Here is a step by step guide on how to change a go kart wheel bearing (or bearings). On most American made yard karts, you will have 5/8″ bearings in the front, and 1″ bearings in the rear. The 5/8″ I.D. (inner diameter) 1 3/8″ O.D. (outer diameter) front bearings should have a spacer in between them and come in pairs for a hub or rim. Live axle bearings typically have a 1″ I.D. with a rounded exterior that is held in place by axle hangers in conjunction with bearing flangettes.
How to remove go kart wheel bearings.
First, remove the spindle nut, and the hub assembly or rim assembly should just slide right off. Place the rim or hub assembly on a hard surface (concrete is good, or a vise). Next, use a pipe or round bar that has the same outer diameter as the bearing’s inner diameter (5/8″). Push the rod through the first bearing, then angle it to catch the inner race of the bearing furthest away, then hit the rod with a hammer to push out the bottom of the bearing. Flip the rim or hub assembly over, and repeat to remove the other bearing
How to install new bearings
It is easy to change go kart bearings once you have the old ones out, but if you are not careful, you could damage the new ones. Most bearings come greased and sealed, the key is not to damage the seal or break the bearing as you install it. If you need some new high speed go kart bearings, you can buy them here.
If you are replacing the bearings, the rim or hub assembly may have rust, old grease, and debris that will make it harder to install a new bearing. You can use some sandpaper or a wire brush to remove most of it.
When installing a new bearing, use a pipe or socket that will fit against the outer race of the bearing, and tap it in with a hammer. Make sure to put the spacer back in between the two front wheel bearings.
Re-Installation of Go Kart Rim or Hub Assembly
Once you have your bearings in, simply slide the hub assembly or rim back onto the spindle, and tighten the nut back onto the spindle but not all the way. Do not over torque the spindle nut, doing so will damage your new bearings, or cause excessive amounts of friction which will cause the bearings to fail very quickly. It’s a good idea to put some thread locker on the nut, then very carefully torque the nut so it is touching the bearing. A good way to tell if you have done it right is to try and push the wheel back on forth on the spindle, if it does not move, that is what you are looking for. The spindle nut does not need to be tight. Another way to make sure you haven’t overtightened the nut, is to lift the wheel off the ground, give it a spin, and then slowly tighten the nut. If the wheel stops, or slows quickly, the nut is too tight.
Go Kart Rear Axle Bearing Removal
Rear axle bearing replacement is relatively simple. Some bearings have set screws on them, which need to be unscrewed. You can buy new rear axle bearings here. If the kart is old, the axle may have rust on it. Spray PB Blaster (a rust penetrant spray) on it and wait at least 10 minutes. You can usually knock the bearing free with a hammer. If the bearing is stubborn, you can use a pipe with an ID of 1″ to fit over top the axle, and rest it against the bearing’s inner race. Hit the pipe with a hammer and the bearing will slide off.
Rear Axle Bearing Installation
Changing go kart axle bearings is simple. Slide the bearing onto the axle, and do not tighten the set screw(s). First, tighten the axle hangers or flangettes over the bearing’s outer race, then make sure your axle is centered by measuring the distance from the bearing to the end of the axle on each side of the kart. After you are sure you have it just right, tighten the set screws. For added strength, you could unscrew the set screws, and drill a shallow hole (<1/8″) where the set screw marks are. I do not do this, instead, I place spacers between the rim or hub and the bearing on each side of the kart, making sure they do not add any pressure on the bearing as it may cause premature wear and failure.
More go kart maintenance questions? Visit the maintenance section here.
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