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Old 10-01-2008, 06:22 PM   #1
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Questions?? Traxxas Slash and Neu motor question

Hello, i've a Slash and ran it with a Feigao 10L, mamba max ESC and Thunder power 5000mAh, 3s li-po, but last week-end i've toast my Feigao with sand go in the can (my fault !)

Ok yesterday i've order a Neu 1512, 1.5d/s, (3200Kv, 135A max).
I know some guys here will tell me that i'am crazy to put this motor in a slash, but you're right, i'am crazy
So now, my question is for the king of brushless here on this forum.
I want to know if this motor will pull to much amps on my Thunder power lipo (5000 mAh, 11.1 volts), if my run time will be shorter than with my Feigao 10L and if my runing temps will me too high

I'll be geared with Jato 32 pitch, 58T spur and 13 pinion, with badlands tires (4.8" diameter). This setup give me about 43m/h, and with my previous Feigao 10L, i was geared for the same speed with cool temps.

But i'am a crazy guy, and i've don't take any chance, today i've order a Neu 1509, 2.5d/s 2700Kv, just to have a spare motor in case that the 1512 will be too much.
But as i said, i like power, and i like to have a bigger motor for what i need

Thank you !

David
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Old 10-01-2008, 06:25 PM   #2
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good luck fitting a 1512 in it.
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Old 10-01-2008, 06:35 PM   #3
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No problems bro, the Neu 1512 is the same dimension as a Feigao "L" can, 36mm x 60mm, and my Feigao fit nicely in my Slash
I've take the "s", smooth can, not the finned one!
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Old 10-01-2008, 08:45 PM   #4
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too bad, you're right chewiefttc4, the Neu can is 40mm diameter Impossible to fit it. The only way is to cut the stock gearbox or buy the FLM alloy tranny case.

And goodbye to the rear bumper
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Old 10-02-2008, 12:06 AM   #5
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email neu and ask for a replacement of the diameter you need.
im sure steve will take care of you.
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Old 10-02-2008, 09:30 AM   #6
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Quote:
Originally Posted by chewiefttc4 View Post
email neu and ask for a replacement of the diameter you need.
im sure steve will take care of you.
No need, i have order the FLM alloy tranny case from rc monster. This tranny case have just the aluminium plate to bolt the motor, she do not have the plate under the motor, so i will can put my Neu without any problems.

If i want a smaller Neu, i will have to go in the 11xx serie, and it is too small for what i need in my Slash.

And anyways, i will probably buy a crt.5 soon, so my Neu will fit without problems in the little crt.

Thank you!
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Old 10-02-2008, 10:38 PM   #7
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To answer your question with the Neus your output rpm is up 34%, so you need to gear down

With the 1515 13t pinion you need a 77 tooth spur; with a 58T spur you need a 9 or 10T pinion. With the 1509 and a 13t pinion you need a 64 tooth spur; with a 58 tooth spur you need an 11t pinion

The Neu 1515 has about 1/5 of the resistance of the Feigao, the 1509 has bout 1/3. On both Neus the Io will rise by much less than the Feigao motor once it is revved up.

This means the max efficiency of the 10L is approx 50 amps; the 1512/1.5D is about 105 amps & the 1509 is 77 amps

With the shorter gearing the lower resistance of the Neu means they may well l pull higher short term current spikes. The up side is that geared for the similar speed (in theory at least) the Neus deliver more torque per amp and are very efficient so the spike will drop much faster than with the 10L. You will fast acceleration but also longer runtime.

You could use an eagle tree data logger to ensure you are not spiking too high Ė the 150 amp V3 is the one to use. If the money is too much think about this; the pack is worth more and the data logger will let you set the car up so it is very fast and the cells canít get hurt and you can stop being concerned.

Also more important to helping the cells survive is a/ warming them after charging and before use; and b/ not using more than 75% of its capacity. With the logger you can work out how long that is. Cold cells or a highly discharged lipo are far more likely to puff than ones which are hot & have more than 25% charge left in them.

Andrew Gilchrist
www.fastelectrics.com
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Old 10-03-2008, 09:57 AM   #8
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Wow!! thank you Andrew, very appreciated!. But for my gearing, as i said in my first post, i use 32 pitch Jato gear, so this is for this reason that i have to use 13/56 with my 1512, 3200Kv motor. I think that you speak about the stock 48 pitch gear in your reply, right

And another question, how can you warm a li-po pack before to use it
And now problem to use only 75% of the pack, this is always what i do.

And for the eagle tree V3 150Amps, i have order one yesterday, like that i will monitor my system.

Thank you again, this is the kind of reply i like to have

Very appreciated.

David
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