Some problems that need fixing

So, I ordered all my parts, but there are some problems. Looking back I have to wonder “Why was I so dumb?” Anyway…

1. Bullet Connector This one isn’t that big of a deal as I know there are adapters out there. My VESC bullets are 5.5mm and my motor is 4mm. I found some on eBay, but they are $8.49 for one (I need three). I would rather not pay that much. Does anyone know of some cheaper ones?

2. Motor Shaft This one might be a problem. So, my pulley bore is 6mm, my motor shaft is 8mm. I bought my pulley from SDP/SI. I knew I wanted 13T, 5mm pitch. The only option for 15mm width (which I decided would be more reliable especially up hills) was 6mm bore. I wasn’t thinking and bought it. What do you guys suggest I do?

3. LiPo BMS This one isn’t a problem really, just something I need advice on. I was inspired by @Namasaki to do a 5x 2S LiPo BMS build. I bought 2S2P, but Namasaki told me that isn’t the best idea because then the BMS will only watch each parallel pack instead of all the cells individually. Should I return it and buy 2S1P?

Oof, that’s the end of it… for now. Hopefully my stupidity doesn’t hit you guys through your computer screen :sweat_smile:

Feel free to be tough, I have a thick skin. And also if you need anymore info, just ask.

The easiest way is to just buy a set of either 4mm or 5.5mm bullets and resolder so you get the same connector on both sides with no need for an adapter.

Unless you got the tools and know-how to drill out a bigger hole in your pulley, buy a new one with the right bore size from one of the known e-skate vendors, most have a 15mm option.

From a safety standpoint, using 2s1p packs is the better choice. With the 2s2p you run the risk of one cell in the parallel set going bad and getting overcharged or discharged due to unbalancing of the two cells, which is bad.

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  1. Just solder 5.5 mm bullet connectors from hobbyking on the motor , i use them, they fine!

  2. A) get another pulley B) Use press drill to make that hole to 8mm, to be more safe start with 6,5mm then 7mm then 7,5mm then 8mm

Since you already have 5.5mm bullets on your Vesc phase wires, change to 5.5mm on the motor wires. 5.5mm bullets are much better than the 4mm. The 4mm tend to work loose while the 5.5mm hold solid and a tighter fit means less resistance. Send the 2s2p lipos back if you can and get the Turnigy 2s1p Lipos hard packs.

@ninja @Iceni I could in theory drill a bigger hole, but my worry is that it will be off-center. And I would buy an other pulley but most vendors are too far away (shipping costs) or don’t have what I want. May have to just very carefully drill it…

With metal lathe it wouldn’t be a problem if you can get hands on it. With press drill it also can be done good, just make sure you fix that pulley good and in level. check it 7 times before drilling. I’ve used claws from metal lathe

to hold my pulley when drilling hole in it, with those claws pulley stays in perfect level. Then drill. Better start with 6,5,- 7,0 - 7,5- 8,0mm

But also there is option use aluminum pulleys from e-bay something like this

So why you need 13t? what your wheel diameter and wheel pulley.

I have 15t 15mm motor pulley with 8mm bore and keyway in steel which lasts much longer than aluminum motor pulleys pm me if interested

I too bought 6mm ID pulleys from SDP/SI and bored them out to 8mm. Not sure why 6mm is the max diameter they have for 15mm belts… But anyway, you need a lathe to do it properly. It only takes a minute. A local machine shop might do it for free since it’s super simple

You can also do it on a mill, but make surely it’s perfectly centered

Lots of hills in my area, need some good torque. Wheel diameter is 83mm, wheel pulley 36.

So you went to a shop? Or you did it yourself?

Hey! I can send you some male 5.5mm bullets for free if you want to pay for shipping. I can probably send them in an envelope to make it cheaper?

No problem. Already got it covered. Thanks though. I know you guys offer different connectors on your VESCs but wasn’t thinking :joy:

Yeah I did it myself because I have access to a full machine shop. I made my own pulleys on a lathe and knee mill

But boring out the motor pulley would take a machinist less than a minute

No problem! Just wanted to get you up and running.