I’ve finally killed a Racerstar motor. It’s a BR2212 1400KV motor. I could have gotten a bit more life out of it. The grub screw that clamps the bell onto the shaft came loose after many hundreds of hours worth of flight on my AR Wing. The motor got hot and the wires melted. I supposed this is a rite of passage. Then again, I could have killed it off a lot sooner had I run 4S all the time and pushed the motor to its limits.
So, here’s my take on Racerstar motors.
The Good
Cheap as chips- The Racerstar motors are cheap. My BR2212 was $5. This is usually the point where people will say “I take the hobby seriously and I don’t have time for cheap motors.” Trust me, I hear you. But there is a difference between a plane that you rarely fly and one that is your go-to plane. How do you know how much you’ll like the plane? My thinking is that if you love the plane, sooner or later you’ll need to do some work on it. If it’s a PNP, replacing the plastic servos and cheap motor is nearly a given.
Far better quality than expected- I’d say it scores 75% on build quality. Essentially, if you have mild expectations a Racerstar motor will be more than enough to get you started. Had I been a bit more diligent in checking the set screw, I’d probably still be flying with the one I killed. But a lack of threadlocker on the grub screw in one of the many reasons why these motors don’t score higher.
The Bad
Thin wires- Thinner gauge means more resistance which ultimately means a cut in performance. Also the lack of bullet connectors is a turnoff
Price Point Driven- They are trying to throw a product into a box to make it as cheap as possible. I understand that it’s not ten times more expensive and appreciate it. But the cost savings between it and other motors isn’t huge.
What to keep in mind about motors
We owe a lot to our quad brethren. Next time you see them, thank them for throwing untold hundreds of millions of dollars at their hobby. They are people who like to throw full power at their quads for the duration of the flight. It’s with this extreme use that we benefit from motors that are usually more than up to our needs. When their motors stop, the fun ends. When our motors stop, the plane can often quietly glide back home. As the motors were made to withstand the abuse of quad pilots, our planes benefited. We have fantastic motors that are dirt cheap. And we usually only need one, sometimes two motors.
The Racerstar BR2212 rated a solid “C” for quality. You can get ¾ the quality for half the price of other motors, if not more. So, what are you paying for? The other 25%! How much that’s worth to you is really up to you.
Motor wires- The smaller the garden hose the less water can flow through it. Electricity is similar. Except, instead of water we talk about current. The narrow wires create more resistance. This is especially important when it comes to pushing the motor to the full extremes. One of the first things you’ll notice about the more expensive motors are the thicker wires.
Motor Windings- If you look at the difference between a Racerstar motor and a high end motor the windings look less crude on the premium motors. Perhaps the process isn’t as fast to make the nicer motors, which results in higher prices
Bearings- There is a strata of bearings. The better bearings are more expensive.
Other factors-
Construction of the bell, how the magnets attach, shaft materials used all are finer points. One other factor that is small is that Racerstar motors don’t come with bullet connectors. I have no problem soldering on my own. But I don’t thrive on the experience of doing this.
Where I see Racerstar motors fitting into the grand scheme of things
I don’t buy plastic gear servos anymore. What’s the point? They strip and die and I’ve actually had them die in flight which led me to go find the lost plane for about an hour. However, motors are another story. You can get by with a cheap motor for a while, long enough to understand if you like the plane, or if the plane needs a stronger motor, or a lighter motor to help with CG. There is nothing wrong with starting off with a Racerstar motor and seeing how the plane flies before making other motor decisions.
Keep in mind weight
One factor that isn’t discussed as much as it should be is the weight of a motor. If the weight is too heavy for your plane you’ll constantly be fighting CG issues. And if you can get it sorted out and can get the plane to fly it will need considerable speed to keep in flying and may very well land hot. This can lead to more damage to the plane over time and a shorter life of a plane.
Motor Specs-Anything but scientific
The motor specs listed on websites when you’re looking to buy a motor are at best suspect. There are no standards to which the motors are measured. If they were truly scientific they should be repeatable. At best, they are directional.
Then you have some very well intentioned individuals who hook up batteries and speed controllers to scales to give a bit more real world test with batteries and props they list. The issue is that the batteries sag under use and the rate of sag varies by battery. In order to do this properly you would need a more consistent power supply that wouldn’t sag underload. Again, this is directional and often very revealing about the true specs of a motor. Sometimes the thrust is greater than what is published.
In the real world example they often show propellers of similar size but from different manufactures. The results can vary, sometimes there are large variances. Propellers are often like motors, the more expensive ones provide a bit more thrust.
Efficiency
Grams of thrust/watts=efficiency.
This is a common way to rate motors. It can also be misleading in the respect that some motors are built for getting the last bit of thrust out of the motor. They get hot and start consuming amps. You pay a steep price in efficiency to get that last bit of thrust. But, this is the market they are after. They are built for people who want to get the ultimate performance out of the motor. Many of the newer quad motors can run exceedingly high temperatures. Sometimes they list the temp readings in the motors specs
Meanwhile, there are some motors that have low amp draws that are very efficient when it comes to the specs. It’s because they never struggle. If you look at the specs you’d think that it’s a more efficient motor. When you start comparing how much power it takes to get 200 grams of thrust, or 500g or whatever level you’re cruising at you may find that the motor built for speed will hit these levels with less power than the so called “efficient” motors.
Putting it all together
People approach building planes from very different angles. I was at one point in love with getting a new plane every few weeks. Thus, I ended up with a lot of planes. I couldn’t afford to put the top of the line everything into so many different planes. But, when I started to rebuild them, the ones I liked I wouldn’t see an issue with upgrading a motor, and putting on better props.
I am not a motor snob. I am a cheapskate. Thus, for most planes that I rarely fly, the Racerstar motor is more than fine. But, if it’s a plane I like to take up quite often, I’ll spend the extra money on Sunnysky or another brand.
Racerstar is like McDonalds. It’s not going to be the best meal of your life, but you’ll know exactly what you’ll get.
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