Chosing a motor

[Reddley]

Hello. Recently I transferred my velineon power system to my trx4 after its own system went out and ordered the castle sidewinder 3 with 5700kv brushless motor combo for my rustler 4x4 vxl and bought a 21t pinion in the hopes for 70mph, but I was severely disappointed as the motor is so weak it cannot handle even the stock 11t gear and was told it was strong enough to through the stampede 4x4 around like a rag doll. On the 17t gear the rustler only reached 55 vs 58 stock motor and overheated immediately and i need help choosing a new motor and esc separate or combo under $200 that will be capable of at least 65 mph on a 21t gear (smaller tires is why I chose the 21 over 20t gear) and achieves this on a 3s battery, 4s if i have to though.

And so I know what kv motor is best all around for 4x4 bashing and 70mph speed runs?

[RCWilly]

5700kv is very high especially for a 4x4 with large tires. The stock Velinion motor is 3500kv which means that it has much more torque, but less speed. High kv motors overheat easily on heavy loads, which is why it seems weak. They are ideally used for light 1/10th scale 2wd trucks and on-road cars.

I'm not sure about which motor to get, since I don't really worry about speed, but maybe someone else can point you in the right direction

[Reddley]

Thanks for the info!

[afreek1000]

Hobbywing

This combo would be nice.

https://www.amazon.com/38010200-Max1.../dp/B073DCT1X8

[Reddley]

Thanks, ill look into this one

[afreek1000]

I run hobbywings in my X Maxx and they preform great. Loads of power.

With the model I suggested, you may have to gear up to get more performance/speed if that’s what you’re looking for.

As RCwilly said the stock motor is 3500kv. The hobbywing is 3200kv. So it will deliver more torque but it spins at a slightly lower RPM than stock. Gearing up will bring it to a closer final drive ratio of what stock is.

You will probably have to experiment.

I’d suggest a starting point of maybe 14/54 pinion to spur ratio.

Going higher and that, say 15/52, will give you more space

[StijnH]

Hobbywing

This combo would be nice.

https://www.amazon.com/38010200-Max1.../dp/B073DCT1X8

I have this combo in my Stampede 4x4 (14/15 x 54) and my Slash 4x4 (17 x 54).
I'ts geared for use with 2S.
I could gear even higher on my Slash 4x4, but I like it as it is.

It's a good combo, much torque and plenty fast for the places I drive.
I second that a 14t /15t pinion would be a good place to start.

But I doubt that you can get 70mph with this combo.
If that's the speed you want, you'll have to go even lower on KV.
70mph is fast for a Rustler 4x4. It will require some serious upgrades to get there and can be an expensive route.
Enjoy it !

[olds97_lss]

The 3660sl tends to run on the warm side. I've had better luck with the max10 sct and a hobbystar 3665 3100kv motor. Would probably be better yet with a 3670.

Either way, with that esc, you have the option to run 4S or 3S. The 3100kv may run a bit warm on 4S, but you can get lower kv versions of it.

https://www.rcjuice.com/hobbystar-36...aterproof.html

If you have room, the 3050kv 3670 is rated up to 5S, so 4S shouldn't be an issue with it:
https://www.rcjuice.com/hobbystar-36...aterproof.html

Either way, if your pushing it that hard, I'd suggest a motor fan.

I run the max10 sct/3665 3100kv in my eJato on 3S... I just bash in the grass and at skate parks. I can't get it to top speed in the grass, it just flips on me. Recently only running it in the grass with the new tires I put on the rear. Was running 2.8 trenchers, but just spun the wheels a lot, so tried a set of duratrax faze mt's... now it hooks... and wheelies constantly. lol!

I originally had the system in my stampede 4x4 and it did fine on 3S, but I wanted a bit more torque and a bit lower temps. Ran on the warm side, but was still within a safe range. I ended up going with 1/8th esc and 4074 2200kv motor in that.

Takes a ton of run up to get speed without pulling a wheelie or crashing, but it's still a lot of fun:

[Dcuda69]

I have a 3674 2700kv that I run in my Slash 4x4. I geared it 20/54 on 3s was crazy fast...on 4s it thought it was an airplane. At that speed aerodynamics become the challenge! That can size/kv range is a great fit for these trucks(not sure on fitting a 74mm long can in the Rustler chassis...fits great in the Slash)

In my Slash

[bennobee]

Hobbywing

This combo would be nice.

https://www.amazon.com/38010200-Max1.../dp/B073DCT1X8

I have literally just installed this combo and paired it with a 3S battery. Its INSANE how much more fun it is and much less problems that the stock motor n the VXL system.

