You know that racing motocross is an expensive hobby. It seems like your bike is always in the shop undergoing regular maintenance, changing the air filter, or replacing the brake pads. Now, you have a broken or leaky fork seal, an empty wallet, and no desire to get back to the shop.
You should notride with a bad fork seal for many reasons, safety being number one. A bad fork seal could leak oil onto your brake calipers, resulting in trouble decelerating and stopping the bike. That, plus poor shock absorption and an unbalanced ride makes a leaky fork seal dangerous to ride on.
It looks like your bike needs a couple of repairs. So, keep reading to learn about what the fork seal really does, why it may become damaged, and why a damaged seal may be dangerous. Then, we’ll talk about some potential solutions to fix a bad fork seal.
The Purpose of the Fork Seal
To understand why a functioning fork seal is so important, you need to learn about what a fork seal is supposed to do.
The “forks” of your bike are those two large tubes that are attached to your bike’s front wheel. They are designed to help you to actually steer your bike, control your front brakes to slow down, and absorb shock from bumps and jumps during your ride.
Inside of these tubes are springs and oil.
The oilinside this fork tube is meant to dampen the speed of the fork compression and rebound so that they’re always performing at maximum capacity. That keeps your bike’s ability to absorb shock as consistent as possible.
Then, there's the actual fork seal.
This is a small circular ring that attaches to the bottom of the fork tube to keep the oil inside of the tube while you’re riding. Without this fork seal properly secured, your fork will leak that oil down the fork tube, and potentially onto your brake rotor and brake pads.
Causes of Fork Seal Damage
A bad fork seal can be a nightmare for both novice and advanced riders. Now, you’re probably wondering what actually causes this sort of damage? Here’s a look at a few common culprits when it comes to a bad fork seal.
Physical Damage: One of the least common causes of a bad fork seal is physical damage to the seal. This might be caused by getting into an accident on your bike, sharp rocks that get caught in the seal and scratch/tear it, or a nick in the fork tube that rips the seal.
Dirt or Debris Buildup: In most cases, a bad fork seal isn’t really bad. There’s simply dirt that’s trapped alongside the fork seal that’s keeping that gap from fully closing. This can cause oil leakage and ruined suspension.
Age: If you’re lucky, your damaged or bad fork seal will come from years of consistent use. Many fork seals will last between 20 and 80 hours before finally falling apart and needing to be replaced.
The good news is that a bad fork seal isn’t the end-all-be-all for your bike. In most instances, you’ll just need to make a trip down to the repair shop to get them fixed.
Just keep in mind that this is the type of repair that you’ll want to make sooner rather than later.
The Dangers of Riding With a Bad Fork Seal
Your bike’s fork seals are probably some of the smallest pieces that go into making your bike function. Yet, they also can wreak the most havoc when it comes to safety, time, and your wallet. So, let’s go over why it’snot a good idea to ride with a bad fork seal.
The longer your fork seals leak, the more oil that drips onto your front wheel below. The fork oil will also begin leaking onto your front brake pads and calipers.
As you might be able to figure out, this can be extremely dangerous.
When your brakes become too lubricated, their ability to stop your front wheel when you clamp down on your brakes is practically non-existent. You’ll have trouble decelerating and stopping.
Instead of being able to slow down before a curve or a turn, you’ll approach it at full speed. You know after years on the bike that you’ll probably be thrown off or hit another obstacle if you take a turn too quickly.
Not being able to stop in a congested area of the trail can lead you head-on into a tree or other rider.
In some cases, only one of your front fork seals will go bad. So instead of oil leaking from both sides at a consistent pace, you’ll be primarily losing this oil from the left fork or from the right fork.
That might sound like a good thing at first because it means fewer repairs.
However, the problem is that shock absorption will be much greater on one side of your bike than on the other. So, you won’t be able to prepare for how your bike will handle potholes, bumps, or rocks on the trail.
This poor balance in your front wheel will also make handling and steering more difficult than usual. Don’t be surprised if you’re thrown off your bikeon a usually simple trail. This should be a good indicator that something needs to be fixed.
Less Shock Absorption
Perhaps the most dangerous aspect of a bad fork seal is poor shock absorption. Right now, you know which holes and bumps your bike can take without damaging your bike or throwing you off in the process.
With low or no oil in one of your fork tubes, the spring on just one side may absorb next to nothing. On the other hand, your bike might absorb too much.
The result can be an extremely bouncy ride, feeling every single bump on the trail, and even injuring yourself when coming down from a jump. Your bike needs shock absorption to recover from bumps and jump landings to prevent damage.
How to Fix a Bad Fork Seal
In most cases, your fork seal will leak oil as a result of dirt build-up.
To figure out if that’s the issue you’re facing, examine your fork seal for any signs of noticeable damage. There shouldn’t be any dents, scratches, or holes in your fork seal.
The Seal Doctor will be your best friend if the problem is actually just dirt caught in the seal.
Here’s a step-by-step guide for how to use the Seal Doctor.
Lower the dust seal from the tube (Note: Some oil might leak out, but that’s to be expected at this point in the process).
Simply snap the Seal Doctor around the tube.
Slide the Seal Doctor up so that the pointed area is underneath the tube where your dust seal normally sits.
Spin the Seal Doctor around the tube to scrape away any lingering dirt.
Detach the Seal Doctor, wipe away any excess oil, and plugup the dust seal.
This is the easiest fix and saves you from having to buy a brand new fork seal and take apart your entire bike. Check out this video that shows you exactly how this product works!
Riding with a bad fork seal is not only extremely dangerous to you, but to other riders as well. You may also have to replace parts that have become damaged due to the leaking or lack of oil.
Luckily, fixing a bad fork seal isn’t too hard if the problem is just a dirt build-up. For less than $25, you can invest in a Seal Doctor and return your fork seals to working condition.
If there’s noticeable damage to your fork seal that can’t be fixed via Seal Doctor, it’s best to spend a little money and have this fixed at the shop.