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hi!
nice conversion.
I have seasoning in BAJA.
Can you buy Motor mount and pinion holder?
Is there Motor mount and pinion holder usable elsewhere?
thank you^^

Quote:

Originally Posted by gyn77 (Post 245773)

to Byte:
I don't know which model of eagle tree I have used, because it is of my friend. I will ask him.

to Othello:
The sentilon works great (and is very cheap), you can see at about the third minute of the video2 the baja on 2 back road while starting at full gas.
Yes, max motor temperature was 58° (celsius) at about 16° of air temperature, sentilon was at a max of 50°.

I attach here the eagle tree log file.

My only doubt is about zippy lipos, they are rated for 20-30c, I got 172 ampere from them, that are about 35c. Do I risk to damage them?

Ok thank you! :yipi:

Quote:

Originally Posted by gyn77 (Post 245773)

it looks like the 172 amps were your burst, and with a 25c continous pack 35c burts are well within limits, Flightpower packs can handle 50c bursts, these bursts will be WOT from a standstill

Awesome build, very clean. I wonder if HPI are watching... (Savage > Savage flux, yada yada...)

@gyn77
Sorry for the late reply. Thank you for sharing your eagletree files. Very interesting especially since you also included a run with 12s1p A123.

Although a 12s1p A123 pack has a higher nominal voltage than your 9s zippy lipo pack, the A123 pack was only able to provide up to 3160 Watt or 100-120A due to its drop in voltage (especially at the beginning of your run where voltage dropped to 1.8V per cell as it obviously must have been relatively cold). With time (as it warmed up due to the load) the pack held its voltage better at high amp peaks - around 2.1V at 120A loads.

You were really pushing your A123 cells. If you want to get about similar performance to your 9s lipo pack you will need a 11s2p A123 pack. It has slightly less energy, wheighs around 400-500gr more but would be able to provide amp burts around 200-240A (up to 5.5KW). Average Voltage would be around 33V (comparable to your 9s lipo pack). But i don't know if the Sentillon would be able to feed as many Amps and if the motor would hold up to those high Amp peaks (efficiency can't be very good at those amp levels).

I think you were also pushing your lipos as they also dropped to 3.1V per cell when they had to provide around 170A. You might want to use a smaller pinion to reduce load on your lipos and motor.

Fantastic work, very inspiring. I feel a project brewing