Mamba x with sensored 2400kv geared at 20/50 only hitting 30mph, need help!

[JS88]

Any advice would help. I have a traxxas fiesta st (basically a slash 4x4 lcg) and it is equipped with a Mamba X and Castle 2400kv sensored motor. It is geared at 20/50 32p and I'm only hitting 30mph at the most. I've ran it with a 4200mah 120c 3s and a 5200mah 60c 4s, what am I doing wrong? I'm looking to hit atleast 50mph like everyone else with the same setup. I did have the slash 4x4 complete slipper in it and changed the spur from 54t to 52t down to 50t at the moment.

[Panther6834]

I have a Losi Baja Rey, with 13T pinion, running on the Mamba X, and a Tekin ROC412 HD 3100kV motor, which I run on 3S. After I first installed this combo, I also expected to hit/break 50moh...however, I was also having "speed problems".

Just curious, but, have you tested your full-throttle 'forward' speed, and compared it to the full-throttle 'reverse' speed? I'm asking, because I'm wondering if you might have accidentally done the same as I did. I accidentally programmed the ESC, as well as the Tx, backwards. I will mention, at this point, that, smoking the ESC programming, I had set the reverse speed to be 50% of the forward speed (you'll understand why I mention this soon enough).

With both the ESC & Tx being 'backwards', pulling the throttle did move the vehicle forward, and 'reverse' did cause the vehicle to go backwards...however, I also discovered that my reverse speed was twice that of my forward speed. That's how I came to realize I had programmed the ESC & Tx 'backwards'.

I'm not saying you've done the same...but, it is a possibly, and one you should check. If I'm right, you should have things corrected in no time. If it's something else...and, in all honesty, I'm hoping my initial assumption is correct...then, hopefully, someone else can help you figure it out quickly.


~ More peace, love, laughter, & kindness would make the world a MUCH better place

[JS88]

I have a Losi Baja Rey, with 13T pinion, running on the Mamba X, and a Tekin ROC412 HD 3100kV motor, which I run on 3S. After I first installed this combo, I also expected to hit/break 50moh...however, I was also having "speed problems".

Just curious, but, have you tested your full-throttle 'forward' speed, and compared it to the full-throttle 'reverse' speed? I'm asking, because I'm wondering if you might have accidentally done the same as I did. I accidentally programmed the ESC, as well as the Tx, backwards. I will mention, at this point, that, smoking the ESC programming, I had set the reverse speed to be 50% of the forward speed (you'll understand why I mention this soon enough).

With both the ESC & Tx being 'backwards', pulling the throttle did move the vehicle forward, and 'reverse' did cause the vehicle to go backwards...however, I also discovered that my reverse speed was twice that of my forward speed. That's how I came to realize I had programmed the ESC & Tx 'backwards'.

I'm not saying you've done the same...but, it is a possibly, and one you should check. If I'm right, you should have things corrected in no time. If it's something else...and, in all honesty, I'm hoping my initial assumption is correct...then, hopefully, someone else can help you figure it out quickly.


~ More peace, love, laughter, & kindness would make the world a MUCH better place

Thats funny that you've mentioned this, for weeks I've been reading forums and doing all kinds of research and playing with my gearing that I had just came across this exact suggestion which is the only thing I've yet to try. After reading that I came back here to find ur same suggestion. Thank you I will try this, crossing my fingers.

[JS88]

Thats funny that you've mentioned this, for weeks I've been reading forums and doing all kinds of research and playing with my gearing that I had just came across this exact suggestion which is the only thing I've yet to try. After reading that I came back here to find ur same suggestion. Thank you I will try this, crossing my fingers.

I forgot to add that my reverse is set to 60% and throttle to 100% and I am certain that my forward is faster than reverse. Does this eliminate ur suggestion? Or do I have to adjust reverse to 100% and try it then to see if reverse is faster with both at 100%?

[Panther6834]

I forgot to add that my reverse is set to 60% and throttle to 100% and I am certain that my forward is faster than reverse. Does this eliminate ur suggestion? Or do I have to adjust reverse to 100% and try it then to see if reverse is faster with both at 100%?

That depends on whether the programming is in the ESC, or the Tx. If you limited the reverse speed through the Tx, know that you should never do that. Yes, transmitters do provide this 'option', but it should ONLY be used if programming such within the ESC is not a possibility.

When I said I have reverse set to 50% of throttle, that's entirely in the ESC's programming...on the Tx, throttle & reverse are both set to 100%. You also never set throttle/breaking curves from within the Tx (again, unless such options aren't available in the ESC's programming). Typically, the only "limiting" I do within the Tx is servo endpoints. Put another way, whenever the ESC & Tx both offer setting/programming options, always do then within the ESC.

