Just got a Shred

[patcheung]

My battery LEDs always show more. When I asked s604 about that they said that they wont agree because the 4 LEDs measure something else. They didn't say what.

That's weird...they won't tell you what those LED's mean? That's a very strange answer. Perhaps the battery manufacturer can tell us what it means.

So yesterday I started charging it immediately after I saw the empty blinking batter indicator. I thought maybe if it was plugged in, it'd trigger something in the display to readout correctly. Well...no immediate change. After 15 min, I checked again, went up about a bar, and turned the display back off. Checked again after 30 mins, showed about 2 or 3 bars, then turned the display back off.

Then after about an hour of charging, it showed around 3 bars...but this time I just decided to leave the display on to see if anything happens. Oddly, after just watching the display for about a min, I saw the bar climb from 4 bars to full in couple seconds. I'd like to think the power of my mind charged the battery to full as I stared at the display...but I doubt it. I think something weird is going on between the signal from the battery to the display. Or, there could be a battery leak, and my battery went from empty to full in about an hour.

I ended up taking it for about an 8-mile ride. Today battery seems to be about where I'd expect it to be after that ride...2 bars down from full.

Another bit of useful information perhaps...I have the higher capacity battery.

 

[DaveS]

I just didn't think to ask what the LEDs mean. Next time I'm on the phone I'll ask.

So from your post, we've learned something. And this is what I suspected from my testing also. When the display showed empty, the battery wasn't really empty because it's physically impossible to charge it from empty to full in 1 hour with a 2 amp charger like we have.

I have been measuring the pack voltage on mine while it just sits in my garage (both on and off the bike), and the pack voltage has remained steady (to within a tenth of a volt) over the last few days, even though the display is still dropping 1 bar per day. So I think the actual cells are fine, it's just that the display is reading incorrectly. The display issue doesn't concern me too much, but when the display shows empty, I think it reduces the power available to the motor. I say this because when I took mine out after a week of inactivity, and the fuel gauge started blinking empty, my bike acted sluggish, and would only do 12 mph using the throttle. I headed straight home (I was only a few blocks away). When I got back I measured the voltage and it was more than 48V (i.e. it should have had >40% energy left) so for me, this is the real problem. I don't want to have to nurse the bike home when I still have lots of energy left. If someone else can confirm this last part, that would be awesome.

 

[Seeker]

Testing battery pack vs display is going to take awhile for me more then likely. Dave will hopefully get his done sooner.

I charged mine 100% today and fully charged voltage was 54.6 and that is what it should be. I let it sit for 1 to to 2 hours (not on bike) and voltage was 54.4.

Went for short 6.4 mile ride half of which was on a trail I had never been on. There were lots of downed trees I either had to almost drag bike under or over and it was hot so it cut my ride short.

Display showed 9 bars and voltage was 52.8 so that's about right I would think.

I am taking the pack off after every ride for the first testing.

Do have a questions. After the battery starts flashing and bike slows down any idea how far on level ground before bike cuts off? Also does display have bars left when the pack starts flashing?

Also any idea what low voltage cutoff voltage is? 20% should be around 42.1V.

Hope can get out in a little while and finish draining the pack.

 

[Seeker]

Hey Dave you posted while I was typing.

Wow display is a problem if that's the case. How about if you take pack off between rides until problem is resolved but that's not a great solution either.

 

[DaveS]

How about if you take pack off between rides until problem is resolved but that's not a great solution either.

I don't think there is much parasitic load on the pack when it is on the bike, so taking it off doesn't help.

After the battery starts flashing and bike slows down any idea how far on level ground before bike cuts off? Also does display have bars left when the pack starts flashing?

Well if it has a half a packs worth of charge in it, it could go really long time. Oh, and to be clear, it's not the pack that starts flashing, it's the fuel gauge on the display. It goes like this ...
ten bars in a solid outline of a battery
nine bars in a solid outline of a battery
...
one bar in a solid outline of a battery
zero bars in a blinking outline of a battery (this is when my bike started getting slow)

This caught me off guard, so I wan't thinking straight, but when I get close to zero again, I'm going to see if there is a hard transition between one bar and zero (indicating more of a energy conservation mode kicking in) or if it's gradual indicating more of a real battery depletion, which I don't expect.

I don't know what the value is for the low voltage cutoff on the Shred.

 

[Seeker]

Thanks for info. I was thinking maybe the display bars would quit going lower if the pack is not left on bike.

Anyway I am going to leave pack off between rides and see how display acts. Hope firmware can fix if this is a problem.

 

[DaveS]

More data to absorb.
I charged my pack a week ago and it read 54.5 volts, which is good. Full charge. Then took it for a 14 mile ride. It read 8 bars left, and 50.5 volts, so I let it sit for a week to see what happened. Every day I checked it, it dropped 1 bar on the display. This morning it was 2 bars left and voltage read 50.2V. This is a pretty tiny drop in voltage in the grand scheme of things, especially compared to dropping 6 bars on the display. So I took it for a 10 mile ride and, just about the time I was getting home (I was on 1 bar left) I noticed that sluggish feeling again, so I tried the throttle and it would only get the bike up to 15 mph, I stopped and checked the pack voltage. It read 47.5 volts. when I got home, I figured I would run it around the block a few more times and run it down to empty. Well, it ran for another 10 miles (in the empty blinking display state), and was still only down to 46 volts. I used full throttle the whole time and averaged between 12 and 16 mph. I finally gave up trying to run it to empty. So I think what's happening is, yes the display is not accurate, but the limited power mode is probably just the controller reacting to a weak battery. It just wont run the battery hard when the loaded pack voltage is low. I can't read what kind of voltage drop the battery experiences when using full throttle, but if it's something like 43 volts, I can imagine a soft LVC gets tripped and puts a limit on the max amp draw. The good news is when I did notice the power drop, I had lots of juice left to get home albeit at a slower top speed. This is on the standard 10.4 Ah sized battery.

