Edit: I have flow these today 12.11.2017, they are smooth and quiet, I have flown 7 packs and it they aren’t even getting warm after 3 minute flight in typical racing conditions with DAL 5046C props. They really open up and show full potential above 60-65% throttle. It seems that these motors have a lot of power and accelerate really fast.
Here is a test video with the first pack
Edit 2: I have been flying these with Dal Cyclone 5046 and I really like the torque they provide on low throttle, they seem to be more than able to work with heavier props. I have found this youtube review with thrust results https://www.youtube.com/watch?v=l3fxH… and they seem to pull 1400 grams and drawing around 40 amps on 5046C at max throttle.
You are getting what you have paid for. These motors are certainly a bargain for a cheaper builds and also as motors used for training without worrying if you destroy them. I have ordered these as soon as they were available for sale on BangGood. I was worried a bit since there were no reviews, but based on my previous experience with Racerstar motors, I have decided to bite the bullet and order them.
The Racerstar BR2307S 2500KV arrived in regular Racerstar motor paperbox packaging protected in bubble wrap. There were no extras in the box except for a nylon bag with 4X M3x8 and 4X M3x6 motor screws.
It seems that Racerstar stopped the practice of offering CW and CCW motors and from now on they are only offering CW ones. Anyway in my experience, the previous models as BR2306S the CCW ones had problems with the build quality.
Overall look and quality
These are very nice looking motors and they look exceptionally good when mounted on a miniquad. The overall build quality seems similar or a bit lower than the one on BR2306S, there are small dents on the bell edge, the anodizing of screw nuts seems like unfinished. Maybe this is due to the fact that this is first series of these motors but it is worth noting. It looks that these motors are painted instead of anodized. There are visible traces on the motor screw nut and at the motor bottom.
One of the things that I have found to be improved is the bearing quality, all 4 motors have decent bearings and no vertical movement on the bell.
The magnets that are used in these motors look lake the ones used in BR2306S. They aren’t curved and the air gap has considerable height.
The windings seem to be machine filled with multi-strand wires.
The motor wires are 7cm long which is unfavorable for a builds with 4in1 ESCs where you should put some extra effort in extending the wires.
The motor weight is 37 grams with the wires, probably 34 grams with shorter wires on a normal build with 4 ESCs.
The height is 34mm and the width is 28.5mm
I have yet to test these, and I’m going to install them on one of my KISS builds tonight as soon as I finish this post. They should serve as a replacement for Emax RS2205 2300KV so on paper they should be a considerable improvement. I will update this post with my impressions.
You can buy these motors here
Pros and Cons
Pros: Cheap great looking motors, for budget builds or for race practice. No play in the bell and the bearings are smooth on all 4 motors that I have got.
Cons: Build quality seems similar or a bit lower then previous models. The motor seems painted and not anodized. The motors use C-clip. It would be great improvement to see the similar motors with a screw instead. There is considerable airgap between the magnets and the stator. They seem a bit heavy and the wire length is not suitable for 4in1 ESC builds