Ok, so you're saying that a 22/45/3 is a batter choice with 12s than a 22/45/2 with 10s?
EDIT: I would like to have softer start to save my transmission and differentials.

It really depends what gearing options you have. Crunch some numbers using BrianGs speed calculator. If you can reasonably gear a motor with 40000rpm. Go for it, but it might run hotter then a motor revving at 30000-35000rpm. If you want more runtime and lower temps go with the higher wind version. Either on 10s or 12s A123.

Wheight depends on how much does a savage roller wheigh? Wheight of your electrical components is easily calculated. Wheight of your desired tires really can make a difference in wheight. I never converted a savage, so i can't tell you.

I've been using his calculator alot. I'll use the /3 wind, plus in some numbers, and see what it spits out. :yes:

Here is what I got:


Differential Ratio: 3.3076923076923075
Transmission Ratio: 1.5833333333333333
Other Ratio: 0.967741935483871
Spur Tooth Count: 49
Pinion Tooth Count: 14
Total Voltage: 39.6
Motor KV: 1000
Tire Diameter (inches): 7
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0
Spur/Pinion Ratio: 3.5 : 1
Total Ratio: 17.73883 : 1
Tire Circumference (inches): 21.99 inches (558.58 mm)
Total Motor Speed: 39600 RPM
Vehicle Speed: 46.49 mph (74.68 km/h)
Effective Speed Rate: 1.17 mph/V (1.89 kmh/V)
Estimated Adjusted Speed: 44 mph (70 km/h) - 6% loss
Effective KV Value: 1000
Motor Torque: Amperage not specified...
Final Torque: Amperage not specified...
Final Power: Amperage not specified...

You have to reduce total voltage to 32-36v (with 12s under load at full speed). A heavy truck sucks 800-1500 Watts at those speed levels (above 40mph) depending on the surface you run it. Meaning you will need up to 45A. At this amp level voltage of A123 cells drops down to 2.8v per cell.

So 33v will give you a more realistic speed and rpm under load.

Alright. This seems like my setup, just have to sell a few things before i start buying. :party:

Good luck with it. Will be interesting to follow up and see how the components behave in a heavier truck.

I have the Mega ACn22/30/2 in my truggy and it runs nice and cool. I have a 14T pinion and 49T spur. The diffs are from the buggy so they are 3.3 ratio. I tried a Feigao 7XL with 4S and it ran hot. You will be amazed on how a well geared Mega will run.

Hopefully it will all work out. I am working on pricing right now. :wink:

@lutach
Hmm ...interesting. Such a light and small motor in a truggy and no temp probs. This really sounds amazing. I never would have considered such a light motor in a truggy. I thought a Neu 1512 is already some kind of a light wheight in a truggy. it performed very well in my truggy but was more on the hot side when compared to the Neu 1515. Those Mega 22/50 seem to be tempting for bigger projects.

I was impressed as well. I was going to put it in a buggy, but I just had to try it in my truggy. Too bad my Schulze 18.97 didn't last long enough. I did put my little old 18.61K and this little guy is having fun. Let's hope it'll last longer then his big brother.

Wow! I am surprised that the 18.61 can handle the 70a motor pull.

The burst rating of the controller is 81A and I tested today and it only pulled 61A with me holding it down a bit :lol: (Don't try this at home kids). It left some nice marks on my wooden floor. BTW max amps it pulled with the 18.97 was 75A.

That's interesting.

This is just my opinion but I personally would get rid of the tranny alltoghther. Its gonna give you nothing but problems. I would look into a buggy center diff or an outrunner direct drive setup. The direct drive setup would be perfect for a 12s lithium setup since thats what their meant to run at. If you want proof that that tranny isnt strong enough well then this might change your mind- http://youtube.com/watch?v=J_VWhdE4HRk

And to think that this is only 6s. 12s is gonna be one helluva strain on the tranny.