We all know that not much can separate motorcycle lovers from our bikes, and for many riders, the blazing summer heat is no exception. In fact, there is no better feeling than cooling off with a nice breeze from cruising down the road on your Harley.
That said, nothing ruins the day faster than an overheated bike. If you are planning to take your Harley out in hot temperatures, it is essential to be aware of the signs of motorcycle overheating and understand what you can do to prevent damage to the engine.
Before you plan a ride in hot weather, make sure you know a few basics about your Harley’s engine and cooling system. For example, if your bike uses an air-cooled engine, you are far better-off moving than you are idling. It is tempting to assume that that resting puts less stress on the engine, but this is a myth. Sitting in place with the bike running is one of the worst things you can do for an air-cooling engine in hot temperatures. Air-cooling engines have their virtues, such as being smaller and more affordable, on average. However, they rely on the movement of air across the engine to remove excess heat, making them more prone to overheating when stopped or moving at slow speeds. Avoid the traffic when riding with an air-cooled engine. The rush hour stop-and-go is not just annoying, it is dangerous for your bike.
We understand that you love your air-cooled Harley, and there is good reason to. Fortunately, you are not out of luck, even if you want to ride in a hot climate. If your bike struggles with overheating or routinely carries a heavy load, an oil cooling system is a lifesaver. An oil cooling system helps your bike maintain an ideal operating temperature even when the traffic lights and scorching weather are working against you.
Liquid cooling systems are the more common cooling system on most motorcycles, and they tend to perform better when it comes to temperature regulation. Liquid-cooled engines have coolant that continuously circulates around the cylinder, picking up heat from the engine as it travels back toward the radiator. The radiator then uses fans to return the temperature of the coolant back to normal before recirculating it.
To prevent overheating with a liquid system, first thing is first, check your coolant levels. The best motorcycle coolant for hot weather should have a higher ratio of water than coolant. Many motorcycle experts add distilled water and products like Water Wetter or Engine Ice to the coolant.
Secondly, make sure your radiator and fans are in top shape. Clean the fans routinely and check for leaks in the radiator and related components. Radiator leaks seriously inhibit the cooling system’s effectiveness. A great way to protect against leaks and radiator damage before it happens is to install a radiator guard. The guard blocks the radiator from being punctured by any projectiles in the road. It is better to be safe than sorry with any type of riding, but if the day’s plans include off-roading or travelling at high speed, it is especially important that you consider adding sturdy radiator protection.
A less apparent factor to consider is the age of your coolant. Older coolant breaks down over time, changing the fluid ratio and making it less productive. Aging coolant may also begin causing aluminum corrosion in other parts of the cooling system. We recommend changing the coolant every two years. It is a relatively easy job to do yourself, and the Harley owner manual should walk you through it step-by-step. Regular upkeep of your engine’s cooling system costs very little and can save your motorcycle from more serious damage in the future.
Keep It Oiled
Sure, oil is necessary to keep the engine parts lubricated and moving smoothly, but it is crucial to remember that when there is not enough lubrication, the friction increases engine temperature. On the other hand, it is also possible to have too much of a good thing. Overfilling the oil causes pressure buildup, forcing the engine to work harder and potentially damaging the gaskets and seals. Excess oil could also spill onto other parts of the bike, causing a whole variety of issues. If it is spilled on a hot surface it may begin to smoke as it burns off. To make matters worse, oil that comes into contact with moving parts of the engine, such as the crankshaft, can become bubbly and aerated. Once this happens, the oil begins to lose its lubricating properties. In any case, too much oil or too little oil often have the same effect. They create more heat, which is the last thing your bike needs. Save yourself the headache, and fill the oil exactly as instructed.
Choosing the right type of oil is just as essential. So exactly, how hot does a motorcycle engine get? Extremely hot! Motorcycle engine temperature can vary, but in normal circumstances, a Harley’s temperature should average about 160-220 degrees. If you are moving at high speeds or frequently idling, chances are good the engine is running on the hotter end of the spectrum. On days of blistering heat, the outside environment only adds to the engine’s operating temperature. Lightweight oils can quickly breakdown under these conditions, so it is wise to use either a synthetic oil or a higher weight oil that will remain thick enough to work properly even under extreme temperatures.
Aside from signs of trouble such as engine stalling or an excessively high reading on the temperature gauge, one indicator of overheating is hearing “pinging” or “knocking”. If you are unfamiliar with the noise, imagine the sound of a rock or marble bouncing around the inside of the valve train. Other noises to listen for are misfiring, sputtering or choking. You may also notice an overheated motorcycle feeling heavy or sluggish. If any of these Harley overheating symptoms occur, shut off your bike immediately, before a disaster, such as a seizing piston, wrecks the engine for good. Just as you take precautions when preparing your body for extreme temperatures, you ought to do the same for your Harley. Knowing how to keep your engine cooler on hot days with affordable DIY protection and maintenance can help your bike on stay on road for many more miles.