No, you generally cannot use motorcycle oil for a car. Motorcycle oil and car oil have different characteristics in order to solve specific problems and accomplish different things. As a result, using motorcycle oil in your car can result in lowered performance and even damage.
What’s the Difference Between Motorcycle and Car Oil?
Motorcycle Oil Lubes the Clutch
The main difference between motorcycle and car oil is that motorcycles usually use oil to lubricate the gearbox and sometimes to cool the engine, not just to lubricate the engine.
This is the case if you have a motorcycle with a “wet clutch” and a “liquid-cooled” engine.
Read: Best wet clutch oil
As a result, motorcycle oils have a much higher viscosity than car oils, and they produce more friction, which helps the clutch operate correctly.
Car oil, on the other hand, is designed to be as frictionless as possible and often has “friction modifiers” to reduce friction even further.
Motorcycle Oil Takes More Punishment
Most motorcycle engines reach higher revolutions per minute and hotter internal temperatures than car engines. Motorcycle motor oil is designed to withstand these conditions, and that equates to a viscosity and thickness that may not be appropriate for a car.
Car Oil Has More Detergents
Although detergents are present in both car and motorcycle motor oil these days, car oil tends to have a much higher concentration of them.
The purpose of these detergents is to prevent dirt and grime from accumulating in the oil. Instead, the detergents attract these particles so that they float to the top and are removed by the oil filter.
What Could Happen If I Put Motorcycle Oil in a Car?
Reduced Fuel Efficiency
Best-case scenario, your car will continue to run just fine with motorcycle oil but will experience a reduction in fuel efficiency. This is simply because the higher viscosity and friction of the motorcycle oil make it more difficult for the engine to move the pistons, so it uses more fuel.
One of the reasons motorcycle and car motor oil are so different is that cars have long been subject to emissions regulations that haven’t applied to motorcycles.
As a result, car manufacturers have focused on engine efficiency over performance, reducing friction and limiting emissions.
Again, your car may actually continue to run with motorcycle oil, but it won’t be as efficient and will produce more emissions. This could result in a failure at an emissions inspection.
Because motorcycle oil can cause the engine to operate under higher friction than it’s designed to, it might not work in sync with the transmission. This could result in transmission lockup and damage that might prevent your car from running altogether.
But Can I Use Car Oil for a Motorcycle?
No, definitely not. Using car motor oil in a motorcycle is even worse than the reverse. If your motorcycle has a wet clutch, it needs the oil not only to lubricate the gearbox but also to provide a certain amount of friction. Car oil doesn’t provide that friction, which can lead to clutch slip.
More importantly, since car oil is thinner, it doesn’t protect a motorcycle’s engine from the high revolutions and temperatures. Long-term use of car oil in your motorcycle’s engine could damage it.
If you’re unsure whether an oil can be used in your motorcycle, aside from reviewing your owner’s manual, you can also check if it has a JASO rating. JASO stands for the Japanese Automobile Standards Organizations, and they give the following ratings to oils suitable for use in motorcycles:
- JASO MA2: The most recent rating, this reflects an oil suitable for use in motorcycles with catalytic converters.
- JASO MA: The original rating signifying that the oil is suitable in motorcycles where the engine, clutch, and gearbox use the same oil.
- JASO MB: This rating represents an oil suitable for motorcycles that use separate oil for the engine, clutch, gearbox, and dry-clutch motorcycles.
Some Dry-Clutch Motorcycles
Occasionally, some older, usually large, dry-clutch motorcycles will work fine with car motor oil. These are few and far between, and if your motorcycle is relatively new, it’s unlikely to be one of them. As always, check your owner’s manual or consult a mechanic.
In most cases, a car or motorcycle will still run if you put oil from the other in it. It may just lead to poorer performance or damage after long-term use.
As a result, if you’re really in a pinch, you can put motorcycle oil in a car or vice versa. However, as soon as you have the opportunity, you should change the oil to the correct one.