Hopefully, this can help you determine whether the "problem" you're experiencing is nothing more than programming 'error', whether your electronics are "problematic", or whether something entirely different it's going on. I have 3 Mamba X ESCs, in 3 vehicles. Where I "goofed up" was in forgetting that the transmission in the Baja Rey is, essentially, 'reversed'. Where certain motor-control settings are concerned I programmed it almost the same as the other two, which led to me seeing motor direction 'Reversed' on the Tx, which led to the situation mentioned in my first post.

As the Slash transmission is similar to that in the Baja Rey...both of which are 'reversed', when compared to my Capra & SCX10 transmissions...that is why I thought you "problem" might be similar to what I initially experienced. Again, I could be wrong...but, one never knows, at least until you truly check into it.


~ More peace, love, laughter, & kindness would make the world a MUCH better place

[JS88]

Yes all these settings are referring to ESC and not Tx, I agree on adjusting ESC over Tx as first.

[Steve g]

Was that feista originally brushed? If so, it would have a lower gear ratio in the diffs, causing a noticeable drop in top speed compared to the vxl diff. Now you could change both diffs to the vxls, but honestly for the cost, I'd recommend first trying to re gear the spur and pinion to make up the difference.

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[NitroBugg]

To help troubleshoot, you could set it with NO reverse and see if it still goes forward. If not, then you can swap settings in the ESC.

At least to me, what Panther stated is good info. Not sure about the Brushed vs Brushless gears.

[Panther6834]

To help troubleshoot, you could set it with NO reverse and see if it still goes forward. If not, then you can swap settings in the ESC.

At least to me, what Panther stated is good info. Not sure about the Brushed vs Brushless gears.

I'd have to be in agreement...especially considering he's already swapped the spur & pinion gears for faster gearing. As for programming the ESC with no reverse, that's another great idea...and one, I admit, I never thought of. It's "interesting" how, sometimes, the 'simplest' (possible) solution eludes me...LOL


~ More peace, love, laughter, & kindness would make the world a MUCH better place

[Squeegie]

Was that feista originally brushed? If so, it would have a lower gear ratio in the diffs, causing a noticeable drop in top speed compared to the vxl diff. Now you could change both diffs to the vxls, but honestly for the cost, I'd recommend first trying to re gear the spur and pinion to make up the difference.

Sent from my SM-G970U using Tapatalk

^This.

With 2200 and 3S with 20/50, mine was running 42 mph.

[JS88]

So I've double checked everything, throttle on Tx is on normal and not reversed. Reverse works as is should even when I drop reverse speed its slow on reverse only. And yes this was originally brushed but even traxxas site states that it is brushless ready and to just swap to a slash 4x4 complete slipper clutch which has already been done. STILL REALLY SLOW. I've seen many exact models converting to brushless and never seen anyone change out diffs.

[danimal82477]

I need help with e revo brushless 1/10 scale v1. The thing rips in reverse but does not seem to get full speed in forward. I just redid the diffs, so they are good. What am I missing?

[Panther6834]

So I've double checked everything, throttle on Tx is on normal and not reversed. Reverse works as is should even when I drop reverse speed its slow on reverse only. And yes this was originally brushed but even traxxas site states that it is brushless ready and to just swap to a slash 4x4 complete slipper clutch which has already been done. STILL REALLY SLOW. I've seen many exact models converting to brushless and never seen anyone change out diffs.

Honestly, then...I'm at a loss. Hopefully, someone else will have a solution for you.


~ More peace, love, laughter, & kindness would make the world a MUCH better place

[JS88]

Just got done playing with motor rotation and/or reversing Tx throttle. All is right as is as far as wiring and rotation. 20/50 gearing hitting 30mph on 3s..

[JS88]

I need help with e revo brushless 1/10 scale v1. The thing rips in reverse but does not seem to get full speed in forward. I just redid the diffs, so they are good. What am I missing?

What esc/motor? Make sure your Tx throttle isn't reversed and if motor rotation is opposite then switch out + and - leads to ESC to correct it. After, recalibrate Tx.

[Squeegie]

I need help with e revo brushless 1/10 scale v1. The thing rips in reverse but does not seem to get full speed in forward. I just redid the diffs, so they are good. What am I missing?

Try switching 2 of your wires from the motor to the ESC, then reverse the throttle directions on your Tx.

Good luck!

