Using a Car Tire on a Motorcycle: Riding on the Darkside

What Is a Darksider?

IA darksider is a motorcyclist who adheres to the method of using car tires on their bike instead of traditional motorcycle tires. If you’ve ever come across a darksider, you know that they are deeply passionate about the benefits of car tires in place of bike tires. The idea is that car tires are not only more cost-effective than motorcycle tires. Darksiders also believe that car tires last much longer than motorcycle tires will.

Sounds simple, right?

Not so much. Some darksiders believe that motorcycle companies purposely manufacture their tires to fail faster, so that consumers will have purchase new ones more often. Dark siding originated with groups of bikers who enjoyed luxury touring and continuously experienced motorcycle tire failure.

From bad handling and blowouts to tire delamination and extreme wear, these bikers had enough. So, they decided to turn to car tires as an effective solution.

The Debate

The debate regarding car tire on a motorcycle is fairly heated and not likely to subside anytime soon. To delve into the debate further, it is vital to first understand some primary points.

Motorcycle tires are an integral part of any manufacturer's designs for the bikes they produce. Tires are not an afterthought, nor are they a dispensable feature that you can switch in and out as you wish. Manufacturers look at the entire design system, including how the wheels operate in congruence with the frame, swingarm, and forks.

Altering just one aspect of these components could impact the performance and function of the bike. Each motorcycle has its unique tire specifications designed for the machine and tested to ensure they perform well with the specific product.

If you deviate from the intended design by installing a car tire on a motorcycle, this could potentially affect how the bike runs. The change could also impact the overall riding safety of the machine. As such, motorcycle manufacturers encourage riders to use the tires designed specifically for their bike, rather than testing out various types of car tires.

For instance, manufacturers such as Gold Wing and Honda have established set tire guidelines, including tires that they approve for their motorcycles. These companies always recommend that you check out the owner’s manual when deciding what tires to purchase.

On the other side of the spectrum are darksiders, who insist that using car tires instead of the ones the manufacturer's recommend provides numerous benefits. Darksiders state that they enjoy more extended tread and incur less expense with car tires.

No matter what side of debate you are on, here’s what you need to know about the differences between car and motorcycle tires. If you’re thinking about going to the dark side, it’s essential to understand these differences and how they could impact you on the road. 

Car vs. Motorcycle Tires: The Differences

Car tires and motorcycle tires handle the wear and tread very differently. Whether you have a 3 wheel motorcycle or a 2 wheeler, the tread and impact isn’t anything like that of car tires. They have a different design profile and construction. These tires also have different compounds.

Motorcycles are single-track vehicles. When you operate your motorcycle on a turn, it leans into the turn. Car tires have a flat design and even contact patch that doesn’t change much in terms of size or shape when you turn a corner. Motorcycle tires have a profile that is U-shaped, which means that the contact patch changes in shape and size as you turn.

Motorcycle tire manufacturers design their products to have an even contact patch on a turn. Whereas a car tire is fat and flat when standing upright and narrows when you turn your vehicle.

The reason that car and motorcycle tires are so different is that motorists use them for various purposes. For example, passenger car tires can't withstand the same level of shock at high camber angles that a set of motorcycle tires does.

When you operate your motorcycle at high camber angles with a set of car tires, this could undercut their durability. Continuous strain on the tire’s durability could then cause the tires to fail.

Naturally, this is just one example of the departure between motorcycle tires and car tires. That’s just the tire profile.

Besides the different profiles of car and motorcycle tires, both tires have dissimilar sidewall stiffness. A tire’s sidewall is a suspension that gives rigidity so the tire can withstand the strain of cornering. When a motorcycle is vertical, the machine’s suspension system is responsible for keeping the tire aligned with the ground and monitoring the ride.

When you learn your motorcycle in a turn, the tire suspension is more relevant than the mechanical suspension. A motorcycle tire’s design is geared specifically for this type of usage, which means it can withstand tough cornering.

Another point to take into account is the fact that the majority of modern bike tires feature many rubber compounds. The tires have harder compounds in the middle to enhance tread on the highway and soft compounds at the edges to enhance grip when you lean your bike.

Car tires have a single compound. They are not designed for you to learn them over. Likewise, car tires are not equipped to deal with camber forces. 

What’s Does It All Mean?

It is true that using a car tire instead of a motorcycle tire in your bike may not have immediate consequences for regular riding. However, when performance is your main focus or an unexpected threat appears in the roadway, you could find yourself in a pickle.

A motorcycle featuring car tires rather than the tires it was designed to carry will not react the same way when you need enhanced traction. Car tires also won’t provide the precise handling you may need for a sudden stop or turn on a steep corner.

You may experience increased performance in the short term by using car tires on your motorcycle, but the potential compromise to your overall riding safety may not be worth that small advantage. 

Is It a Bad Idea to Put Car Tires on a Motorcycle?

