a motorcycle operator understands how cooling works, the higher chances they have in preventing any costly repairs.
Even though the cooling system on motorcycles seems pretty straightforward, there can be detrimental consequences if the cooling system fails to function how it should.
Air Cooled Motorcycle Engine
An air-cooled motorcycle engine is the easiest type of cooling method to understand. When it’s a warm summer day, and you need to cool off, you might stand in front of a fan to cool your body temperature down.
This is the same way a motorcycle cools off. An air-cooled motorcycle will have fins that allow the wind to pass through it more efficiently. The internal combustion chamber in a motorcycle runs extremely hot when it is in use, and it has to run hot so that the engine can get the pistons to propel up and down.
If the engine gets too hot, parts of the engine can begin to deteriorate and break down. If you’ve ever heard someone say that they have a seized engine, that means that the pistons inside the engine have melded against the cylinder walls. Seized engines usually occur when the temperature inside the engine has gotten too hot.
It isn’t much you can do when your engine seizes. It’s usually cheaper to get an entirely new engine installed, which brings us back to the fins of the motorcycle once again. The motorcycle fins are positioned so the air deliberately focuses on the cylinder of the engine.
Fins are usually constructed out of aluminum because it’s a lightweight material and is effective at transferring heat. When you’re driving your air-cooled motorcycle, the wind will move through the fins and keep the motorcycle at a cooler temperature. If your motorcycle didn’t have those fins, it would overheat much quicker.
Liquid Cooled Motorcycle Engine
Liquid cooling is another way that motorcycles can cool down, but it works a little differently than air cooling. Liquid-cooled motorcycles are built a little differently than air-cooled ones. With liquid-cooled motorcycles, you’ll notice that they don’t have fins anywhere on them.
They’ll instead have a radiator built into them, typically located near the front of the motorcycle. Liquid-cooled motorcycles are a little more complicated than air-cooled ones, and they are also more effective in climates with extreme temperatures.
Where air-cooled motorcycles have fins on them, liquid-cooled motorcycles will have water jackets located inside of the engine and near the cylinders. A radiator and reservoir are attached to the trails.
A liquid-cooled motorcycle will have a water pump inside that will propel liquid from the water jackets to the radiator and then back to the engine. When the liquid circulates, it’ll go through plates that will keep things even cooler because of the wind that passes through.
Once the liquid cools down after going through the plates, it’ll then be circulated back through the engine to ensure everything stays nice and cool.
Liquid-cooled bikes have a thermostat that will sense when the engine temperature is getting too hot. If the engine gets too hot, the thermostat will sense that and then begin to regulate the amount of coolant getting to the engine.
A fan near the radiator will turn on if the coolant isn’t doing its job to keep the engine as cool as it should be.
Liquid-cooled motorcycles are also commonly referred to as water-cooled, but it’s not entirely just water passing through the motorcycle. The water is mixed with an antifreeze solution. Antifreeze is used because it’s more tolerant to hot and cold temperatures.
Relevant Characteristics Between Air Cooled and Liquid Cooled Motorcycle
Air-cooled and liquid-cooled motorcycles have different characteristics that make each of them unique. As to the cost difference between them, liquid-cooled motorcycles are more expensive because there are more moving parts involved in the manufacturing process.
Liquid-cooled motorcycles have a higher heat tolerance because of their more complicated circulation system, and that means they’ll be able to withstand a lot more heat exposure.
Air Cooled Motorcycle
Liquid Cooled Motorcycle
High - 155F / 68C to 220F / 104C
Replace coolant every 10,000 miles
Similarities and Differences
There are a variety of similarities and differences between air-cooled and liquid-cooled motorcycles.
Air Cooled and Liquid Cooled Motorcycle Differences
Air-cooled motorcycles don’t use a liquid-based circulation system when cooling down a motorcycle. Air-cooled motorcycles don’t have hoses, a thermostat, or a radiator, making it much more straightforward if you ever need to repair something.