[Reddley]

Just ordered the 3200kv combo and a new 5mm pinion set for it, cant wait!

[Reddley]

The 3660sl tends to run on the warm side. I've had better luck with the max10 sct and a hobbystar 3665 3100kv motor. Would probably be better yet with a 3670.

Either way, with that esc, you have the option to run 4S or 3S. The 3100kv may run a bit warm on 4S, but you can get lower kv versions of it.

https://www.rcjuice.com/hobbystar-36...aterproof.html

If you have room, the 3050kv 3670 is rated up to 5S, so 4S shouldn't be an issue with it:
https://www.rcjuice.com/hobbystar-36...aterproof.html

Either way, if your pushing it that hard, I'd suggest a motor fan.

I run the max10 sct/3665 3100kv in my eJato on 3S... I just bash in the grass and at skate parks. I can't get it to top speed in the grass, it just flips on me. Recently only running it in the grass with the new tires I put on the rear. Was running 2.8 trenchers, but just spun the wheels a lot, so tried a set of duratrax faze mt's... now it hooks... and wheelies constantly. lol!

I originally had the system in my stampede 4x4 and it did fine on 3S, but I wanted a bit more torque and a bit lower temps. Ran on the warm side, but was still within a safe range. I ended up going with 1/8th esc and 4074 2200kv motor in that.

Takes a ton of run up to get speed without pulling a wheelie or crashing, but it's still a lot of fun:

Thanks for the advise, I ordered the 3200kv one and I also have a fan for it and a new set of pinions to experiment on which is best for bashing and best for speed runs.

[Reddley]

I have a 3674 2700kv that I run in my Slash 4x4. I geared it 20/54 on 3s was crazy fast...on 4s it thought it was an airplane. At that speed aerodynamics become the challenge! That can size/kv range is a great fit for these trucks(not sure on fitting a 74mm long can in the Rustler chassis...fits great in the Slash)

In my Slash

Pretty nice setup! I ordered the 3200kv to be on the more cautious side of things and I'm hoping it will be able to handle the 21t pinion unlike the velineon motor of mine. If not I bought two sets going from 11t to 21t of pinion to experiment, so fingers crossed it works much better!

[olds97_lss]

I have a 3674 2700kv that I run in my Slash 4x4. I geared it 20/54 on 3s was crazy fast...on 4s it thought it was an airplane. At that speed aerodynamics become the challenge! That can size/kv range is a great fit for these trucks(not sure on fitting a 74mm long can in the Rustler chassis...fits great in the Slash)

In my Slash

What motor is that? PM me a link? Wouldn't mind shaving a bit of weight off the stampede for a motor that is proven good. Between the 1/8th esc, 4074 motor and 6200mah 3S lipo... my stampede is a bit of a pig!

[Dcuda69]

What motor is that? PM me a link? Wouldn't mind shaving a bit of weight off the stampede for a motor that is proven good. Between the 1/8th esc, 4074 motor and 6200mah 3S lipo... my stampede is a bit of a pig!

Sorry. That's a Kershaw Designs motor and it's no longer available. Couple of us on the board here stumbled across them a few years back. Great fit in the Slash. A bit longer than the Castle 2400kv and obviously a bit higher KV. Also has a 5mm shaft(unlike the 2400kv Funny Car motor) I bought 1 new and then stumbled across a lightly used one on Ebay so I snapped that up as well.Slash is currently running a 4074 2150kv but it's coming out and the Kershaw is going back in. Leopard used to make a similar motor but I'm not sure they still do or if they're still around.

[olds97_lss]

No problem. One of these might be worth trying to drop a bit of weight and pick up a few rpm's for 3S running vs the 4074/2200kv I'm running:
https://www.ebay.com/itm/3674-2450KV...C/233271952058

Kind of a no-name 3674/2450kv motor. Looks like the hobbystar ones.

[Dcuda69]

No problem. One of these might be worth trying to drop a bit of weight and pick up a few rpm's for 3S running vs the 4074/2200kv I'm running:
https://www.ebay.com/itm/3674-2450KV...C/233271952058

Kind of a no-name 3674/2450kv motor. Looks like the hobbystar ones.

Might be worth a try.....the 4074 2150 that I'm running now is a no name motor..paid $40 for it. It's torque monster! That Kershaw still has enough torque and is a bunch faster