One of the amazing things about motorcycles is that a lot of the mechanics and components on them can usually be fixed by the owner with a little help from the internet, a friend, or the owner’s manual.
You may have been riding down the road and hit a big pot hole in the road, ran over a large branch, or did something similar. The outcome for instances like these are often bent rims. When I first started riding a motorcycle, I often wondered if this is a fix that can be done myself.
So, can a bent motorcycle rim be fixed? If it is causing vibrations and a wobble, a bent motorcycle rim can be fixed but it should be done by a professional or it needs to be replaced. It is not advised that you fix a bent rim yourself as there are too many risks involved. The metal on a bent rim cannot be reformed perfectly to it’s previous shape without the right heavy machinery.
Out of the several motorcycles I’ve owned, I’ve had my fair share of bent rims on them. I attempted to fix them myself only to find myself in a bigger mess than I was in before. There is a lot to consider when fixing a bent rim and it’s important knowing the options you have.
How A Bent Rim Is Fixed
As a disclaimer, a lot of rims will have very small and slight bends in outer lips. If this is your case and these bends don’t cause any riding issues, you probably don’t need to worry too much about them. If you want to though, you should be able to fix them yourself with the right set of tools. If there are bends in your rim that are very noticeable or you have bends that cause the wheel to wobble or the motorcycle to vibrate, this article applies.
Having a bent wheel on a motorcycle is incredibly frustrating. Not only is it dangerous to ride on, but it’s usually pretty uncomfortable because of the vibrations or bumpy ride it causes.
It can be incredibly tempting to fix it yourself, but it’s important to remember that noticeable rim bends is a fix that needs to be left for the professionals. Professionals have a certain way of fixing them and I’ll explain how they do it.
The reason I’m explaining how the professionals fix a bent motorcycle rim is to emphasize the large and specialized equipment needed to perform such a fix that most amateurs don’t have at home. I’ve seen different shops use slightly different types of tools, but the basic process is the same.
The mechanic mounts the rim on a machine that allows the rim to spin in front of them. There is a sensor they use that usually consists of a needle like point that’s placed right behind the inside of the outer lip of the rim. This sensor is able to give specific numbers and indicate the severity of the bend.
Once they locate the bend, they use a torch to heat up that spot up between 300° – 400° Fahrenheit which makes the metal easier to work with. Then they place a half moon shaped device inside the rim (specific to the rim size) where the bend is and the machine applies pressure to that spot. Once that spot cools down a little, they run the needle sensor over that spot to ensure the bend is gone and the surface is within a normal, safe range to drive on.
Sometimes bends in wheels can cause cracks. If this is the case, the mechanic has to cut out the metal around the crack, reweld it, reshape it to what the rest of the rim lip looks like, then straighten the whole thing out.
Like I said, each shop is a little different with how they straighten wheels, but they all have sensors on their machines as well as that specific dial that reads the smoothness of the inside of the rim. This is very important equipment to have when straightening a motorcycle rim and I doubt most motorcycle riders have equipment like that.
If you find yourself with a bent motorcycle wheel, it’s a good idea to call around to a few shops and get some quotes. Along with that, shop around for prices of a new rim. A lot of times it may simply be cheaper to just get a new rim.
Rim repair shops will cost anywhere between $65 – $400 depending on the severity of the bend. The average price I’ve seen for a new motorcycle rim is about $200, but you can find one cheaper if you buy one that’s used.
Why You Shouldn’t Fix A Rim Yourself
If you ask around a little, you’ll hear of a lot of people who suggest to simply fix the rim yourself. Some people may have been able to get away with such a fix, but the risks of doing so are too high. As an engineer, it makes me cringe to think people are fixing their own rims and riding on them.
Doing a fix like this on your own may seem easy, but there’s actually a lot more going on with the metal than you realize. Even if you think you’ve fixed it and it looks brand new, it probably isn’t.
Without the proper sensors and equipment, a bent wheel is extremely hard to shape back to the form it was previously in. In addition, rim bends can also have underlying cracks and breaks in the metal you can’t see that a mechanic would be able to catch.
When attempting to fix a rim themselves, people often cause more damage to the rim rather than actually fixing it. Hammers are often used to “pound out” the bend, but that’s just furthering the problem and not fixing it at all. Crow bars are also often used and though they may seem to fix it, those also cause other small bends and dents that could be dangerous to the function of the motorcycle.
You have to think of this logically; if you’re planning on fixing a bent wheel yourself, you’ll have to take it in to a shop to dismount the tire then take the wheel back in to remount the tire (because you can’t have the tire on while you’re fixing it). The cost to dismount a tire is about $20-$40 and about the same to remount. So by this time you have already spent $40-$80 on your “DIY” fix.
That’s already a large chunk of what it would cost to just take your rim in to get it professionally straightened (dismounting and remounting the tire is included with their rim fixing prices) or it’s almost half the price of simply getting a new rim.
The Dangers Of Riding With A Bent Rim
I’ll often hear the argument that people fix their car rims all the time and it turns out fine, why is a motorcycle rim any different? I’ll admit, I have fixed a bent rim when I was restoring a ’68 Firebird and it was something I shouldn’t have done. But remember, cars are very different from motorcycles, especially when it comes to wheels. One wheel on a car is 25% of the balance while a wheel on a motorcycle is 50% of it’s balance.
When a bent rim isn’t properly fixed, you run the risk of your tire deflating or creating bulges while you’re out for a ride. It’s also possible for the tire to blow during the ride because of the improper suction it has against the rim. This especially applies to tubeless tires.
A tire blowing or suddenly becoming flat is extremely dangerous while on a motorcycle. That has the potential to throw you off the bike and result in severe injuries.
If you have a bent motorcycle wheel that causes wobbles on your ride, you may have a rim that’s considered “out of round.” Rather than having a deep bend or flat spot on the lip of the rim, the rim itself is crooked by looking at the back profile of it. Each time the wheel goes around during a ride in a condition like this, the bend becomes worse with the constant pressure and will eventually “taco” or completely bend in half.
How A Rim Gets Bent
There are several types of common bends that a motorcycle rim can have and there are various ways that those bends are created. Some bends are much less severe while other bends are completely dangerous to ride with.
Bends usually happen when the motorcycle comes in contact with something on the road at fast speeds. Common rim bend reasons are from large pot holes in the road, unexpected speed bumps, or some sort of accident and impact with another vehicle.
Sometimes, however, bends in motorcycle wheels happen and we have no idea how they got there. It is possible for a slight bends to happen months earlier and with constant riding and other slight bumps in the road, the bend gets accentuated to a point where it becomes noticeable.
A bent rim will often give the symptoms of vibrations and a wobble. A bent front rim usually causes a wobble and shakiness in the steering column while a bent back rim usually causes vibrations.
Why do motorcycles have different size wheels? Most motorcycles have larger front wheels to help with movement and steering. The back wheels are shorter in diameter and wider to help with traction and control of the motorcycle since that is where the power is coming from. Click here to see an article I wrote that explains this further.
What are the signs of a cracked rim? Aside from the signs of a bent rim, a cracked rim may also manifest itself with noticeable thumping sounds, a pull to one side, and a noticeable extra usage of gas as it will cause a lag with the vehicle.