[zedorda]

Did you calibrate the throttle end points when you did the swap?

[JS88]

Did you calibrate the throttle end points when you did the swap?

Yes I've checked and throttle EP is at 100%. Using the flysky gt5.

[Panther6834]

What esc/motor? Make sure your Tx throttle isn't reversed and if motor rotation is opposite then switch out + and - leads to ESC to correct it. After, recalibrate Tx.

Try switching 2 of your wires from the motor to the ESC, then reverse the throttle directions on your Tx.

Good luck!

That doesn't work when using a sensored motor, which he is.


~ More peace, love, laughter, & kindness would make the world a MUCH better place

[Squeegie]

Since you are running your system sensored, make sure your wires from motor to ESC are correct... A to A, B to B, and C to C.

Other than that, I am lost on your problem as well.

I looked at the parts list on the Rally and the diff gears are the same as the Ultimate/Platinum Edition Slashes. Was your rig new to you or used? Maybe the original owner unknowingly swapped the diffs (or diff gears) out to the brushed Slash ones?

Good luck and keep us posted.

[JS88]

Since you are running your system sensored, make sure your wires from motor to ESC are correct... A to A, B to B, and C to C.

Other than that, I am lost on your problem as well.

I looked at the parts list on the Rally and the diff gears are the same as the Ultimate/Platinum Edition Slashes. Was your rig new to you or used? Maybe the original owner unknowingly swapped the diffs (or diff gears) out to the brushed Slash ones?

Good luck and keep us posted.

It was bought used, it had the mamba x and castle sensored 5700kv geared at 23/83 48pitch and was quick. Then I did alot of reading that the 5700kv was more for 2wd and would heat up faster. So I went with the 2400kv and switched to 32 pitch gearing, wish I went for the 2650kv or higher. I've heard alot of good things about this 2400kv but i just gotta figure this out. And yes all wiring is correct, double checked.

[Steve g]

What size tires are on it now?
And that question about the motor rotation, where does he say hes running sensored? Just says erevo v1. Was from a different poster, not the op.
Anyway back to the op here. You went from 23/83 with a 5700kv, to 20/50 with 2400kv. While your gearing is higher, its no where near the change in ratio that the change in motor kv is. You'd have the same top speed on the same battery with the current gearing with about a 4000kv motor as you had with your original set up. I ask about tire size to compare to squeegies speed.

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[JS88]

What size tires are on it now?
And that question about the motor rotation, where does he say hes running sensored? Just says erevo v1. Was from a different poster, not the op.
Anyway back to the op here. You went from 23/83 with a 5700kv, to 20/50 with 2400kv. While your gearing is higher, its no where near the change in ratio that the change in motor kv is. You'd have the same top speed on the same battery with the current gearing with about a 4000kv motor as you had with your original set up. I ask about tire size to compare to squeegies speed.

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Current tires are some knock off short course tires about the same size as stock slash, have even tried it with the stock rally tires. I don't have any of the beefy bigger tires on. And yes I've seen thi setup with 18-19/54 doing 45+mph with 3s.. n to mention again I also have a 4s 5200mah 60c lipo that doesn't prove much, not even cracking 45+ with it at current 20/50 gearing.

[Panther6834]

And that question about the motor rotation, where does he say hes running sensored?

Op said "sensored" in his initial post.


~ More peace, love, laughter, & kindness would make the world a MUCH better place

[JS88]

I need help with e revo brushless 1/10 scale v1. The thing rips in reverse but does not seem to get full speed in forward. I just redid the diffs, so they are good. What am I missing?

@Panther6834

He was referring to this, it was asked somewhere in the middle by another person other than myself (op).

[Panther6834]

@Panther6834

He was referring to this, it was asked somewhere in the middle by another person other than myself (op).

Ah. Must have missed that one. Even the most observant didn't catch everything...and, I'm by far (VERY far), not even close to the most observant.


~ More peace, love, laughter, & kindness would make the world a MUCH better place

[Squeegie]

It was bought used, it had the mamba x and castle sensored 5700kv geared at 23/83 48pitch and was quick. Then I did alot of reading that the 5700kv was more for 2wd and would heat up faster. So I went with the 2400kv and switched to 32 pitch gearing, wish I went for the 2650kv or higher. I've heard alot of good things about this 2400kv but i just gotta figure this out. And yes all wiring is correct, double checked.

Still makes me wonder if the original owner unknowingly changed the diffs to the ones used in the brushless Slash (6778 vs 5379X or R)...

