RC Car Ball Bearings Vs. Bushings

The RC Car and Radio Control Racing Web Site

WHY BEARINGS ARE GOOD

Let's talk about ball bearings for a bit. They are probably the single best upgrade that can be made to an RC car. Why? There are many reasons such as a smoother running car, less drag, tighter tolerances, and they last longer than plain bushings.

Ball bearings look simple but there is much to them. There is an inner race which fits tightly on the shaft it is used for, there is an outer race which fits tightly in the hub or bulk head it is used for, and there are balls which roll between the inner and outer races. This rolling effect is what makes a ball bearing superior to a plain bushing. The tight fit between the shaft, bearing, and bulkhead it what greatly reduces the tolerances of moving parts.

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Most RC cars don't come with ball bearings. Instead they come with a plain bushing. A plain bushing is made of a softer material than the shaft it runs on and rubs the shaft constantly as opposed to rolling on smooth balls as a ball bearing does. This rubbing effect has two detrimental outcomes. First, there is more drag or resistance in the shaft which reduces the power and speed of your vehicle. Second, the increased drag and resistance causes a build up of heat and increased wear. The increase in wear is a major problem with bushings that most people over look.

Let's say that you run your car for a year with plain bushings before you change to ball bearings. No big deal right? Yes it is. As mentioned above, a bushing causes more wear to your vehicles moving parts. This means that the hole in the bushing will wear a little bigger and the size of the shaft will wear a little smaller. This creates a "sloppy" loose feel in the car. A "sloppy" car does not react as well to our driver inputs thus making the car slower and harder to control. So who cares? "When I put ball bearings in my car all of my problems will be solved." Wrong! The reason a ball bearings works so well at reducing the tolerances in your RC car is because it fits tightly on the shaft and in the hub. If you have worn the shaft down with the use of a bushing, the bearing will no longer be tight and a lot of the advantage of ball bearings will be lost. This is one of the main reasons why, if you have to use bushings, it is better to use plastic ones as opposed to metal ones.

Many companies are content to brag about their inclusion of metal bushings with a kit. They say that they last longer and don't wear out. They are perfectly correct. You will not have to replace a $5 set of bushings very often. You will however, have to replace about $60 worth of shafts when it comes time to replace your plain bushings with ball bearings. Plastic bushings are very soft and they do wear out quickly but they do minimal damage to your vehicles drive shafts. This way when you decide to upgrade to ball bearings your shafts will be almost new and the full benefit of the ball bearings can be appreciated. I would much rather replace a cheap set of plastic bushings than all of the expensive shafts in my car. Don't think you can solve all of your problems by greasing up your bushings and shafts either. Go to "Wear to Use Grease on an RC Car" to find out why.

The entire point of this article is to explain to people that there are many advantages to ball bearings than are not commonly known. It is an excellent upgrade to any car and it is very important that you do not wait too long to make this upgrade or the full benefit will not be received. I did not write this to scare everyone into running to their closest hobby shop and buy a set of ball bearings, I just want to point out a topic that most people don't realize about the most popular modification in our hobby. Before you soak a ton of cash into your vehicle to buy a carbon fiber coated, titanium nitrite, hard anodized two speed tranny, think about installing a good set of bearings. They will increase the performance of your car much more than most other RC upgrades will.

Let's take off a few tenths per lap,

"PRO"