If you’re thinking about making the switch from motorcycle tires to car tires on your vehicle, here’s what you need to know.

The contact patch a motorcycle features is considerably larger than the contact patch on a car. If you run into wet weather while you’re out on the road, the water won’t dissipate as quickly and could affect overall traction. If this continues, this could put you as the rider in considerable danger.

If you like to go to track days with your bike, you will need to give extra care to the tires you choose. Always look at your manufacturer’s manual or check with the manufacturer directly to see what the best tires are for that specific track. You could also speak with local bikers at the circuit to see what they recommend.

In the short term, putting car tires on your motorcycle may not impact your performance or your safety. However, for long-term use and safety, there could be a higher level of risk.

If you’re trying to extend the longevity of your tires at the track, you should never try to flip the tires around when they wear out on one side. Switching the tires around could be very dangerous.

Why is this?

Motorcycle tires have a unidirectional design, which means that they are supposed to rotate in a single direction. You could get into a serious accident if you flip them around, because the material could peel and loosen the tread. Eventually, the tread could even come off. 

Putting a Car Tire on a Motorcycle

Whether you have used motorcycles or new, it’s vital to know how to change your tires. If you’re uncertain about the process, it may be best to hire a professional to make the switch. Here’s what you need to know to change out your motorcycle tires for car tires (or any tire for that matter). New tires will cost $80 each on average. 

Supplies

First, you’ll need the following:

• Rim protectors
• Bead breaker
• Tire irons/spoons
• Tire paste or a solution of soap and water
• Air gauge
• Valve stem remover
• Air compressor
• Tools to remove the wheels from your bike (which will depend on the model) 

Top Tips

If you have a large motorcycle with tubeless tires, it may be in your best interest to have a professional change your tires instead of doing it at home. You will need a particular set of tools and plenty of elbow grease with tubeless tires, primarily to break the bead.

If you make a mistake, you will need new rims.

Also, you will find that it’s easier to work with the tires then they are warm instead of cold. If you’re changing your tires during the colder months, you may want to bring the wheels indoors so they can warm up. During summer months, put the tires in the sun before you change them so they’ll be more pliable.

Finally — take your time! If you’re brand new to changing motorcycle tires, it may take a few tries before you’re comfortable. 

Changing Your Tires

Start by taking the wheels off your bike. You must lift each motorcycle tire off of the ground. You could use a track stand, center stand, or anything else you prefer that will lift one end of the bike up.

Next, locate a flat space with plenty of room to work in. You could use a low table or bench. You may also want to lay down a piece of carpet to safeguard the finish of your wheels.

Take out the valve core before deflating the tube. You may see a nut on the outer layer of the valve stem, which is there to stop the stem from going into the wheel. Take off that nut.

If you own a dual-sport motorcycle, you may have a rim lock on the other side of the valve stem. If so, take off that nut as well.

Use a bead breaking tool to break the bead on the tire, but be careful to not hammer the rim too hard. After you break the bead, put in the rim protectors. Use spoons or tire irons to maneuver the bad to the outside of the rim. Take your time and don’t worry about moving too fast at this step.

Take the whole bead off on the one side of your rim, take out the tube, then turn over the wheel and break the opposite bead on the outside. That way, you can slip down the wheel inside the tire and pull it out on the other side.

After the wheel is barem check, the rim channel to make sure no debris remains. Also look at the rim strip to make sure there aren’t any spokes sticking through.

Assuming everything looks good, check out your new tire next. The tire shouldn’t have any debris on the inside and should have a smooth appearance. Use a tire past or light soap-and-water solution on the first tire bead, rather than WD-40 or oils.

Return to the wheel and install the first bead above the rim. If the tire is warm, you shouldn’t need a tool for this stem.

Now, inflate the new tube partially so you can get a little shape, Put the tub into the rim starting at the stem of the valve, then thread the locking nut on a few turns. Insert the tube in the wheel and try to keep it from folding so it won’t be pinched between the wheel and the bead.

After the tub settles, seat the other bead. Use your spoons or tire irons, progressing slowly until you reach the final few inches. Once you have the final part of the second bead seated, it’s time to inflate the tire.

Be sure that the beads are even around the tire rim on each side. Check for any loud hissing that could indicate you’ve pinched the tub. If you own a static balancer, now is a good time to balance your wheel. 

Closing Thoughts

Now that you’re a veritable expert on darksiding, it’s time to put your newfound knowledge to work! It ultimately comes down to your personal comfort level to decide if going to the dark side is the right option for you.

Do you tend to enjoy long-range cruising? In that case, it might be worth it to invest in new motorcycle tires to increase your motorcycle values rather than risking a car tire tread malfunction. If you only take your bike out for a spin now and then, tread might not be as significant a concern.

If you do plan on going to the dark side, don’t hit rubber to the road again before purchasing motorcycle insurance for your bike.