Changing a Scooter Wheel Bearing

Stop and Get Your (Scooter) Bearings
One category of scooter parts that almost flies off of the Monster Scooter Parts warehouse shelves is the humble scooter bearing in all of its size variations. Just about anything with "scooter" in its name will roll on bearings, and almost anything that rolls on those bearings will need new ones sooner or later. We have scooter wheel bearings for everything from kids' kick scooters and bearings for recreational scooters to bearings for motor scooters. Somewhere in the middle are our bearings for mobility scooters and power chairs. Most of these are (other than size) functionally identical, and the same size scooter wheel bearing might be found on the front wheel of a little stand-up electric scooter, or the caster assembly of a heavy duty 6-wheel electric power wheelchair.

Changing a scooter bearing does not have to be an intimidating experience, and anyone with a rubber mallet, two old wrench sockets, and a few minutes time can do it.

Removing & Installing Scooter Wheel Bearings
A well-made, correctly assembled, wheel hub and wheel bearing assembly on anything larger than a skateboard should be a little more than just a snug fit. The perfect fit would be tight enough to keep from coming apart at inopportune times, yet not so jammed together that it takes a chisel or sledge hammer to separate the two parts.

Lubrication
Often a little common household penetrating oil applied to the seam between the hub and the bearing case will (if allowed to sit for a bit) make life a lot easier for anyone trying to force a worn old bearing from its accustomed home. When inserting a new scooter bearing, a little white lithium grease on the outer case will help slide a new scooter wheel bearing into place. The emphasis here is on little; almost any more than a thin film is superfluous and will be scraped off by the tight fit.

The Laws of Physics
Heat expands matter and cold contracts. We all learned this in Junior High School science class. So if you stick your bearings in the freezer for an hour or so, they will shrink just a tiny bit. If practical, you can warm up the wheel hub in hot water for a while. If the law of physics take its course, your scooter bearing will be a tad smaller in circumference, and your wheel hub just a smidgen larger than they were at room temperature. Don't expect a drop-in fit. The idea is to make it a little easier to persuade your scooter wheel bearings to move in or out.

One caveat here; do not be tempted to break out the propane torch! The intense heat of the flame will probably damage any plastic or rubber on the wheel or caster assembly. In addition, sudden intense heat will stress and weaken the metal. If you absolutely must heat the hub in record time, use an electric blow dryer, but don't tell anyone that I told you.

Brute Force
Nothing short of brute force is going to move a rusted, damaged, or deformed bearing; and a wheel bearing that is only finger-tight won't stay in place doing its job for long. Either way you are going to need a bit of mechanical force to persuade any proper fitting scooter wheel bearings in or out of a wheel hub.

The proper tool for the job is an arbor press, a device found in almost every well-equipped mechanic's machine shop. But if you are not a professional mechanic or own a well-equipped machine shop you will need the old tried & true rubber mallet method.

The Civilized Method
So you have your cold or oil-soaked scooter bearing and a hot hub. How do you move one through or into the other? Brute force again by way of a rubber or wooden mallet, but applied scientifically. Here is where the old wrench sockets come handy. You will need one socket a bit larger than the diameter of the bearing, and another socket that is slightly smaller. If your bearing is an externally nominal 22mm, you will want a 3/4" and a 1" or larger socket. Whatever the size; one just under and one over the bearing's external measurement.

A. You will need a steady flat place for this. A big wood plank or block on your garage floor is perfect for this operation. Place the larger socket upright on the block and center the wheel hub balanced on the socket.

B. Put the smaller socket on the bearing.

C. Smack small socket with mallet.

D. Wash, rinse, and repeat as necessary.

This method is basically the same whether you are removing an old bearing or inserting a new one. The large socket supports the hub without getting in the way of the bearing. The small socket pushes the bearing in or out.

And one more caveat here; you might accomplish this by chocking the hub into a vise and then going at it with a hammer and big brass drift punch. Chances are you will end up damaging either the hub, the bearing, your knuckles, or possibly two out of three or all the above. In that case, you will need a new set of scooter wheel bearings and a whole new hub. Don't worry, Monster Scooter Parts has them.

www.monsterscooterparts.com/