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What Size Bullet Connector ? (noobee question)

Fond a couple of Brushless motors that came without bullet connectors. Looking at the FT brushless motors it appears that there are several sizes of connectors and being a noobee I have no clue. These are identified as BR2212 2450KV motors.

So is there a standard for sizing the male bullet connectors for the motors.

If there is some reading material - point me toward it.

Noobee In NW Ark.


Well-known member
There is no standard sizing of bullet connectors. They do come in sizes relative to the amperage rating of the motor they are on. Smaller power motors have smaller connectors.
I got sick of having lots of different sizes so you can just pick a larger size for everything or use these excellent motor plugs instead. The only disadvantage to these is you need to get the motor direction right first as you can’t swap the leads over as easily.


Well-known member
I use EC3 connectors on all my batteries and ESCs. They are the blue Eflite connectors. The internals of the EC3 connectors are 3.5mm bullets, which are commonly used on motors that fit FT sized planes. I buy the EC3 connectors in bulk, and have plenty of bullets for motors, ESCs, batteries, etc as everything is the same size.
Thanks, the motors are cheapo racerstar things. ($5.67ea) x 3) I will probably look into getting an assortment of connectors and what you say about sized generally based on Amp draw is pretty common sense. I was hoping that there was some sort of industry (?) Standard but sounds like I'll need to invest in an assortment and keep the iron hot to change if needed.

Looking more closely I guess the correct term is really 'banana plug' (?) - gold plate with cuts to allow compression when pressed into other connector.

Thanks for the quick answers. (fm a 70 yr old noob - finally getting to fulfill a dream from the teen years with the old control line Cox planes.)


Well-known member
Banana plugs are slightly different to bullets, they have more flare in the Male connector and are a bit bigger. They are often used on charger output leads.
I would just pick a connector like the Amass ones or the EC3 and fit it to everything, I do that with all my ESC’s and batteries. All my batteries are XT60.
Soldering bullet connectors is harder than both EC3 and Amass type ones plus there’s more risk of a short with them if the heat shrink doesn’t fully cover the connector body.


Well-known member
It’s such a tiny weight difference, I couldn’t be bothered with lots of adaptors for my charger etc.


Well-known member
@Scottand5sons XT60 on batteries, EC3 or Amass 3 ways on motors/ESC.
@MacClarkNC I always say to use what works for you. Bullets are fine but are not very tolerant of mistakes like dry joins or insufficient insulation. I have them still on a few things. They are handy for changing motor direction.


Well-known member
Depending on the plane especially small and micro planes I solder motor leads direct to the ESC, as I figure the smaller motors and ESC`s will stay together, and easy enough to unsolder if need be ( weight savings ).
The thing I like about the hobby is you are always adapting to what you have on hand. Now that I chose xt30 for my mini batteries, I have to make a charger adapter rather than order one when I noticed my harness is missing this size


Should work, looks like 1/32 gap, electrical tape strip should add protection from short. Just adding this to the bullet thread since you run into this type thing when you use more than one set of connector sizes.



Well-known member
I prefer a little wire between the plugs, that way you can properly insulate the contacts. One drop of water or a dropped metal object at the wipeout angle and that is going to short. I never have bare metal anywhere near my charge set up or batteries.
You could make that safe with epoxy putty in the gap or at a pinch hot glue, but that can get liquid again if it gets hot.
I agree, thought about some hot glue between but decided a couple of strips of electrical tape between the terminals may insulate it. Finished plug ended up very rigid. I only plan to use it to charge 7.4 batteries and never charge unattended.