How much battery sag is too much for a 3 year old battery?
- Thread starter Ghost1951
- Start date
Did you hear that? He clearly said "Time of Stop" set to 25 means certain death! 
If it wasn't one of the voices in my head, like the one which says the cookie monster is the antichrist - I've just eaten an entire bag in the same manner, I blame cycling.
I should get around to making a video about how to limit BBSXXX throtles to UK legal 6kph. I don't know how much interest there is TBH, not a question asked on many threads over the past three years by anyone other than myself. I could do a voiceover using my Darth Vader impression.
If it wasn't one of the voices in my head, like the one which says the cookie monster is the antichrist - I've just eaten an entire bag in the same manner, I blame cycling.I should get around to making a video about how to limit BBSXXX throtles to UK legal 6kph. I don't know how much interest there is TBH, not a question asked on many threads over the past three years by anyone other than myself. I could do a voiceover using my Darth Vader impression.
Bit squirrelly balancing on steeper inclines than this at 6kph on 20" wheels, more zigzaggy. Gear 4 of 8. After the cat:
(Accidentally 720p)
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Weirdly compelling back ground track there.
Can you post those settings for the throttle and any otyers that are needed?
My throttle would not pull me at all. It is strictly a walk beside function. The other day, i had to attempt to get off on a steep start three times on PAS before successfully pulling away. It was a bad hill mind.
Can you post those settings for the throttle and any otyers that are needed?
My throttle would not pull me at all. It is strictly a walk beside function. The other day, i had to attempt to get off on a steep start three times on PAS before successfully pulling away. It was a bad hill mind.
Despite your larger wheels, heavier bodyweight, and lower controller amperage limit, settings on post #89 will probably make your throttle work similarly:
https://www.pedelecs.co.uk/forum/threads/how-much-battery-sag-is-too-much-for-a-3-year-old-battery.47298/post-717094
It's a very old one I made years ago using the Korg MS-20. The sounds of me sniffing would have been even more offputting.Weirdly compelling back ground track there.
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The cat was good. Is it yours? That reminds me. I have some CATching up to do:
When she was a very thin and scrawny looking hungry tiny kitten, she followed my friend's son home from the chip shop and never left. Despite growing up, neither has her son.
I was forced to utilise my telepathic superpower to communicate my intended trajectory until she moved out of the way.
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You'll be able to balance better at such low speed uphill, on your larger wheels. I mostly used gear four out of eight, 52T>18T = 57.8 gear inches on my bike, throttle managed all hills tried during this short test.
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This has surely got to be the most boring set of low speed tests ever on the forum!
My DPC18 display doesn't express wattage as a number. However, switching on the bike with the Speeed app connected shows wattage used by the throttle on the tablet display - gave it a quick burst while holding the bike down with rear wheel wedged between two steps on the staircase, and saw over 526W displayed... therefore I think there's more power than is available to walk assist...unless of course the throttle is operating while connected to the app at full power, because throttle designated Level 0 isn't available, because the display isn't connected.
Will try morethrilling slow thottling ascents with these settings soon. "Speed" mode this time, to see if there's less high torque applied initially than with "Current" mode, which led to internal motor gear grinding (at least I think that's what the sound was when starting throttled on my highest gear). I'll try lowest gear and highest motor RPM for 6kph, which it should reach on all hills: 52T>32T on my bike = 32.5 gear inches.
The gear sensor will automatically cut motor power as I switch to higher gears - perhaps this could become the new plan for hill starts, after having stopped on too high a gear: deploy kickstand and lean the bike's rear wheel off the ground, throttle to to a lower gear, kick the kickstand back, throttle start then pedal assist auto gearchange uphill laughing maniacally.
I'll have to find quiet steep hills, as I don't want to zipzag off-balance into traffic on squirelly 20" wheels. In the dead of night sometime maybe.
My DPC18 display doesn't express wattage as a number. However, switching on the bike with the Speeed app connected shows wattage used by the throttle on the tablet display - gave it a quick burst while holding the bike down with rear wheel wedged between two steps on the staircase, and saw over 526W displayed... therefore I think there's more power than is available to walk assist...unless of course the throttle is operating while connected to the app at full power, because throttle designated Level 0 isn't available, because the display isn't connected.
