Slash 4x4 + Mamba Max Pro SCT 2400 not that fast?

[USMC_fallguy]

Ive ran several 4x4's and they're plenty fast, with the stock motor. Just got what I described in the title, and use a 3s 40c battery, and its going about 30? Got a gps to put on it to make sure. My E revo 1/10 is about twice as fast, didnt think this would be the case.

Using a center diff with 19/50. Top end isnt really that big of a deal, as I race short course concrete, but I dont understand why its not very fast. I havent messed with the settings with castle link, perhaps it comes stock limited for some reason?

[zanek]

That is because the motor is a lower KV. The 2400 is the number of KV. The stock motor is 3500 (KV= RPM per volt). But the lower KV means more torque, so you could experiment with gearing up. Though it seems like on 3s lipo it would go faster than 30 mph. Where are you mounting the GPS on the car? I have heard of GPSs giving low readings because the strong magnets on the motor interferes with it.

[thedreadedend]

That motor and battery combo should be pushing mid 50's-low 60's. I have the same combo geared 17/54 and its ape on 3s and higher!

[El Sob]

I have the same combo on 4s and geared 22/50, its good for about 70mph!

[kansas-slash2009]

I'm geard 19/54 with slipper and it fire on wheels expecialy with paddles its like a rocket powerd by 3s, like said be fore its lower kv motor it won't spin as fast but yet run cooler and have heaps more torqe soya gota gear up for the speed if u want it,
I wana see a pulling contest with the different castle motors and realy see what they can do ibet they excell!!

[crusey]

Data is out there comparing all of the Castle motor options what specifically do you want to know ?

Theoretical speed for the 2400 with stock sized tires

2s Lipo
Pin 54 52 50
15 22 23 24
16 24 25 26
17 25 26 27
18 27 28 29
19 28 29 30
20 30 31 32
21 31 32 34
22 33 34 35
23 34 35 37
24 35 37 38
25 37 38 40

3s Lipo
Pin 54 52 50
15 33 35 36
16 35 37 38
17 38 39 41
18 40 41 43
19 42 44 46
20 44 46 48
21 47 48 50
22 49 51 53
23 51 53 55
24 53 55 57
25 55 58 60

4s Lipo
Pin 54 52 50
15 44 46 48
16 47 49 51
17 50 52 54
18 53 55 57
19 56 58 61
20 59 61 64
21 62 64 67
22 65 68 70
23 68 71 73
24 71 74 77
25 74 77 80

Cheers

[USMC_fallguy]

I didn't actually put the gps on it, but I've got one to try. I was guesstimating the speed. My 1/16 slash clocked 45 and it's much faster. I'll try to get some pics and maybe a video and see if that helps figure out what the deal is. Thanks for the replies.

[crusey]

You should be hitting 50 mph with that gearing

Centre diff is probably not suitable for longterm bashing on 3s

Do you have a programmable radio ?

Have you set the throttle travel limit at 100% and calibrated the ESC ?


Grab the castelink and play with the ESC settings, stock settings are not ideal

Take out the timing and bump up the start power

Cheers

[CoreyM]

I just installed mine and it's a dog. Slow. I'm at 18/54 gearing which according to cruseys calculations I should be going 40 cause I'm using a venom 3s 11.1v 5000mah. I dont have gps but I can tell I'm not going 40. I'm going to look into adjustments with the castle link but the way it feels now I don't know if I'm going to get the speed back to where I want it without a 4s. Kinda disappointed so far. I was looking forward to making an upgrade and feel like I might have downgraded. I'm not interested in changing the spur gear cause I just put a robinson racing 54t steel gear in it that was $35. Hopefully I'll be able to do something with the castle link or maybe iv done something wrong myself. If not I guess I just wasted $200 and will be putting the stock setup back in. I'll keep you posted if anything changes and if anyone has any advice for me (us) please keep posting.

Question: So wait a minute, the motor in this combo has a lower Kv than the stock motor, how can it be faster or better?

Answer: Kv doesn't equal power -- these motors are almost 100% more powerful than most stock brushless setups. Ours are four pole motors, with higher quality components designed for improved torque. So go ahead, gear it higher than the stock motor and you'll really feel the difference -- even with the same cell count!????????

[crusey]

If you are not hitting the speeds listed in the spreadsheet I posted something is wrong with your setup

I have confirmed via eagletree gps the following when running 3s lipos

18/52 with Proline Streetfighters (4.5" diam) - 50 mph
21/52 same setup - 53 mph

ESC Settings
0 Timing
High Start Power
Punch Disabled


Cheers

[CoreyM]

If you are not hitting the speeds listed in the spreadsheet I posted something is wrong with your setup

I have confirmed via eagletree gps the following when running 3s lipos

18/52 with Proline Streetfighters (4.5" diam) - 50 mph
21/52 same setup - 53 mph

ESC Settings
0 Timing
High Start Power
Punch Disabled


Cheers

So why on the spreadsheet above does it say for 3s 18/52 should be 41 and you say 50mph?
And 21/52 lists 48mph and you say 53mph?
Sorry just confused.
Thnx

[crusey]

Speeds listed are theoretical based on the scriptasylum website calculator

Calculator assumes the following

4.3' diameter tires (any ballooning will add speed)
3.7v / cell voltage delivered from the battery
Actual loaded motor kv


