Sun is shining, bike’s loaded up, and your engine is rumbling waiting for you to take off on your journey…but wait. Did you check to make sure your tires can carry the load you’re carrying on them? It’s easy to exceed your load capacity and something few people actually check, so we’ll tell you how it happens and how to prevent it here!
Your bike is clean and polished up, the sun is shining, your gear is all strapped up, and your motorcycle’s engine is thumping away, filling the air with the sweet sound of an idling engine just waiting for you and your passenger to hop aboard and twist the throttle on your upcoming journey. But wait a minute, one more important thing…did you remember to check your tires load capacity?
We know, it’s not fun and it’s not sexy…but it may very well be the most important maintenance step you take before stepping off on a long trip on your bike, especially when you’re carrying extra gear, a passenger, or both. On a motorcycle, a vehicle that carries hundreds of pounds of weight on two tiny patches of rubber that add up to the size of a credit card, tires take on a whole new level of importance – and making sure they can handle the load you’re putting on them is crucial!
So in this article, we’ll tell you about what load capacity is, how to use a tire load rating chart to determine if you’re exceeding it, and a few helpful tips to make sure your tires are up to the task of carrying you where you need to go with total peace of mind!
What Is Load Capacity Anyway?
Simply put, the load capacity of your bike is the maximum weight that your bike is rated to carry safely. Under normal use – say, riding around town solo with no luggage, for example – your bike can probably carry a lot more weight than you are putting on it, so no need to worry. But start adding weight to your bike by taking a passenger, strapping up some gear, or both, and you can come dangerously close to or even exceed your bike’s load capacity without even realizing it – and creating a dangerous situation as a result.
Overloading your tires can cause sluggish handling, heavy steering, and an uncomfortably overworked suspension – and that’s in a best case scenario. Worst case, your tires can become damaged internally and fail, or even become dislodged from the rim, causing a catastrophic failure…and that failure may not even happen when the tires are physically overloaded, but at some later date when the damage caused during previous overloading finally catches up to you. Trust us – it’s just not a problem you want to have!
Sounds Scary…So How Do I Know If My Tires Are Overloaded?
First of all, we’re going to confuse you by telling you that there is not one load capacity you need to be aware of, but two – one for your bike itself, and one for the tires you’re installing on it. Both need to be up to the task of carrying the loads you pile onto them, because failures can arise in either your tires, or in the bike itself (usually in the suspension components) if they aren’t.
To make sure your bike and tires can handle what you’re asking of them, there are two steps you need to take: first, determining what the load rating of both your bike and your tires is, and second, determining how much weight you’re actually hauling around.
To determine your bike’s load capacity, you must refer to your owner’s manual. This will tell you how much weight you can pile onto your bike in its stock form, including the stock tires – this is known as your Gross Vehicle Weight Rating, or GVWR. To determine the load capacity of your tires, however, you will need to check the tire itself for the load rating code, which is found stamped on the sidewall of the tire (usually after the tire size markings.) You will find a two-digit “load index” code, between the numbers of 33 and 90, that will indicate the total weight those tires can handle under proper use.
This chart shows load rating codes and what load capacity they indicate, which can be found on the tire after the size and usually accompanied by the speed rating. This chart is courtesy of our friends at the Motorcycle Safety Foundation.
That last part about “proper use” is key – underinflated tires (which are more common) will handle and corner sluggishly, reduce tire life and mileage, and accelerate wear, while overinflated tires will cause a harsh ride and increase the likelihood of a puncture or breaking due to sudden impact on the road. Either way, a tire will not perform optimally if it is inflated to outside its recommended pressure, or being driven past it’s factory speed rating, so you need to be mindful of both.
The Numbers Don’t Lie
Knowing your ratings is only half the battle – you also need to know how much you’re actually piling onto your bike and those tires of yours to make sure you’re not exceeding them. Luckily, there is a simple formula you can use for exactly that. Check it out below:
A handy form to determine your load capacity and whether or not you are exceeding it, courtesy of Dunlop.
Here’s how it works. First, you need to determine how much load capacity you actually have to work with. We mentioned finding your load capacity, or GVWR, in your owner’s manual (you can also find it stamped on your VIN plate, which is usually mounted onto the frame.)
GVWR consists of every pound your bike can possibly weigh safely, including it’s own weight. So to determine it’s carrying capacity, you need to take the GVWR figure and subtract the dry weight of the motorcycle as shipped from the factory (also in the owner’s manual), plus the weight of all fluids, fuel, and oil (which weighs about 40 pounds on average.) The resulting figure is your available load capacity.
Now you need to figure out what you’re actually carrying. This consists of your weight and the weight of your passenger (if applicable) with all your gear on, plus the weight of all cargo and luggage you’ll be carrying, plus the weight of any accessories you’ve added onto your bike, such as hard bags, a windshield, custom parts, etc. (you forgot about that last part, didn’t you?) This figure is your total load.
The last part is simple: if your total load is greater than your available load capacity, you’re overloaded. That means you are at risk of not only poor control and handling, but actual tire failure that can be catastrophic. And remember, you have to make sure you’re not just exceeding the weight rating of your bike, but the tires too – and if you’ve installed anything other than OEM tires on your bike, your load rating may not be the same as it was from the factory, so you must check both to be safe.
In the motorcycle world, it is not uncommon to have 600, 700, even well over 1000 pounds being carried completely by two tiny patches of rubber, over hundreds or even thousands of miles of roads, on and off road, packed with every kind of hazard you can think of…so it really is critical to make sure you’re not piling more onto your tires than they can handle!
Still have questions about the load rating of your bike or tires? Feel free to contact us by phone or email, and we will help you out!