Will try more
The gear sensor will automatically cut motor power as I switch to higher gears - perhaps this could become the new plan for hill starts, after having stopped on too high a gear: deploy kickstand and lean the bike's rear wheel off the ground, throttle to to a lower gear, kick the kickstand back, throttle start then pedal assist auto gearchange uphill laughing maniacally.
I'll have to find quiet steep hills, as I don't want to zipzag off-balance into traffic on squirelly 20" wheels. In the dead of night sometime maybe.
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I am back with my kit e-bike again and have been riding this morning before the horrible downpours arrived (right now it is torrential outside). I have not yet addressed the changes to throttle which we were discussing. I am in an undecided state as to whether I need to. I generally don't require a throttle, and as set up, my bike has a very low power, walk throttle which functions now to 3 miles an hour.
The only things that would tempt me to make a change would be the problem of getting rapidly across a busy A road and the problem of starting off on a very steep slope.
The other day I had to cross the busy A69 which has traffic doing 55 and 60 miles an hour. As I did it, I was thinking how a smarter get away would be a good idea.
Also, as I mentioned elsewhere, I also had to get started on a very steep track and it took me three goes in bottom gear to get away. Having the motor able to start powerfully, without me getting a half a revolution on the crank, would have got me going first time.
The only things that would tempt me to make a change would be the problem of getting rapidly across a busy A road and the problem of starting off on a very steep slope.
The other day I had to cross the busy A69 which has traffic doing 55 and 60 miles an hour. As I did it, I was thinking how a smarter get away would be a good idea.
Also, as I mentioned elsewhere, I also had to get started on a very steep track and it took me three goes in bottom gear to get away. Having the motor able to start powerfully, without me getting a half a revolution on the crank, would have got me going first time.
Even with "Start Degree" set to 4: After stopping on my gear 4 (57.8 gear inches) or lower, starts on level road were fast enough - pedal assist starts faster now with "Start Degree" set to 2. Feels like it should be possible to accelerate a little bit faster from a standing start with 6kph limited throttle + pedal assist, but I haven't bothered to do try this much because I don't really need to start much faster than I can already - knowing when to let go of the throttle while pedalling is key, so that pedal assist shoots you forward when throttle stops.
Unless the battery is depleted, I hardly ever need to walk my bike, switching off or toggling to a non-pedal assist level seems wise. Due to my 20" wheels and newly low bodyweight, the lowest gear I've ever needed for a standing hill start is my gear 2 = 40 gear inches... which is now much easier to throttle to after leaning the bike on it's kickstand, with the gear sensor automatically cutting motor power between gears to prevent crunching.
Throttle hill starts are possible on highest gears, albeit with what sounds like internal motor gear grinding. It was the same outcome throttle starting on my highest gear on level ground. The preceding might be less grindy with speed control, I haven't tried the new settings shown above yet.
I've yet to see if a 6kph hill climbing throttle will help the 90kg trailer hauling sharp bending uphill road past a gate maneuver. Might be too slow. "Start Degree" at 2 might be just what's needed - faster pedal assist start after having stalled (ie voluntarily stopped, to prevent the trailer hitting the gate post) dragging a heavy weight, might be all that's required. Will have to see.
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I returned start degree to 4 after my bike tried to run off when the pedal moved a bit.
I just made those changes and tried it around the place while the rain briefly stopped.
I get MUCH more of a push from the throttle now, though it comes on softly because start current is now at 10% rather than 20%. I might return that back... Will try it a while first.
Weirdly, if I lift the back of the bike and run the throttle, it runs to about 5 or 6 mph which is a wee bit too fast, but on riding it with the brake on and throttle only, the power is only delivered up to about 3.6 mph. After that the power drops but the bike rolls a little faster than that.
I think this will definitely help a smarter get away or hill start now. I have not tested it much, because
What are your settings? Could you upload screenshots?
With throttle on speed control, wheel off the ground speed reads 7.6kph = 4.78mph. That's more than 10% leeway, I'll be thrown in the slammer!
On current control: 8.6kph = 5.3mph. However, setting Level 0 speed to 30% (speed control) instead of 40%results in 6.1kph. I'll test throttled level ground and hill climbing speed again at some point, with high motor RPM next time.