Fewer parts in a motorcycle mean that there is a lower chance of things breaking down, which also means that air-cooled motorcycles can be seen as more reliable than liquid-cooled motorcycles. The maintenance required is often much lower because you also don’t have to add coolant to air-cooled motorcycles.
Air-cooled motorcycles are known to be cheaper than liquid-cooled ones. This is because they are easier to manufacture in comparison, and that cost saving is passed onto the customer when it comes time to purchase the bike.
Another big difference between air-cooled and liquid-cooled motorcycles is the performance of them. The acceleration of liquid-cooled motorcycles is known to be much more reactive than air-cooled ones.
Air-cooled motorcycles do not provide as much power output as liquid-cooled motorcycles because the more power output, the hotter the engine will get.
Air-cooled motorcycles use the wind to cool down a bike, whereas liquid-cooled motorcycles use a liquid circulation system.
Because air-cooled motorcycles rely on the air to keep them cool, it results in having less control over the temperature that motorcycles get up to.
The performance of liquid-cooled motorcycles is much higher than air-cooled ones. Liquid-cooled motorcycles have much greater control over the temperature levels, meaning more reliability in many different climates.
Air Cooled and Liquid Cooled Motorcycle Similarities
The main similarity between air-cooled and liquid-cooled motorcycles is that they are both designed to keep the motorcycle cool, but they just use a different approach to fulfill that end goal.
Benefits of an Air-Cooled Motorcycle Engine
- Air-cooled motorcycles are very easy to maintain because they don’t have a thermostat, radiator, or hoses. Fewer parts in the motorcycle mean that there is a lower chance of things breaking down.
- Air-cooled motorcycles are cheaper to purchase in comparison to liquid-cooled motorcycles. Because fewer parts need to be installed, customers can enjoy some added cost savings.
- A lot of cruisers use air-cooled engines because people drive them on highways at higher speeds.
Benefits of a Liquid Cooled Motorcycle Engine
- Liquid-cooled motorcycle engines have more reliable cooling, making them a better option when temperatures get too extreme levels. If you’re driving on a hot day in a busy city with a lot of stop-and-go traffic, an air-cooled motorcycle engine will heat up a lot faster than a liquid-cooled engine.
- They are known to produce less noise than air-cooled motorcycles. Whenever you’re driving in a busy city, you’ll always hear that cruiser driving by and making a ton of noise. Cruisers typically have air-cooled engines.
- There is less pollution with liquid-cooled motorcycle engines. This can be another benefit for those that like to keep their carbon footprint to a minimum.
- Liquid-cooled motorcycle engines are much better for sportbikes and performance bikes.
What About Oil Cooled Motorcycle Engines?
An oil-cooled motorcycle engine is an air-cooled motorcycle engine that also has an external oil cooler in it. Some manufacturers will call it an oil-cooled engine to make it easier to tell the difference between them.
How Does It Function?
In an oil-cooled motorcycle engine, the oil circulates throughout the engine in an oil tube connected to an external oil cooler. There are capillary tubes connected to the oil cooler, and around the oil cooler are fins.
Engine oil circulates through the capillary tubes, and it reduces the heat because the air blowing in through the fins located near the oil cooler. As you’re driving your motorcycle, the increased volume of air passes through the fins and lowers the temperature.
Engine performance is increased, and there aren’t as many moving parts of oil-cooled motorcycle engines when compared to liquid-cooled ones. Oil-cooled engines are usually used on smaller motorcycles and some cruisers.
There are a couple of factors to consider when looking at the heat dissipation of oil-cooled motorcycle engines:
- How much surface area is involved between the oil cooler and the air
- How much airflow is involved
- How well the metal oil cooler is conducting with the heat
Oil coolers sit in front of the engine of the motorcycle. As they are in the front of the engine, the air flows right up through it to reduce the heat. The oil cooler will also have fins attached to it, and that will even further increase the amount of air getting to the engine.
The more surface area that comes in contact with air, the higher chances that heat will be dissipated. More airflow means better temperature control.
What Are Some Advantages of Oil Cooled Engines?
