Focbox 3.5mm bullet connector to 5.5mm motor connector

What are people doing to get the focbox 3.5mm female bullet connector to connect to the 5.5mm female connectors on the 6374 190KV motors??


Strip the heat shrink off the 3.5s, fill the 5.5 with solder, stick the end if the 3.5 in the solder. Works perfect. Thank @longhairedboy for the tip :grinning:.


you know what… I think I just learned something… depending on what company you buy the motor from will determine the connector type?? sorry im crazy new to all this and trying to learn

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No worries, everyone is a noon at some.poi t. Just part of the process.

The FocBox’s have 3.5mm bullets because the hub motors enertion uses has 3.5mm bullets. Almost everyone else uses 5.5, but the 3.5 are good enough for 90% of the builds out there.

im super noob right now but im having a great time learning… what do you think if I just soldered a 3.5mm male bullet connector to a 5.5mm male bullet connecter… that should work right? so after soldered together it would just be able to slide right into each female ends

I’m not sure what you mean, I would just do it like I outlined above…fill the wire side of 5.5 with solder and pop the 3.5 in it while it’s hot. Then reapply heat shrink.

Or you could talk to @GrecoMan or @scepterr, either one could make the adaptors you need.

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Sorry to revive an old thread but I have the same issue on my current first build.

@Danny414 what did you end up doing? I don’t think my 3.5mm bullets fit in my 5.5mm bullets. I can strip the heatshrink off the 3.5mm bullets but I don’t think it’ll make it fit, the heatshrink is very thin on the foxbox wires.

@mmaner I think he means to solder the 2 male heads together (should this be done with wire inbetween or without) and use it as an adapter basically, which i was thinking of doing too because then it is more modular and easier to take out if necessary.

Why not only to change the connectors on your motor cables to 3.5. No need to touch the focbox, no lose of warranty :see_no_evil::joy: Crazy that the warranty will end if you change the bullet connectors.

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I ended up soldered them together to make an adapter… I just did that because I didn’t want to void any possible warranty with the motor controller or motors if they failed. It worked out great. That was months ago and I’ve had no problems

Ok I think I’ll try this, did you put wire in between them or no?

@Andy87 I’d rather avoid changing anything on the motor wires or focbox wires to not have any issues with warranties

@SeanHacker I don’t understand what you did sorry can you explain. You stripped the ends of the focbox then just soldered them into the female connectors on the motor?

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Nope, no wire… I had to bend some of the end of one of them off so it sits flush against each other… I just used flux and it worked great!

You can cut off the 3.5’s. Strip the wire. Solder on the size bullets you need to use. Done deal. Very easy.

Check it out. I made one quick for you buddy

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Looks good! I’ll probably go with that, just need to find somewhere to get bullet connectors quickly haha, build is almost done and don’t want to wait ages for Chinese shipments.

Thanks for the help everyone

I found a local hobby shop that did rc cars… also amazon has them. Prime it baby!

What are you making? Up some pics

Might cut away the 3.5mm connector and solder a 5.5mm instead. The lesser bulk, the cleaner, and better…! Right? :thinking:

It voids the warranty for the focbox. If you don’t care about that then ya by all means its probably the best solution

oh, what? did i void 2 warranties 2 days ago?