Adhd warning New controller...so dumb question....squirrel!

[BionicOnion]

Got my shunt hooked back up on the bike. Enjoying the new power, before peaked about 1250watts now over 2.2kw on the same old battery. So im not so worried there. I guess my question is self answering but ill make an idiot of myself anyway, its normal to dump a ton of amps and watch the wh drop much faster? Would a 3 speed switch help me reduce the draw? I figured i wouldn't get any top end since same battery, and it definitely sags more with the 45ish amp draw on acceleration. So im about 210 6'3 and the frame is a 29er. Without a straight line, life360 shows a 1 mile trip back for lunch and pulled 47wh... 67ish on return....

Sorry for jumbled thoughts
I noticed on my return trip however the throttle almost felt like an on/off switch, but still had some modulation........however at very low throttle the shunt was showing 48amp draw but only a 1.5v sag.... when I twisted oddly the amp draw reduced but the voltage tagged much more and the power calculation also dropped....

So my adhd mind is telling me my shunt wiring needs checked and retested and run it again....but otherwise im showing almost 100wh per mile? That seems insane.

 

[neptronix]

Yes. If you're pushing your motor 2x above it's limit, it's not only going to consume more power but also incur some efficiency loss - just don't know how much yet. ( a realtime read out of volts + amps is helpful ).
How's the heat on your motor after a ride? ( is it too hot to touch, hot but touchable, or warm? )

It's unlikely the problem is your shunt, it's that you're drawing a ton of power on a system that probably wasn't designed for it ( you may need fatter wires, a stronger battery, etc, since 2x the power is a big jump )

What kind of motor / battery are you working with?
And let's see a picture of your bike.

 

[chuyskywalker]

its normal to dump a ton of amps and watch the wh drop much faster?

Absolutely. You're running the system much harder, which makes it much less efficient, which means you lose more power to all the losses of the system-as-a-whole.

 

[BionicOnion]

Absolutely. You're running the system much harder, which makes it much less efficient, which means you lose more power to all the losses of the system-as-a-whole.

Thanks for the response....yes it absolutely picks up a lot better than I remember on the last frame, however i definitely need to sort the shunt out. Theres no way I was pulling 40amps and only 1.5 volt sag

 

[BionicOnion]

So today I redid the shunt wiring and connections and ran the same return trip. Much better calculations now. Not showing 2.2kw at 5% throttle lol. So my trip to work today took 11wh, which as said is approx just over 1/2 mile. I wasnt power running it just more of a gentle... easy ride. So 20wh/mile seem normal for those of you who monitor? Guess ill see after my dinner how much it takes with the gusto

 

[amberwolf]

So my adhd mind is telling me my shunt wiring needs checked and retested and run it again....but otherwise im showing almost 100wh per mile? That seems insane.

Shunt for what measuring device? Hooked up where in the system, in what way, measured and calibrated how?

 

[BionicOnion]

Shunt for what measuring device? Hooked up where in the system, in what way, measured and calibrated how?

So yeah. I have a 100a spartan shunt, inline before the battery on the negative side. I actually decided to look into things on it, cleaned up the wiring connections for it and found it not calibrated for 100a draw. So I switched from 50a to 100a. Not sure if that's the right thing or not honestly, im assuming the programming goes off a programmed value for the shunt itself. Wierd thing is sometimes it seems to measure ok, other times not. But since the clean up its not showing 2kw draw at 1v sag lol... now it seems much closer at say 250-1kw to maintain approx 25ish mph which puts me at 20-30wh per mile. That seems a little more reasonable given im 6'3 210lbs on a 29er