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Mamba Max Tuning Guide (continued)
Higher advance makes the motor run hotter, and the higher the Kv of the motor, the hotter it will get! Too high of an advance setting will give the same results as too much advance on a brushed motor – you will actually LOSE power and speed while the motor cooks itself! If you want to go faster – JUST GEAR UP!
The drag brake setting works a little differently than most brushed motor drivers are used to. The drag brake setting response is engaged as a brake when the trigger is at the neutral position. If you set a 30% drag brake on the controller, you will have that % of braking power when the trigger is at neutral. Moving the trim towards the brake side on your transmitter will NOT give you more drag brake. If you like to adjust the amount of drag brake “on the fly” during a race, then disable the drag brake setting and use the throttle trim like you’re used to doing with the main brake % turned UP on the ESC. You might also want to raise the left hand portion of the bake response curve on the ESC if you like very aggressive drag brake. If you will be moving the throttle trim around like that, be aware that the ESC needs to see a neutral pulse from the radio to arm, and you may need to move the trim back to zero the next time you plug the ESC back in to run. Also, using the transmitter to adjust drag brake will require you to be in the “Forward/Brake only” mode on the ESC to keep the car from going in reverse at neutral throttle.
 Don’t be embarrassed if the speed and power seem like way too much for you and the vehicle at first! Almost 100% of the top pro drivers and industry leaders that evaluated this system asked us the above question. The good news is – you WILL get used to it! One of the most popular phrases we used with trembling first time Mamba drivers was “If you had a Ferrari, would you have to drive it full throttle through your neighborhood?” It can take a while to adjust to having up to 5 times more power and speed on tap, but here are some tips to mellow things out while you’re learning to tame the Mamba Max:
1) Gearing is the best tool to tame (or get more) speed. Go down to the smallest pinion, and largest spur gear you can fit to your vehicle, and then slowly gear back up to wherever you’d like to be as you get used to the feel.
2) Timing advance makes a small difference in power, but it’s noticeable, so drop it down to the lowest setting
3) Manipulating the cutoff voltage can make a BIG difference, especially in punch and torque. If you’re running a 6 or 7 cell NiMH or NiCad pack, try using the custom 4v cutoff setting instead of no cutoff. This will greatly limit acceleration and speed. If you are using LiPo packs, try a custom cutoff voltage setting about a volt or two under the packs fully charged voltage. For 2 cell Lipo packs, a 7v cutoff voltage works well, and try a 10v or 11v cutoff setting for 3 cell Lipo packs.
Note: When you use an elevated cutoff voltage, the runtimes will be shorter because you aren’t using the whole capacity of the pack.
In internal and beta testing, we were unable to find gearing options that would actually thermal the controller when used within spec:
Max input voltage for ESC: 3s lipo or 12 cell NiMH/NiCah
5700Kv motor max voltage: 3s
7700Kv motor max voltage: 2s
The Kv of a motor is the number of rpm’s it will turn per volt of input. So the 4600Kv motor will turn 4,600 rpm per volt of battery. On a 6 cell pack we can presume good cells are holding around 1v per cell, so 6v x 4600Kv = 27,600 motor rpm.
On the other hand, if we take a 3 cell lipo pack with the 7700Kv motor, that gives us 10.5v x 7700Kv = 80,850 motor rpm which is safe for the ESC, but well over the safe motor rpm limit so it cannot be used either.
So how can you get the most speed? You might think the 7700Kv motor having the highest Kv would automatically allow you to have the fastest setup right? Let’s find out:
7700Kv x 2 cell lipo voltage (max with this motor) = 53,900 motor rpm.
5700Kv x 3 cell lipo voltage (max for the motor and ESC) = 59,800 motor rpm
So the fastest 5700Kv motor setup is actually 6,000 motor rpm faster than the fastest allowable 7700Kv motor setup!
Now if you are racing with 6 cell packs only, then obviously the 7700Kv motor will be the fastest option for you, but we are routinely asked “what is the absolute fastest setup for my car/truck?” The answer in this case, is the 5700Kv motor with a high quality and high output 3 cell lipo pack made for 10th scale cars.
We are working on a speed chart, to show actual measured top speeds with 6 cells, 2s and 3s lipo packs in a variety of vehicles with “normal” or very conservative gearing. We have a confirmed measured speed of 62.4mph with a touring car on 3s lipo and the 5700 motor from one of our beta testers. From our best estimates, very near 60mph should be easily attainable in touring cars, as well as 2wd buggies and stadium trucks with the 5700 motor and 3s lipos.
On 6 cells:
4600 motor ~ 25mph
5700 motor ~ 35mph
6900 motor ~ 40mph
7700 motor ~ 45mph
On 2s lipo:
4600 motor ~ 30mph
5700 motor ~ 40mph
6900 motor ~ 45mph
7700 motor ~ 50mph
On 3s lipo:
4600 motor ~ 45mph
5700 motor ~ 60mph
Look for software updates with more tuning aids to totally dial in your Mamba Max for any driving situation being constantly added to our website, as well as additions to this tuning guide as we gather more user tips and experiences to pass along!
Now go pull the trigger and light em up!
Castle Creations staff
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