This instructable is intended to help you learn how to rebuild a front wheel hub on any bicycle. Any avid cyclist should know how to rebuild a wheel hub. Rebuilding the hub on your own also saves the time and money that many people spend at bike stores, when they can do the maintenance themselves. Rebuilding a wheel is a very simple procedure, and it can be done with very simple tools. If you can turn a wrench, you can rebuild a bike wheel hub. Plus, it takes no more than 30 minutes.
All modern bicycle wheel hubs are the same. One can use the same tools on a mountain bike wheel hub just as he/she can on a road bike wheel hub. In this demonstration, I will show you how to rebuild the front wheel hub on a road bike. There are many ways to rebuild a wheel hub. I discovered this method on my own, using simple, nonspecialized tools.
Step 1: Understand Component of a Front Wheel Hub
It is important to understand the components of the bicycle before attempting to take it apart.
Axle : Runs through hub and rotates
Bearings : Orbits around the axle on both sides of the hub
Cone : Secures the bearings in place
Hub shell : Encloses the axle
Locknut : Secures the cone nut in place
Step 2: Assemble Tools Required
As mentioned before, the tools needed to rebuild a wheel hub are simple, everyday tools. The tools you need to rebuild a front wheel hub are:
13 mm wrench:
The 13 mm wrench is for the cone nuts.
13 mm is the the universal diameter for all front wheel cone nuts
Comment: Some people recommend the use of cone wrenches. The only difference between a cone wrench and regular 13 mm wrench is that the cone wrench is thinner. This allows the biker to adjust the tightness of the cones without having to disassembling the hub. Cone wrenches cost around $10. Personally, I believe they are unnecessary.
The adjustable wrench is for the locknuts, which sometimes vary in size.
Locknuts typically range from 14 mm to 17 mm
Over time, the bike wheel will accumulate dirt. Combined with bike grease, it creates very thick grease that clogs up the hub. This grease will stain clothes and cause a lot of mess.
There are many ways to remove grease. My personal favorite is a combination of aluminum foil and vinegar. It removes not only grease, but also rust.
When the unwanted grease is removed, new grease is needed to lubricate the wheel hub
Any grease from a department store will suffice
Dirty rag/Paper Towels
Working with a bicycle is often messy, especially with grease. This is why it's best to have an abundant supply of paper towels or a dirty rag to help collect the grease.
Bike grease is difficult to clean off. Some people prefer to keep their hands clean.
Step 3: Disassemble the Wheel
Disassembling the wheel is a fairly simple process. Simply start with the outer nuts and work your way in toward the bearings.
Tip : Be careful when unscrewing the cone nuts, because beneath these are the ball bearings. If not carefully handled, the ball bearings may drop out of the hub and scatter everywhere. You don't want to loose these bearings. Instead, carefully unscrew the cone nut and let the bearings drop into your hand.
Tip: Align the various nuts in the order they were disassembled. This helps you keep track of where the parts belong when you put it back together.
Step 4: Clean the Parts of the Hub
For this particular step, I like to use aluminum dipped in vinegar as degreaser. Other people like to use dish detergents. Either way, they both get the job done.
Step 1: Dip a small piece of aluminum foil into vinegar
Step 2: Rub the aluminum foil against any metal surface to remove the grease
Comment: Rubbing aluminum foil against rusted parts of metal will also remove the rust. This is also important because rusted metal causes friction in moving parts.
Step 3: Dry the metal surface with paper towel.
Comments: Paper towels are easily disposable, whereas rags accumulate grease.
Step 4: Repeat this cleaning procedure to all the parts of the bicycle.
Tip: It may be difficult to clean the inside of the hub shell using aluminum foil. What I like to do is to roll a paper towel into a long, thin strip, and run that through the hub.
Step 5: Lubricate All the Moving Parts
One of the most important concept in bicycle maintenance is to lubricate the moving parts of a bicycle. In this case, grease is used instead of regular, liquid lubricants. This is because liquid will seep out of the hub over time. However, grease is a solid gel, allowing it to remain inside the hub for a long time.
Step 1: Extract a small amount of grease with your finger. The pictures provide a good illustration on the right amount of grease to use.
Tip: Too little grease will cause friction in the bicycle hub, thereby speeding up erosion of the bearings. Too much grease will attract dirt, thereby forming that nasty, unwanted grease.
Step 2: Scrub grease around the outer end of the hub shell. (seen in first picture)
Tip : Try to keep the greased parts away from dirt. These sediments will speed up erosion of the bearings inside the hub.
Step 3: Scrub grease around the smooth section of the axle. This is the part that makes contact with the inside of the hub shell, so it's important to put a good amount of grease here.
Step 4: Scrub grease around the slanted edge of the cone nuts. This the part of the cone nut that makes constant contact with the ball bearings, so it's important to keep this part well lubricated.
Step 6: Install the Bearings
Some people find it necessary to use special tweezers to place each individual ball into its place; but this is not necessary. You can successfully put in the bearings without using any tools at all.
Step 1: Screw one cone nut onto the end of the axle
Step 2: Run the axle through one end of the hub. Make sure that the bare end of the axle is pointing up.
Step 3: Carefully drop the bearings into place. (see first picture)
Comment: The axle is blocking the hole so that the bearings won't fall through the hole.
Step 4: Screw the other cone nut to the bare end of the axle. Make sure to screw all the way down.
Step 5: Flip the wheel over such that the side of the hub that is still without bearings is facing up.
Step 6 : Unscrew the cone nut on top such that there is enough space for bearings to go through. (see second picture)
Step 7 : Drop in the Bearings.
Step 8 : Screw the cone nut in such that it closes the hub, securing the bearings in place.
Step 7: Close the Hub
Step 1: Ensure the axle is evenly spaced on both sides. Adjustment can be made by slightly unscrewing the cone nut on one side and screwing in the cone nut on the other side.
Tip: Make sure the cone nuts are not too loose or too tight. If the cone nuts are too loose, the wheel will shift from side to side when it turns. If the cone nuts are too tight, it will cause friction and resistance when the wheel turns.
Step 2: Screw in the lock nuts.
Tip: The locknuts should not be too tight. All they need to do is to make sure the cone nuts don't slide. Screwing them on too tight will push the cone nuts in toward the bearings.
Step 3 : Install the axle nuts, or whatever other parts that came with the bicycle. These parts vary due to the different release mechanisms built on bicycles.
You are all done! This concludes my instructable on how to rebuild a bicycle front wheel hub using simple tools. You are now ready to rebuild your own bicycle wheel hub.