Talk 1520 - your experiences

[Jahay]

i would love to get that 1520... but for the speeds i want to reach i think it spins too low... 1518 will be better for me. I bet the 1520 just has way to much torq!

[ANGRY-ALIEN]

Originally Posted by Jahay

i would love to get that 1520... but for the speeds i want to reach i think it spins too low... 1518 will be better for me. I bet the 1520 just has way to much torq!

No one is saying you can't reach 'those speeds' with a 1518... all we are saying is that the 1520 will get there with a little efficiency... 1600kv is not that low... as said before, if you gear it appropriately it will still do the job.

From Wikipedia: 'Torque, also called moment or moment of force, is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist.'

So, the higher 'moment of force', the faster motor will achieve it's "twist'... which translates to greater acceleration and getting to 'top speeds' quicker...

See the comments below:

Originally Posted by RC-Monster Mike

"The 1520 is plain overkill unless you have a 15lb truck with big aluminum rims or something.")

Originally Posted by nuz69

"Hello Jahay.
Anyway, the 1520 would be the best choice for your application, because it can handle more power than the 1518 and had always an higher efficiency.
Where the 1518 works good, the 1520 works just better in truck and truggy."

As the thread name says, '1520 - your experiences'... I can only really speak to the 1520... but I am sure the numbers also speak for themselves... I too believe that the 1520 is overkill,
but that's what i love about it.

Alien

[Jahay]

angry alien... looks like i will go with the 1520...
The 1518 is out of stock everywhere.... I will just gear it a little higher when i want to do speed runs... and im sure ill enjoy the torq when gearing lower for bashing...

Thanks for the advice... really appreciate it

[ANGRY-ALIEN]

No worries man...

[nuz69]

:o















:)

So happy to finally get it ! That was quick, US ==> FRANCE : 7 days :D :D

[ANGRY-ALIEN]

mmmmm... I love that new motor smell

[nuz69]

The tekin truggy and other "truggy motors" just cant match with this little 2000 Watts monster !

[itbvolks]

Not sure they're not trying too...

I guess I don't necessarily follow the bigger and bigger motor theory. Sure it makes more power so you see less peak current draw but at the end of the day, it still requires motor current just to run it due to it's size and the field required to run it... Otherwise, we'd just run the 1717 or bigger and call it a day.

I'm pretty sure the constant uncontrolled wheel spin doesn't help your lap times either so whatever small efficiency gain your getting is lost while your not turning faster laps It's certainly not like the tekin's are considered underpowered.

It's like saying running big block nitro motors is more efficient because they make a ton of torque so you can gear them up, requiring less rpm and thus allowing for more run time per tank... I have yet to see that work out.

Certainly, a more powerful motor has to work less hard to get the vehicle to speed but there is also a point of diminishing returns. There is something to be said for easy to drive....


Maybe I'm completely wrong here and I'll get one and see for myself but I guess I don't see where the benefits would be here. That being said, Nuz, if you come back praising this thing and you picked up 3-4-5min run time even with the taller gearing and the temps are icy cool, I could see me picking one up for sure...


Just sayin

[nuz69]

I bought this motor for its efficiency, not its power ! Its the motor that will give me the longest run times with my truggy application and the lower amp rate with his low kV !!!
I do not attend to use it like you US bashers with your 65mph monster truck wheelings and other crazy stuff
For exemple, i will gear it first for 40 mph, not more :D And myabe later, i will try some 22-25 pinion gears to push the motor (or the truggy) to its limit

[itbvolks]

Hahahaha!!!! Basher....??? Clearly your misunderstood.....

Anyhoo, my mbx6t is 9.3lbs ready to run in full race trim as it sits right now. With my tekin 1700kv it's geared to do your exact race spec 40mph (15-16/46).

I want to run 20min mains on my 4200mah setup. I'd run a 5000mah but it's 101grams more mass. 5500's are another 171gr over the 5000's (272gr total over the 4200's). Not worth the weight increase for the capacity gain. I could go down in capacity and deal with a batt change but the mass difference between 4200 and 3300 is only 40grams and less to the 3000's, so again, not worth the sacrifice. Doesn't make sense to drop more capacity to save that little weight.

Now if we look at the weight difference between the 2 power systems we get more interesting info (for those of us bashing and all )...

MMM/1520 combo - 603gr

RX8/TT2322 combo - 480.5gr

Difference of another 122gr or a 27% It's my belief that a lighter setups with well sorted driveline is worth more efficiency (wasted diff or wheel bearing will kill your efficiency). Takes less current to get it to speed, etc. Matter of fact, the slipperential I installed is on my short list already. It may provide driveline protection and some tuning options but it's much heavier. I'm planning on trying the delrin plastic gear to reduce the mass but a plastic geared stock mugen diff wouldn't weight beans by comparision. I'll be weighing the benefits closely once I get my setup on the track...