- Simple design
- Not many moving parts
- Straightforward to manufacture in comparison to liquid-cooled engines
- Lighter than liquid-cooled engines
- Not much maintenance required
What Are The Disadvantages of Oil Cooled Engines?
- The efficiency of the engine could be affected
- Not very good for multi-cylinder engines
Factors to Consider When Choosing Between an Air and Liquid Cooled Motorcycle
There are several things to keep in mind when considering going with an air or liquid-cooled motorcycle.
If you want a quiet motorcycle that doesn’t cause everyone around you to wonder where that loud noise is coming from, liquid-cooled motorcycles are the better choice. Air-cooled motorcycles tend to be noisy, and you’ll always look twice when you see a cruiser driving past because of how loud it is.
Air-cooled motorcycles don’t have as many parts as liquid-cooled motorcycles, and that means that the overall maintenance required will be much less. If you want a low-maintenance motorcycle without having to worry about coolant levels, air-cooled motorcycles are a wise choice.
Air-cooled motorcycles tend to be less expensive than their liquid-cooled counterparts, so if you’re on a budget, you might want to stick with air-cooled motorcycles.
Liquid-cooled motorcycles run better in all different climates. If you’re in a hot climate and living in a city where you’ll be driving through heavy city traffic scorching hot summer days, you might be better off going with a liquid-cooled motorcycle.
Liquid-cooled motorcycles leave lesser emissions behind when driving, and that means a lower carbon footprint. If you’re an environmentally conscious person, you might want to stick with a liquid-cooled motorcycle.
If high-end performance is the reason why you’re purchasing a motorcycle, then going with a liquid-cooled engine should be your choice.
Repair costs for air-cooled motorcycles will be cheaper than liquid cooled ones. The general rule of thumb is to replace coolant around every 10,000 miles. Some people do it sooner than others, but it’s always good to replace it on a routine basis.
Making the final decision to go with an air-cooled or liquid-cooled motorcycle will be dependent on a couple of questions that you should ask yourself before finalizing your purchase.
Do you want a high-end performance motorcycle? If the answer is yes, then you should get a liquid-cooled motorcycle.
Do you want a quiet motorcycle? If the answer to that question is yes, then you’ll be better off going with a liquid-cooled motorcycle.
Do you want a motorcycle that is lower maintenance and cheaper to purchase? Air-cooled motorcycles don’t require as much ongoing maintenance as liquid-cooled motorcycles. They are also cheaper to repair and don’t come with as many parts.
After answering these questions, you should get a better idea of what kind of motorcycle you should be gravitating towards.
People Also Ask
Here are some of the questions people commonly have about the topic.
Does a Liquid Cooled Motorcycle Engine Work Well in the Winter?
A liquid-cooled motorcycle will perform better on both spectrums of temperatures. Outdoor air doesn’t affect a liquid-cooled motorcycle engine as much as it does with an air-cooled one.
Do Air Cooled Motorcycles Overheat?
Air-cooled motorcycles have a higher tendency to overheat than liquid-cooled motorcycles. Air-cooled motorcycles rely directly on the airflow passing through the fins as you’re driving. If you’re driving on a hot summer day in the middle of a city with a lot of stop-and-go starting, then you run a higher risk of potential overheating.
What Temperature Does An Air Cooled Motorcycle Engine Run At?
Air-cooled motorcycle engines typically run at a temperature range between 230-250 degrees celsius.
Is Synthetic Oil Good For Air-Cooled Engines?
Synthetic oil is good for providing lubricant to air-cooled motorcycle engines. There is less friction, cooler engine temperatures, and reduced engine wear and tear with synthetic oil.
Which Is Better, an Air Cooled or Liquid Cooled Motorcycle?
There isn’t a clear-cut answer to which specific type is better because it all boils down to what you want out of your motorcycle. If you want a cheap, low-maintenance motorcycle to boot around on now and then, then you might be better off with an air-cooled motorcycle.
If you’re looking for a quiet motorcycle, don’t want to leave a large carbon footprint behind, and have good performance in a wide variety of climate conditions, then you’ll probably be better off with a liquid-cooled motorcycle.