 

[Seeker]

Great data. Hope that is true I guess about a soft LVC. That's better then kicking in a real LVC that would probably need a charger to get going again.

So slow mode came at around 24 miles. Wonder if that would be the same starting with 100% charge and 24 miles without stopping or letting bike sit and display going lower.

All said 34 miles not bad on 10Ahr battery and you quit before it was totally dead.

 

[DaveS]

So slow mode came at around 24 miles. Wonder if that would be the same starting with 100% charge and 24 miles without stopping or letting bike sit and display going lower.

I have a feeling you are right. I think it would start slowing down at ~24 mi regardless of the week long gap, and independent of the display. One of these days I'll take it for a daylong trip and see what the range is. It's so dependent on terrain, how energetic you are that day, and average speed though, that I'm not sure how repeatable it will be.

 

[towelie55]

Hey im having the same problem as you guys. Battery level dropping from just being idle. I emailed Surface about it and waiting for answer about the issue. Did you guys all confirm that its the display or battery? either way Im worried about getting stranded or having to check my battery hours before i need to use it to make sure its charged.

 

[DaveS]

I think it's just the display. I also don't think you will get stranded, but so far I'm the only one who has tried to deplete the battery and I got 34 miles before giving up (it could have gone farther). 10 of those miles was with the display on empty. I encourage you to charge it all the way up. Take note of the mileage on the display, and drive it over the course of a week or so until it runs out of juice or becomes so sluggish that it's just no fun to ride. Keep track of mileage when it goes into power saving mode (easiest way to tell is the throttle wont take you up to 20 mph / 32 kph) and also your max range. Post numbers here for others to compare with. Not only will this help the community, but it will give you a benchmark for how far your bike will go under your driving conditions. Thanks.

 

[Seeker]

Ok I ran mine basically all the way down. The display was flashing empty at around 18 miles on the display. I rode around 2 more miles before I could check voltage and it read 48 .2. Also the led's on the battery showed 3 lit.

I kept riding using the throttle a lot. I past the 24 mile mark with 20 mph still there. At around 28 miles mine cut out with no throttle or assist available.

Turning off the display and back on the throttle and assist would come back. If I used throttle past around 16mph it would die again but would work at slower speeds for awhile. I never had the slow mode unless I kept it slower myself.

Before I got home I could not use the throttle at all without the cut out problem but peddle assist got me home ok.

The voltage when I got to the house was 44.5. I only made 30 miles and this is with the 14Ahr pack.

 

[jazz]

I would say for the how fast you were going and using mostly throttle 30 miles out of 14ah is good

 

[towelie55]

so seeker what was your conclusion? Was it the display or the battery?

 

[Seeker]

Because the display looses bars overnight even without the battery attached. I started out today with the display showing a little over 6 miles and 2 bars on the battery. The battery was blinking empty at around 18 miles and I knew there was a lot more battery left.

I wanted to drain the battery all the way and see if mine went to slow mode like Dave's did. His I think went into slow mode when display started blinking empty and at around the 24 mile mark. Mine did not ever get to slow mode it just cut out at the 28 mile mark. But I have the 14Ahr and he has the 10Ahr.

I had to turn mine off and back on a few times to get home. Battery ok I think. Display just not accurate.

I used the throttle a lot today trying to drain the battery so more effort would give more miles.

 

[towelie55]

Yea its def the display not reading properly. I took the battery off to fully and when i placed it back on the bike it showed half a battery still. Anyone know how to fix this?

 

[Bob H]

I don't have a Shred but after reading this thread, it is obvious that Surface 604 has a problem with this bike. What do they say about this problem? I have a Colt and Surface 604 has been very helpful the couple of times I've called. Anyway, I hope you all get this sorted out as the Shred looks like a very good bike.

 

[dgstan]

For the record, I haven't seen any of these types of issues. I'm not doing any specific testing, but I charge the battery, put it on the bike, and the next morning, it still shows full. I'll ride to work (8 miles) and leave it sitting on the bike all day. The battery level will be exactly the same as I left it when I leave for home.

Is there any specific scenario you'd like me to test? I do have a voltmeter laying around somewhere too.

 

[Deleted member 4210]

One quick note about your 'out of the box' experience. The vast majority of Surface products are shipped through dealers, so end users buying direct will have to do what dealers already know to do in terms of setting up the Shred. Also on the tire settings, while these are 27.5" tires, the 3" diameter actually has a different diameter and circumference than a typical 27.5" tire. The display control settings related to tire size are only designed to be a close approximation, and depending upon the other settings and how the motor is tuned, the tire size selection up or down slightly, wont make a significant difference. But no one getting this as an end user and directly from Surface 604, should expect it to come completely or properly set up to ride right away. I would definitely say this is more of a road or maybe even good 'gravel' ebike than any sort of true 'MTB', but it happens to be awesome for the crappy roads we have here in Illinois, that are almost like riding on gravel or 'off road', given the potholes, even near 'craters', terribly positioned sewer grates, and all sorts of cracks and patches. (we have a terrible freeze/thaw climate here, so its a killer on roads anyway, but a LOT of the state money goes to fill pension 'gaps', so there probably isn't much left for things like roads or anything else that is really important...lol...you'll get this sarc if you are from IL)
P.S. Nice photo !

 

[towelie55]

I did get an email back from surface, their is indeed an issue going on with the displays, they are still waiting for a response back from i believe bafang on how to fix the issue. Hopefully its something simple, thought about maybe switching out my display for a different bafang display but the only one i think i would want is the one on the juiced bike considering its smaller and hardly noticeable.