68 Wh/Mi Reading from App. Is that Legit? + some more q's

Just recently got a wireless module for my Tenka (I know, it sucks) and went on my first ride. I used Yours Truly to track it, pretty sweet app.

I noticed a few things though:
My ESC speed is waaaaay off of my GPS speed. (Ex: ESC Max: 8.4mph, GPS Max: 27.9mph). Is that normal?

My efficiency was 68 Wh/Mi, which seems really high imo.

There was no temp on the local motor but the can motor had temp data

I rode some off road, mostly on road, but there were some big hills, elevation 1400ft up/down, average speed of 18mph. Could the hills be what causes the high Wh/Mi?

Board Specs as follows:
Superbeast 6374 140kv Motors
Focbox Tenka
16t/64t Puleys
8 inch Tires at 32 psi

Vesc Settings:
Vesc 6.02
Motor Amp Max - 60a
Motor Brake Max - 40a
Battery Amp Max - 40a
Battery Brake Max - 35a
VSS Sensor Mode

Now I can chalk this up to the Tenka doin Tenka things (It will be retired soon) but im hoping its something I can tune out. I have a feeling the battery might be older than the guy told me it was or he stored it at a bad voltage, it feel like it should be able to do 20 miles but it struggles to do 15. If i’m choochin it will be 10 miles. And I do notice sag. After about 2 miles of me riding I can feel my top speed diminish by about 4 mph.

I will do more testing as this is my daily ride to work, so I will get more data in more normal circumstances (flat ground, constant speed) and update as I go.

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This is likely caused by the VESC not knowing your gear ratio and tire size.
If the vesc believes you’re running 100mm urethane wheels when you’re actually running 8inch (200mm) pneumatics, it will count the number of motor rotations and calculate your speed as half of your real speed (because you’ll go twice as far per rotation)

This is also likely caused by the VESC not knowing gear ratio and tire size, if you’re not getting abysmal range it’s likely that the vesc thinks you have smaller tires/a shorter gear ratio which leads it to believe your rides are substantially shorter than they actually are.

If you use 600wh to go 20 miles, while your VESC is only counting speed at 1/2 what it should, your VESC will think you only went 10 mi and used about 60wh/mi.

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We can figure out a reasonable estimate for your efficiency based on this. If you are getting around 15 miles from a 12s4p of p42a cells, you’re getting something around 50wh/mile, which isn’t good, but it’s better than 68wh/mile.

Yes, this will usually make your efficiency worse.

Bump those tires up to 40 psi to improve efficiency.

Like @Egtscs said, make sure you have the right settings in VESC and Yours truly.


Ah, I am a dummy I didn’t scroll all the way down on Yours Truly. Wheel Size is not right. I will do another ride and see if it fixed it.

Ill pump them up to 40psi and give it a go too. Hopefully its less than 50 wh/mi.4

All that said any ideas on the temp sensor?


I am afraid non existent temp sensor readings are usually not caused by software but by hardware. You can check if the sensor wires look damaged, maybe the wire is broken in one point, or maybe the motor itself has a bad temp sensor. Are your hall sensors both working? The startup is smooth?

Like others have said, check vesc settings, you need to make sure the gear ratio and wheel size are right, as well as motor pole count (usually 14, and I don’t know if it detects right if you put this in wrong)

A tad high for sure.

This is most likely the reason for the efficiency. I get about 58wh/mi on my work commute route, in in which I have 900ft elevation gain, however, I’m usually travelling over 30mph (black mamba DIY)

Hills absolutely shrek your battery and efficiency, especially accelerating up them. The 8 inch tires are also not the most efficient thing in the world at that PSI