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Have tech questions? Will answer.

Start by following the instructions. Castle esc and Futaba the esc channel needs to be reversed.

Look at your LED on the esc. Yellow is neutral/ stopped, Red should be reverse direction and green should be forward. If not , reverse channel 2


Hang up and Drive
 
How much torque do you get from a motor?


I did some math and it looks like not much, but I may have missed something?

KT=1/KV. So a 2850KV has .0035 Nm/A Torque (KT).
Max RPM is 31,635 on an 11.1V (3S) Lipo.

For the sake of argument lets say it pulls 40A.
So the total torque output would be 0.01404 Nm or 0.00143 Kg-m.

Which is pretty dang low.


The it's compounded by the transmission, transfer case and axles, but still even at 100:1 it's still super low.


What did I miss?
 
How much torque do you get from a motor?


I did some math and it looks like not much, but I may have missed something?

KT=1/KV. So a 2850KV has .0035 Nm/A Torque (KT).
Max RPM is 31,635 on an 11.1V (3S) Lipo.

For the sake of argument lets say it pulls 40A.
So the total torque output would be 0.01404 Nm or 0.00143 Kg-m.

Which is pretty dang low.


The it's compounded by the transmission, transfer case and axles, but still even at 100:1 it's still super low.


What did I miss?
I don't know what you missed, https://m.facebook.com/groups/1615514595438121/permalink/2461703704152535/

Here is a some motors from a dyno showing their torque.

The torque is linear, and not constant.

__________________________
Handy gearing spreadsheet
 
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Put a V2 Snubnose 1800kv Revolver in one of my Gelande II’s with a Mamba X. For a reference I set setting as John did in his, low and slow programming video. Course it was a sensored BL in the video, so not sure if I’m even on the right track using those same settings. Anyway, I’m having cogging issues on start up. Not sure if it’s just my poor trigger finger, or if it is simply programming on the Mamba X that can resolve it. Thought maybe it was due to how heavy the RC4WD rigs are, so I purchased the 540 size 1800kv Revolver. But same issue. Thoughts??
If it helps, here’s a quick rundown of my settings.

BEC voltage - 7.4v (Protek 370TBL)
Start Power - High
Max Power - 100%
Punch Control - 30%
Throttle Curve - Basically pulled horizontal 60, down to the 3rd vertical line. Kinda like shown in attached pic.
bd016fed5b0b2ab1f6d520a191ce2c58.jpg



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What’s your battery voltage and gearing? If you’ve watched Holmes videos you’ve probably seen the volt up gear down saying.


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What’s your battery voltage and gearing? If you’ve watched Holmes videos you’ve probably seen the volt up gear down saying.


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Ah yes, great thought. Using 3s on a 12T pinion. Stock pinion was 14T.


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Have you tried starting it up with the throttle trim to rule out your trigger finger?


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I have not. But may need to clarify a bit. There’s no cogging when starting on a flat surface with a steady smooth trigger pull. It’s when attempting to ascend an object that it starts cogging. Course not every time. Sometimes it performs perfectly. I’ve never used an external BEC with a Mamba X/Puller Pro set up. So assumed I wouldn’t need with an outrunner as well. Is it possible an external BEC is what I should be looking to add?


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I have not. But may need to clarify a bit. There’s no cogging when starting on a flat surface with a steady smooth trigger pull. It’s when attempting to ascend an object that it starts cogging. Course not every time. Sometimes it performs perfectly. I’ve never used an external BEC with a Mamba X/Puller Pro set up. So assumed I wouldn’t need with an outrunner as well. Is it possible an external BEC is what I should be looking to add?


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It was my understanding that a BEC is for servos/accessories? I couldn’t imagine that causing issues with the motor starting up.


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I have an extremely lardy (heavy with many metal upgrades) Bomber running a Mamba X/Revolver 1800kv v1 and have no cogging at all using the settings from am older video that JRH had...
 
I have an extremely lardy (heavy with many metal upgrades) Bomber running a Mamba X/Revolver 1800kv v1 and have no cogging at all using the settings from am older video that JRH had...


Sweet!! Thanks man good to know. I can take the MX/Revolver set out of the equation. Now to figure out the next thing to start looking at. Any thoughts?


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I think your curve is wrong. Durock refers to the old TRX4 video setup. I run that same curve with both PullerPro’s and revolvers. Silky smooth low end on all. First off, calibration Tx/Rx, to the esc. Sec d make sure you have the last firmware from Castle.
Bump up the curve a bit in the beginning.


Hang up and Drive
 
Sweet!! Thanks man good to know. I can take the MX/Revolver set out of the equation. Now to figure out the next thing to start looking at. Any thoughts?


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That's not how it works...

but sounds like your having sync issues, that's why sensor less motors cog. can happen when the motors turns slower then expected due to increased resistance, like climbing. I would suggest dropping the pinion more, this will decrease the resistance.

also Holmes has often suggested playing with the torque limit in the esc programming. I have no idea why it would help but worth a shot.
 
I have an extremely lardy (heavy with many metal upgrades) Bomber running a Mamba X/Revolver 1800kv v1 and have no cogging at all using the settings from am older video that JRH had...


I set up my mamba x verbatim to that earlier video also. Have no issues as well with PP2700 and Revolver 2500.
 
Make sure your timing is set to 0° for a revolver motor. I have noticed that you get smother starts with higher drag brake setting.
 
Anyone having issues with castle's b link not working on android since the October update? It won't show any esc on the link controller page, yet in my phones blue tooth I can see the b link. I've emailed them twice, no response.

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Anyone having issues with castle's b link not working on android since the October update? It won't show any esc on the link controller page, yet in my phones blue tooth I can see the b link. I've emailed them twice, no response.

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I can only reply so you know some one heard you, unfortunately I do not have a b-link. I would delete the app data, then uninstall the app and reinstall it.
 
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