Choosing new motor and lipo.

[microdiladum]

I am in the market for a new motor. Currently have a 18.97KWF and Faigo 10L on 14 cells. Wanting a higher end motor. Looking for either a Lehner or Pletty motor. Thinking a Lehner 1940 series or Pletty Bigmaxximium. Also wanting to get some Kokam lipos. Wanting one Kokam 3200 3s and another Kokam 2s 3200 wired in in series to make a 5s pack. Possibley considering a 6s if my 18.97 can handle it, but would rather not puch its limits.

So what I need help with is choosing a Lehner 1940 (Or other) motor that is approriate for 5s and will not exceed the 64 cont amps the Kokam is rated for with the right gearing? Is this possible? My 10L could do that couldn't it since it is rated at 61 amps? What about the pletty bigmaxx? If it helps the truck is a 10-11 pound truck. I want my controller and motor to run cool and def dont want to fry my expensive Schulze. The 10L stays just warm. Would I be able to keep amps and heat lower if I choose a motor for and use 6s packs? Anyone know if the 18.97 can handle a 6s for sure?



Thanks to anyone that can help and if I have forgetton any info let me know. Still kinda new to lipo and brushless.

[MetalMan]

There is a lot of talk about the Feiago 7XL. It can take 5s Lipo very well. The amp rating of a motor has nothing to do with the number of amps it will pull in a vehicle. Brushless motors rated for 50amps can burst past 100amps given the chance to. Usually they pull fewer amps continuously.

One thing to keep in mind since you say that you want to go Lipo is that you will need a LVC device (low-voltage cutoff). This basically cuts the power/reduces the power to the motor when a cell gets to 3v. The idea is that it will prevent damage to the cells and possibly prevent any damage.

[microdiladum]

Originally posted by MetalMan
There is a lot of talk about the Feiago 7XL. It can take 5s Lipo very well. The amp rating of a motor has nothing to do with the number of amps it will pull in a vehicle. Brushless motors rated for 50amps can burst past 100amps given the chance to. Usually they pull fewer amps continuously.

One thing to keep in mind since you say that you want to go Lipo is that you will need a LVC device (low-voltage cutoff). This basically cuts the power/reduces the power to the motor when a cell gets to 3v. The idea is that it will prevent damage to the cells and possibly prevent any damage.

I have though about the 7XL on 14 cells. Not comfortable running the 7XL on 5s. Just think that would be to hot for me. Looking for a cool running system. Mabye a 8XL on 5s would be better for me, but I am not really looking for another faigo.

Also I do understand that there can be burst of 100+ amps on a 64 amp rated motor. I am really looking for information on the possible cont amps being pulled by these motors. So what exactly is the amp rating on the motor mean?

So I guess what I was really asking as for advice as to what motor I can use that will overheat or worse fry my controller and my lipos.

My schulze controler has a LVC device built into the controller for use with lipo batts. So dont have to worry about that.

[MetalMan]

The amp rating on a motor is just its nominal amperage. You can figure out how many amps are pulled average by the motor. Divide 60mins. by your run time, and then multiply that number by the capacity of your battery. So, let's say you got 15mins on 4000mah. That means that the average amp draw would be 16,000ma, or 16amps. Basically, continuous amps drawn in a monster truck might be 15-25amps depending upon the motor. But high amp bursts are the reason why batteries will heat up.

Do you mean to say "whatI was really asking as for advice as to what motor I can use that won't overheat or worse fry my controller and Lipos."?
If it is, you could go with a 8XL on 5s Lipo. You would get very good runtime with this setup, and it wouldn't be too hard on the motor, controller, or batteries (not much heat). If you want to spend as little on batteries as possible, you could probably use batteries that are rated at 40amps continuous in this setup.

[squeeforever]

the polyquest 6000s are rated for 93 continuous amps. and a 2s 6000 is only like $125.

[microdiladum]

Originally posted by MetalMan
The amp rating on a motor is just its nominal amperage. You can figure out how many amps are pulled average by the motor. Divide 60mins. by your run time, and then multiply that number by the capacity of your battery. So, let's say you got 15mins on 4000mah. That means that the average amp draw would be 16,000ma, or 16amps. Basically, continuous amps drawn in a monster truck might be 15-25amps depending upon the motor. But high amp bursts are the reason why batteries will heat up.

Do you mean to say "whatI was really asking as for advice as to what motor I can use that won't overheat or worse fry my controller and Lipos."?
If it is, you could go with a 8XL on 5s Lipo. You would get very good runtime with this setup, and it wouldn't be too hard on the motor, controller, or batteries (not much heat). If you want to spend as little on batteries as possible, you could probably use batteries that are rated at 40amps continuous in this setup.

Ok thanks for the info. I will keep the XL faigos in mind but like i siad I am not looking for another Faigo motor.

Mike, I heard you say before tha you use the Lehner 1940 series. Could you help me out a little with which one to choose and if I can safetly use the lipos?

[microdiladum]

Originally posted by squeeforever
the polyquest 6000s are rated for 93 continuous amps. and a 2s 6000 is only like $125.

Yes but those are WAY to large for my chassie.

[Serum]

Okay, first of all;

The 1st step you wanted to make with the 6S is huge, compared to the 14 cell powered 10L you first had, here is why;

-lipo will be much lighter
-you run at higher volts
-you use a stronger motor.

Those 4 points make me want to say 'use 5S lipoly'

Considering Promod did nearly 60 mph (59.7 mph) on his 2240 powered truck and a 6S lipoly. In other words.. BE PREPARED! you know what lipoly's are up to. Who's Promod? A high speed guru, and also a complete scientific one (practical science) he used that 6s setup on a schulze 12.97......... (that first 12 doesn't stand for the max amount of lipo's but for the max amount of nimh's or nicd's...


My choice for a nice runtime vs speed would be in the area of the 1940/8 or 9 The nine for the coolest setup and a longer runtime and the 8 for a topspeed setup.. (mind that those RPM ratings are under load)

I would stay away from a bigmaxximum. The schulze is a rather sensitive controller (understatement) and a 4 pole is about twice as hard on your esc than a 2 pole motor.

[microdiladum]

Ok so 1940/9 it is on 5s. But the big question is will the Kokam 3200's handle the cont amps and the burst? Anyone with experience?

Mike are you there?

[RC-Monster Mike]

I am here! I use the 1940/8 motor on 5S and 6s Lipo, using the Kokam cells you mentioned with no trouble at all. Even on 6s, the motor runs relatively cool and I could complete a 10 minute main with no trouble - I could go longer with these 3200s. On 18.5 volts(which is where I would limit myself with the Schulze controller), this motor is excellent and will provide plenty of cool running, smooth power. I have actually considered using a 19470/7 for 18.5 volts, but the 8 turn works perfect with 5s or 6s. I don't use a LVC device, either, though I agree ethat it is a good idea.

[RC-Monster Mike]

Nice truck, too, Micro!

[microdiladum]

Thanks Mike! Just need to pick up one of those gmaxx chassies and I will be really happy with it.

Just sent you a e-mail about some pricing on that 1940/8. ;)

Also gonna pick up the 5s lipos first so could I also use them safetly with my 10L too?

[RC-Monster Mike]

Depending on the circumstances, the 10L will work with the 5s Lipo. It will need cooling measures(fan) and the appropriate gearing, but it otherwise works quite nicely on 5s Lipo.

[RC-Monster Mike]

I haven't received an e-mail yet, though.

[microdiladum]

I sent it through your "Contact Us" form from your homepage. Should I do it again?