Like I said, I'm not saying it's not a good, viable option. It might be a great setup out there. Goodness knows I love power to spare (heck, I ran a Rody C5R in a truggy before). I'm just not sure this buys me anything. I could just as easily run a 1300-1500kv tekin on 6s for efficiency sake... All that being said, if you come back with great efficiency gains and cool running animal, I'm all in...


< --- Clearly a well developed bashers setup

[itbvolks]

Not to dissuade anyone from looking at the 1520. I think it's going to be a GREAT motor especially for those looking to build complete land animals. I think Castle makes great stuff and I'm sure this will be a great powerplant.

[nuz69]

I didnt say that your tekin truggy wasnt efficient. But the tekin truggy motor handle already less power than the 1515 1Y castle (1400w vs 1500w for the castle). It means that your tekin will virtually run hotter than a CC/neu 2200kV. As my opinion it will run as cool as a CC 2200kV because its lower kV and 5S.
But here in Europe, we stated that a 1500W motor is a little weak for truck heavy like monster or truggy, at the end of one run, the motor often rises to 150-160 °F with a tekin truggy or a CCneu 2200kV. And thoses high temps will literally kill your efficiency...
I started with a 1000W ORION combo 2050kV in my stock inferno VE, my runtimes was about 15 min with 150-160°F in the motor. I bought then a CC 2200kV combo, and i am now at 100°F max with 65-70°F outside and 20min of runtimes !!!
==> That mean a motor which can handle a lot of power consume less amp than a small motor that is pushed to its limit. A motor which can handle more power dont consume more amp than a smaller motor (there is a limit too, full throttle all time wil consumme more with a powerfull motor ^^^). Your tekin truggy, even geared to 40mph, will probably run above 130-140°F, and, for me, a motor which run above 100-110 °F isnt in its max efficient range.
As the 1520 handle theoritically 2000Watts, I think it will run at 90-100°F max, thats why I take this one instead the truggy or other lighter motor.
Here in Europe there have been many fried rx8 ESC too, and it appears that the mmv3 is the way to go. Its another reason to stay in Castle.
Third reason, castle motor cans are totally closed, and wires already solder internally so its really ready to run (I am not good at solding wires !!!!).

[itbvolks]

I'd agree that higher temps are not efficient. It brings the wire resistance up and hurts the magnets performance so a loss for sure.

The nice thing about motors is they pull the power they need so overall output isn't that big a concern too me personally. Most of these motors are overkill for our apps regardless. BUT, like you mentioned, if they are running hot it's not an ideal setup.

If we're looking at efficiency I'd continue to look at the entire package. I'd eliminate the motor connectors (deans/bullets/everything). I don't care what they say, with the current levels these systems are capable of pulling (160A in cases), they're not efficient. Wire length/guage should be checked, etc (I'm direct wired on the motor).

If I can stay in the 130-140 range, I'd be ok with that at this point. Obviously if I could roll at 100* it would be better for sure. With the only slight decrease in kv, one shouldn't even feel the top end difference (1850rpm @ 18.5v).

IDK, I guess I'll have to see how that 1520 works for you. My guess is, it'll be better on shorter course slower tracks where there is a lot of part throttle (prolly be better with high traction surfaces too). Longer, tracks with fair WOT time, the increased efficiency will probably be curtailed some due to the overall greater power it "should" consume.

It's only ~75gr heavier so coupled with a RX8, it's tolerable for sure mass wise.

Alright, it's growing on me some more

[nuz69]

I would rather have bought a castle 1520 1.5Y 1300kV if it existed for efficiency but castle seems to keep going with high kV motor for their "High speed powerfull" reputation ^^
For me 1500Watts is perfect for a buggy so a truggy need 1800-2000Watts. And the tekin has 1400Watts
I didn't take a neu because a neu hasn't big bearings, has hard wires (very easy to break or to short), and open cases which is very awfull for off road application !
So I have this small monster ^^ let's see how it works just have to wait my RC monster conversion kit, some holes in chassis to adjust battery tray and GOGOGO :D

[itbvolks]

Keep me/us post on how it works out. I'm interested to hear how it works for you.

It's certainly a powerhouse. We'll see if it's driveable. Bruce certainly has his RC8e running strong with it.

I totally agree with the 1300kv version. Run it on 6s and you'd be set.