[JS88]

Still makes me wonder if the original owner unknowingly changed the diffs to the ones used in the brushless Slash (6778 vs 5379X or R)...

I've reached out and he confirmed all was stock no changes in the diffs. But thats just me taking his word for it.

[Squeegie]

Hmmm... training mode?

[JS88]

Hmmm... training mode?

I haven't seen a training mode in the Mamba X settings.

[RCWilly]

Hmmm... training mode?

I don't think Castle has training mode. Adjustments are made using Castle Link... does tightening the slipper work?

[JS88]

I don't think Castle has training mode. Adjustments are made using Castle Link... does tightening the slipper work?

I will try fully tightening the slipper first thing tomorrow as I haven't done that and then run it with a set of hoons tires that I have. I did notice that when i hold the car up and punching full throttle that it feels powerful and fast, it balloons my short course tires. But on the pave it feels less powerful. I've never noticed any slipping but then again I am not as experienced with these faster cars. I've only mainly messed with crawlers.

[dgechrgr469]

You're not going to be able to check the slipper unless you test it in under a load. Most recommend tightening it fully then backing out 1/4 to 1/2 of a turn as a good starting point.

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[JS88]

You're not going to be able to check the slipper unless you test it in under a load. Most recommend tightening it fully then backing out 1/4 to 1/2 of a turn as a good starting point.

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I'm not sure if this info helps but earlier today I've held onto the back of car while pushing full throttle and all tires do spin leaving little skid marks on the pave, but never really heard it slipping/grinding. But again, I haven't gone in to fully tightening it because I didn't think it would cause my lack of speed so yes I will try it. When I held it and throttle, it spun all wheels enough to leave tire marks but i didn't it spin as fast as it would while all 4 tires were off the ground.

[Steve g]

Maybe just start over. Redo the binding of the receiver and the calibration of the esc, and the esc settings.
And what are you using to program the esc? Sometimes the Bluetooth module says it changes esc settings, but it actually doesn't go through.
Also find a rc speed calculator online, put in your old set up, see if its accurate to your old speed, then put in your new setup, and see if its close to what it says it should be, or how far off it is.
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[Squeegie]

Are you sure the gears are 20/50? Do an actual physical check of the gears. Look for the tooth count stamped on the gear and/or count the teeth.

Any pics if your rig?

[JS88]

Maybe just start over. Redo the binding of the receiver and the calibration of the esc, and the esc settings.
And what are you using to program the esc? Sometimes the Bluetooth module says it changes esc settings, but it actually doesn't go through.
Also find a rc speed calculator online, put in your old set up, see if its accurate to your old speed, then put in your new setup, and see if its close to what it says it should be, or how far off it is.
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I am using the castle link (wired) and I've been going back and forth into it adjusting and testing. All settings are always what I last set it at when I go back in to check. I sold the 5700kv because I already had the 2400kv in hand and was to stoked to test first lol. Wish I waited..

[JS88]

Are you sure the gears are 20/50? Do an actual physical check of the gears. Look for the tooth count stamped on the gear and/or count the teeth.

Any pics if your rig?

I am sure about gearing because when I bought the 2400kv I also bought the slash complete slipper clutch (54t 32p spur) and then I got pinions, I didn't have any 5mm pinions so all were purchased new as well as the 52t and 50t spur. I went from 18/54 to 19/52 to 20/50.. a few other gearing in-between the switches. About to try tightening the slipper. I can show pics while I open the gearing to tighten, what I best way to upload pic?

[Panther6834]

I can show pics while I open the gearing to tighten, what I best way to upload pic?

I won't say it's the "best" way (although, many might say it is, possibly including me)...but, uploading via the TapaTalk app (Android & iOS, as well as via the website) is, most definitely, the "easiest" way. When uploading photos via a forum's own website, you must first upload to a 'hosting site' (such as Photobucket)...but, with TapaTalk, they are not only a way to access multiple forums, but they also provide their own photo hosting service.


~ More peace, love, laughter, & kindness would make the world a MUCH better place

[RCWilly]

The image posting thing here can be a bit finicky at first, but once you do it once or twice, it gets easier. If you are using a phone to post the image, many people use the Tapatalk app (I am not completely sure how that works, but many people seem to like it). If you are using a computer or laptop to post the image, a regular image hosting site is fine. I use Imgur to post images. To do that, first, create an account on Imgur and log in (it's free). The on the top right corner, click on your username and click on images:



After that, just drag the image in, and it should automatically upload.

Next, click on the uploaded image, and it should show a screen like this:



Copy the BBCode, and you can paste it here (without using the insert image).

Hope this helps!