If any of the above vary then the readings will change

2s speeds were
18/52 - 32 mph
21/52 - 37 mph

4s speeds were
18/52 - 60 mph
21/52 - 67 mph


I have also tested a different motor with similar specs (Tenshock 6 pole x802 2400kv), geared 21/52
2s - 37 mph
3s - 55 mph
4s - 72 mph

The Tenshock SC401 (4600kv, loaded kv closer to 4000) recorded the following speeds, geared 17/52
2s - 44 mph
3s - 62 mph


Cheers

[akesj1]

I'd probably suggest you try slipper rather than c-diff, we do alot of parking lot running/racing & on my MMM/2650 I was not happy with C-diff, it would weight transfer to rear and allow the front tires to spin thus not putting power to rears with traction, switched up to centre diff and it was a Rocket again

[kansas-slash2009]

No go with center diff ull get the snappy ness with the sliipper diff isn't accurate with all that power just with my venom 30c 5000 3s it pretty snappy the aussie is right about his charts and u have to change ur esc setting u need the link I'm running 19/54 and its hard to control and flat hauls across my sand pasture with paddles u just got play with the esc settings

[CoreyM]

So if I'm running a 54 steel spur what's the most amount of teeth I should use on the pinion before I should worry about heat issues
Thnx crusey

[crusey]

19/54 for bashing on 3s is about as high as I would push it

Cheers

[USMC_fallguy]

I ordered the center diff, before I knew that you couldnt use the center diff and slipper at the same time. Which you can do with my E Revo, and 1/16 Slash. Bought it so I thought Id try it. It was slow with it too. The motor/esc are brand new.

So I changed the ESC settings in castle link like suggested. Still slow. Here is a pic of the software, not sure what it is supposed to be? (big pic so you can read it)


I can take a pic of every page to try and figure this out. Its driving me crazy. Its wayyyy slower than my other two RC's. Some pics of the Slash itself, with my crappy cell phone camera;




edit; I am also using a Spektrum DX3e if that makes any difference.

[Luciden]

A couple of things to check:
1. See how fast it goes in reverse. The polarity is backwards on my 3800 and when I first installed it the truck went faster in reverse than forward. If this is the case just swap the +/- to the motor.
2. You may have burned up the plastic bearing adapter on the center diff or your center diff may be damaged from running it on 3S. Swap for a slipper and a metal adapter (thanks to I think it was Crusey for helping me with that issue)
3. You may have other misc binding, frozen bearings, etc...

[USMC_fallguy]

Got it figured out. When I first installed the esc/motor combo, forward was reversed. So I just reversed that on my controller. Well, when I was out playing with it trying to figure out what was wrong, I went in reverse for a good ways. It was wayyy faster than forward. Apparently you can reverse the way to motor runs by swapping wires. Since they are color coded.. I didnt think that would be the case.

So swapped two wires, change my controller back to normal, and now it clocked 44.6 with 19/50 setup on my GPS. Much faster!

[Teknic]

You can put your wires back and go into the CastleLink which it appears you have and change the motor direction from normal to reverse and it will also fix your issue. If of course you're OCD like me and don't like having wires mismatched

[USMC_fallguy]

I will do that.. because I dont like the colors not matching either. Thanks for the tip. I need to go back in there anyways because I reset to default when trying to figure out the problem.

[damselfly]

You can put your wires back and go into the CastleLink which it appears you have and change the motor direction from normal to reverse and it will also fix your issue. If of course you're OCD like me and don't like having wires mismatched

I suffer with rc OCD too, I just can't fight it. lol

[bduncan]

whatever. slash will maybe go 60 with mamba monster and 2200kv

[crusey]

Certainly dont need a 1515 2200kv to go 60, no idea why you keep suggesting it

The 1415 2400kv does it with ease


Cheers

[El Sob]

USMC, I'm happy you figured out your problem! In my Ultimate I am geared 19/54 and it is pretty quick. Doesn't get hot and is a torque monster. I am running the same tires as you have in your pics. On 4s it out of control! My standard Slash 4x4 is geared 22/50. On 4s it is a beast! I have the suspension set low and the tires tapped and a lot of other things done to it. It handles high speed like a champion! You are going to love this motor combo! Oh and by the way, thank you for your service!

[thedreadedend]

The 2200 certainly wouldn't be my first choice motor either. Maybe a fun build if you got the parts sitting around but the 2400 wont kill the truck with wait from the motor and batteries needed to push it. I bet I would snap the chassis, bend motor plates, you'll be fighting for good shock action ..... your truck is getting killed with weight before you even flip the switch!

[illest1989]

Man, i just upgraded to the mmp 2400 combo on 3s in my slash and was very unhappy with its power! i tried everything( i thought) hooked up the castle link and reversed the wires so that it was color coded and running the right way, set the punch to 0%, left the timing alone. Then i saw your post about calibrating, i gave that a shot, but it would not register brake(when the red light comes on)So then i noticed that my radio light was blinking green, Just earlier i binded my new emaxx receiver to the radio and i guess i didn't exit out of the menu. so i did that and recalibrated the esc WOW!!!!!! BINGO!!! MAN THIS THING IS CRAZY POWERFUL!!! i can say its up there with the emaxx mmm 2200kv on 6's! Fully satisfied with it's performance now. Thanks u crusey, and again Traxxas community for all the help