Need Help lol New to Brushless / Lipo's

[Twiztid Metal]

Alright although iv done some searching around and have found alot of info nothign id straight forward to me. Not sure if im understanding wrong or what.

alright I got a good deal on a Novak Goat system with 17.5 Motor and a 2S 3300 Hyperion Lipo battery and Dynaimate charger.


First the MOTOR Ratings. I am so used to brushed motors and how they work lower turns mean more speed and high turns means more torque.
The KV ratings throw me off too.

IS THIS THE SAME FOR BRUSHLESS? Where could i find a comparison of say a 15t brushed motor compaired to a brushless? I know brushless is compleatly differant and Its given my stampede a hell of a work out thus far.

and why is it that the NOVAK Goat system can handle down to a 8.5 Brushless set up and only down to a 27T Brushed set up.

Next is LIPOS i can only run a 2s on this system, what would the same battery at a 3S AND 4S make as a differance? more run time? more power?

I know its all been asked befor but I just cant fine the CUT THE CRAP Straight forward talk.

Help me out, thanks guys!

[Twiztid Metal]

16 views nobody knows a thing huh.

ok make it simple

21.5=slow?


8.5=fast?

[1rcmonster]

On the lipos a 2s has one less cell than a 3s and two fewer cells than a 4s. Also the voltage is less on a 2s versus the 3s and 4s, a 2s is 7.4v, 3s 11.1v, 4s is 14.8v. I have read where some are running 3s on their Goat 2s systems, I for one would not do it, not a big fan of burning up electronics.

As for the brushless motors I can't help you there. I have a few brushless trucks, but they came that way, and I haven't seen the need to change them.

I am sure there is a chart somewhere of what brushless motor equals what brushed motor. Try googling it...

[neillarson]

First the MOTOR Ratings.

FIrst thing to understand is that each manufacturer has their own interpretation of motor ratings. you are correct on the turn count, the lower the turn count, the faster the motor. The KV rating is the opposite, the higher the rating, the faster and the lower the number, the more torque, BUT, each vendor makes their own decisions on what to rate their motors at but are generally close. Novak says a 21.5T is a 1800KV and a 17.5 is 2200KV. All manufacturers that rate their motors in turns list a KV rating so you have something to compare.

When you are shopping for motors, you also have to understand their cell capability based on the ESC you are pairing it with. For example, the Castle Sidewinder with a 5700KV can only handle 2S while the same ESC with a 4600KV can handle 3S. For a crawler, I would ONLY consider systems that can handle 3S and up. Also, for a crawler, if you are going brushless, stay away from uncensored motors unless it is a purely trail truck because of the tendency to cog badly at low speed. so they really can't crawl.

IS THIS THE SAME FOR BRUSHLESS? Where could i find a comparison of say a 15t brushed motor compaired to a brushless?

There are charts all over the internet if you google them and they all differ, but in general, what used to be called a Spec motor in brushed was a 27T and in Brushless is usually in the 19.5T area. Stock Brushed was a 29T while the brushless version is a 21T

and why is it that the NOVAK Goat system can handle down to a 8.5 Brushless set up and only down to a 27T Brushed set up.

This is one for an engineer that has spent more time on small motor systems, John R Holmes is a GREAT resource for questions like this but he is a busy man so don't expect an overnight answer. There are others on the board that are very good. I would hazard to guess the difference is the start up current needed and the efficiency of the motors.

Next is LIPOS i can only run a 2s on this system, what would the same battery at a 3S AND 4S make as a differance? more run time? more power?

It is all about voltage and the ability to sustain a consistent current output. 3S is the most common crawler battery, while 4S are rapidly becoming a standard. Seldom do you see 5S or 6S just because of the bulk. Speed/power is based on the number of sells, run time is based on Capacity or MHr rating. So, again, in the crawler area, you see a lot of 800MHr and 1300MHr in the comp trucks, and 1300MHr and 2200MHr in the scale area. In the go fast arena, 3300MHr and up (all the way to 10000MHr for 2P (2 parallel)) provide higher run time at the sacrifice of space and weight. A 5S2P 5000MHr battery looks like a small brick and weighs as much. if you are unfamiliar with the labeling scheme is 5S(5 cells in Series)2P(2 sets of those 5 Cells wired in parallel)

Hope this helped and didn't confuse you.

[Twiztid Metal]

Hay Thank Neil. I know its alot to type out and explain but I really do appreciate it. Iv tried googleing and I ended up with mixed results thats why I came here. I did notice the KV rating changing from motor to motor on manufactures which is really confusing. It should be a standard rating like Brushed motors are.

I dont plan to go Brushless on crawler/scalers I was looking into the info because I finaly got a brushless set up and never had one. Its going to be mainly for bashing reasons. Just wanted to know which direction I Should go in. the 17.5 Seems to have lots of torque on 2s which I am fine with, alot more funner than our 7cells we have been running. I do like speed so Now that you helped me out Im thinking of getting a motor that can handle a bit more speed. So im gona drop down a few turns and get some more speed and still have lots of torque for our trucks. So im guessing something along the lines of a 13.5 or 10.5 would be awsome.

On a side note, I do like brushed motors in my crawler and scaler, very smooth and predictable and I like the added weight the battery gives me up front and pleanty of run time.