How to override 4% minimum charge on Trek Hyena?

[Michael Ronkin]

Hi. Is there a way to override the feature that cuts power to the motor when battery charge is down to 4%? This is supposedly to save remaining power for lights, but I haven't hooked up any lights. I'd rather get a few more kilometers from the battery.
Thanks

 

[neutron]

I'm surprised it doesn't cut out before that. 4%? Conventional wisdom would advise not running the battery down past 20%.

 

[Michael Ronkin]

What's the point of having energy you can't use? The owner's manual states there's no harm in draining it down all the way.
I bought it fir cycle-touring, typically 100k to 120k days, with hills, and I'd like to make it to my next hotel!
Of course I can continue riding without the assist a long way... if it's flat!

 

[Mr EBIKER]

Parallel it to another battery....might be dangerous..

 

[Mr EBIKER]

Misunderstood your question..

 

[pagheca]

I'm surprised it doesn't cut out before that. 4%? Conventional wisdom would advise not running the battery down past 20%.

My Trek Powerfly (possibly with the same electronics and motors) alerts me when I am at 30% and again at 10%, but I see no reason to cut power at 20%. I have never gotten below 10% though, so I wonder if the 4% cutoff also applies to mine. I guess this is to protect the battery from trying to supply too many amps at a low voltage, which could potentially damage it or cause thermal runaway.

Frankly speaking, however, @Michael Ronkin I would advise against tinkering with this limit.

 

[Hoggdoc]

I'm surprised it doesn't cut out before that. 4%? Conventional wisdom would advise not running the battery down past 20%.

I agree that seems way to low if you are trying to extend overall battery life. Typically it's recommended to keep battery between 20% and 80%. while using the bike. Any storage more than couple of days should be done and 65-70%.

 

[pagheca]

Right, but the original question is not how to make the battery last longer, but how to save you in an emergency situation, although I guess a 4% would give you 2-3 km, if any.