After a great first ride yesterday, which was cut short — not by Range Anxiety but by Tornado Anxiety — I had 68% juice left in my battery. I wasn’t sure whether I should re-charge or not, based on some different advice I’d heard from Brammo over the past months. But who wants to come home to a bike with 2/3 of a “tank” left? I sought the advice of Brian Wismann, a/k/a BrammoBrian on the Brammo Owners Forum. Specifically, I inquired:
I remember you had originally recommended that new bikes be ridden to within 20% of State of Charge (SOC), before recharging, and that this be done about half a dozen times. (I remember that this was an issue with Schiff’s bike during the first days of the shockingbarack trip). But then, I recall that Brammo was pre-conditioning the batteries so that new owners could plug in whatever the SOC was.
After yesterday’s ride, I’m at about 68%. Should I go ahead and take it down to 20%, or not worry about it.
I can understand your confusion over “conditioning” the batteries. Our own understanding of the battery system has improved since the first posting went up about this after first customers received their bikes. The information that’s been provided to date is not wrong, it just needs further clarity.
Brammo does, in fact, “condition” batteries at the factory, but I still think a conditioning period by the customer is the best way to get the most out of your bike. It is the discharge (riding) and charge cycles that work to balance the voltage between strong and weak cells and get the pack working as a “team”. I used to believe that it was necessary to take the bike down to below 20% for this conditioning, but we now believe that as long as you take it below 50% SOC (state of charge), you’ll be just fine. I will admit that part of the recommendation of taking the batteries below 20% was to get new customers over the “range anxiety” barrier and get them more comfortable with riding the bike at a lower state of charge. If you leave your house and ride until you hit 50% or so and then turn around and go back, you’ll end up with a pretty good “mental map” of your real riding range. So… it’s not only the batteries we’re conditioning here… it’s the rider!
Also… leaving the bike on the charger as long as you can (overnight) will allow the BMS to work its magic at the end of the charge cycle and begin balancing. You can check the balance of the cells with the “secret” tank button press (8 seconds while the key is in the ignition in charge mode), where the high and low voltage of the battery stack will be displayed. You’re looking for somewhere around .050 – .070V difference between the two.
Given this information I made the ‘zecutive decision that it was crucial to head home at lunchtime, take the bike out for a quick ride — for battery-depletion purposes only — and start charging. Traffic was a nightmare, of course, so it took about half an hour to make the approximately 10 mile trip. I must admit I felt a bit guilty: here I was, using about a gallon and a quarter of gas, emitting some noxious vapors, etc., just to get home for a short joy ride battery depletion exercise. I promise to do better in the future. Really.
Took my second ride, this time heading north to find some country roads to bomb admire the scenery while reducing the SOC of my battery. Have I mentioned that I LOVE LOVE LOVE LOVE LOVE LOVE LOVE LOVE LOVE LOVE LOVE LOVE LOVE LOVE LOVE riding this bike? However, I was about a mile from home when some inattentive hag person tried to pull a left turn in front of me, as if I were invisible. Thanks to @NomadRip and his tweet to me (“Just ignore all those who say you are invisible when you ride. They can ALL see you and they are TRYING to hit you”), I had approached that intersection with the preconceived notion of disaster and hit the brakes. Not really a “close call” but close enough to drive home NomradRip’s point — Be careful out there.
By the time I got home, I was down to about 20% SOC and was able to begin the charging process. Even though I thought I knew what to do, I ended up having to print out this page and follow the step by step:
Apparently, I wasn’t turning the key quite far enough. Once I figured that out, I pushed the Tank Button (Step 2) and heard the familiar sound (I must coin a term for the sound…. Wissbang? Whooshboing?) and got the prompt to plug the AC cord into the wall. Charging commenced.
The dash said it would be about two hours, so it should be in the balancing mode by now, and ready to ride with 100% SOC whenever I get home and can slip out the back.