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Thanks for uploading your settings.
I see you did change "Keep Current" to 80%, this will result in a speed drop on throttle and all pedal assist levels after the initial short burst, because it's a global parameter. But you know your bike and ebiking needs best. I'm not worried about mosfets, as I have a spare controller.
I did notice throttle only speed at a little over 4kph ascending hills, so I have increased the controller amp limit to it's maximum of 20A, and will try high RPM on lower gears in order to achieve a dizzying 6kph throttle speed; 20A to give the throttle the best chance of load speed matching no load wheel off ground speed.
I've avoided 20A = 720W because mine's an old folding bike and I don't want it snapped in half by mid-motor torque. "Get me a Dahon sandwich and make it snappy!" or should that be crocodile? Besides, I need 2A for my bright lights... and it's only a 22A BMS - @Nealh calculated the 19.2Ah battery is capable of 25A continuous dicharge, so I'm not worried about the capability of the cell pack in that regard.
Must remember to never use Level 9, but of course I will lol. I could switch off the soldered to battery lights, before drawing 20A. TBH, 15A was enough for everything but sufficiently quickly outrunning drunk and drug maddened gremlin funsterss giving chase on foot uphill.
Have set parameters thusforthly, I'll get around to a bike ride soon possibly:
Slightly cautious increase between 15A and 20A:
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I noticed quite a power increase through the feel of the bike when I tried 18 amps max, but I have reduced the max amps back to where it was when I first looked at the settings, which was 15 amps. That is enough power for me to get anywhere I usually go and I spend a fair bit of time on hilly stretches not to say, long inclines. I just drop a gear or two and pedal and slowly ascend.
I don't think I'd be comfortable with 20 amps max... I want more range and a cooler controller - not to say cooler coils. I noticed those burned coils on a photo of an ebike hub motor on the forum last week or maybe the week before. I don't fancy that, for sure. I'm imagining one of those situations where the bike is in the wrong gear and the motor is stalled and twenty amps is being let through.... Over cautious - probably...
I've really been having some fun on this bike since I got to messing with the settings, and I only got into that because of your mentioning your experience and finding the online configuration web page which worked on my computing device. Works a treat and seems foolproof - as long as I don't enter stupid settings and blow stuff up....
Cheers.
I don't think I'd be comfortable with 20 amps max... I want more range and a cooler controller - not to say cooler coils. I noticed those burned coils on a photo of an ebike hub motor on the forum last week or maybe the week before. I don't fancy that, for sure. I'm imagining one of those situations where the bike is in the wrong gear and the motor is stalled and twenty amps is being let through.... Over cautious - probably...
I've really been having some fun on this bike since I got to messing with the settings, and I only got into that because of your mentioning your experience and finding the online configuration web page which worked on my computing device. Works a treat and seems foolproof - as long as I don't enter stupid settings and blow stuff up....
Cheers.
Throttle doesn't deliver any hill climbing at all when set to "Speed" control (that parameter as set in your post#115). Climbed all hills, albeit slowly on "Current" control. I'll switch it back, then probably disconnect the throttle - not needed because PAS is fast activating and powerful enough for most situations.
Added a bit more showing lights, to the beginning of the video. The rest is the old one badly upscaled from 30fps/720P to 24fps/1080P (cat is now slightly blurry), with slow hill climbing throttle on current control.
Drivers will be repulsed by your lollipop, if you stick it out far enough. Helps if you waggle it about. Decorating your lollipop with lights and frickin' laser beams is optional.
Added a bit more showing lights, to the beginning of the video. The rest is the old one badly upscaled from 30fps/720P to 24fps/1080P (cat is now slightly blurry), with slow hill climbing throttle on current control.
Drivers will be repulsed by your lollipop, if you stick it out far enough. Helps if you waggle it about. Decorating your lollipop with lights and frickin' laser beams is optional.
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They would cause accidents if one or all of my headlights were on flashing mode at night, which is why I keep those steady except in daylight. I've tested these lights on my driver friends, they don't dazzle. I always keep the rear red flashing, daren't have that on steady, too useful for high visibility - at night, it even works around corners. I also wear a red flashing LED sash on my back, or attached to my rucksack. They see me coming alright.
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