LAVAGIRL - tomiboi MTB | ubox v1 | 12s8p p42a | Luna 350s | Reacher 6485s

Yes, if Maximum Duty Cycle is above 90%, that’s good.

I don’t see Maximum Duty Cycle anywhere in the freesk8 tool…

Edit: found it in normal VESC tool, set at 95%

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Yeah that’s good. Next guess would be ABS overcurrent or a phase short.

Check all your physical connections for loose connectors/shitty joints (particularly factory bullet connections)

Phase shorts can happen internally within the motor as well. @b264 can link you to a thread on how to hand test the motor for shorts. If the motor is shorted, it can be for a number of reasons, most commonly using mounting screws that are too long.

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@haven damn bruh that is fucking gnarly. Glad you are not injured in a very serious way.

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Damn! I would definitely replace the helmet after a spill like that at that speed. Sounds like you can get a discount on a new one though from TSG if yours saved your ass though

Sucks about all the broken bits on the board :weary:

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I second this, I just had it happen recently. All of a sudden, too. Thankfully, I was not going fast.

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What is/causes ABS overcurrent?

As far as i’m aware its a current spike beyond your abs max current setting. It can be caused by a number of things (like shitty/intermittent connections), but for me I’ve only ever noticed it under heavy load.

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It’s a power loss caused by software, a fault error code.

You can also control the length of time it lasts. I usually turn this down to 85ms from the default 500ms.

Can be many things. Bad settings, loose connections, too high of a load, even the wrong kind of bumps/pebbles can exacerbate other things to cause it.

First thing I’d check are your settings, then connections.

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I was throttling on a downhill slope, so I shouldn’t have been pulling toooo many amps… I’ll examine the connections regardless.

Were you at or very near the board’s maximum speed?

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Yes.

Did you have field weakening turned on?

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Try changing Maximum Duty Cycle to 16% and Duty Cycle Current Limit Start to 14%.

Then test out the top speed behavior at a crazy low speed you can easily run off if needed. Try to replicate the problem and/or see if it exists.

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Could it be thermal throttling? I’ve had motors thermal throttle one before the other, which also threw me into a wobble.

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I suppose it’s possible, I didn’t check temps afterwards

But it was only 2-3 miles into my ride on the new Reachers, bout 45 degrees F outside… not really likely imo

You should check what the beta value is for the thermistor in your motor and compare it to the one set in your ESC.

If it’s off it could think the motor is overheating when it isn’t

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oh jeez, can u explain this like i’m 5?

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On the bench, do your motors crackle when you hold full throttle?

I had an issue running a Ubox V1 and a UART remote that caused a similar failure mode as this, although it didn’t happen severely enough for me to fall.

Also, what FW are you running?

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