Watt Wagons Critical Product Availability Status

Found this just for a quick reference.

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Looks like there's been a lot of conversation since I've been on! Also looks likes it's not super important so I didn't bother reading it all :D
think I'm only caught up to page 14 but I did skim a bit...

Anyway, got an email regarding updates - any news is good news, even if timelines changed (controllers expected mid-Jan now first week of Feb, no biggie) it's good to be updated of changes to temper expectations. A very simple thing to do and yet it makes a big difference.

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"Peace is not merely a distant goal that we seek, but a mean by which we arrive we arrive at that goal"
 
I had to take a break from all this with other stuff going on in my life, knowing that conversation here isn't meaningfully changing the outcome, and many are objecting to my updates. That said, there's been some movement to update on.

My recent outreach wasn't ignored. Pushkar changed communication channels to reply to our email thread without warning, so his new unexpected conversation thread from another email address was picked up by my spam filter. Since then...

  • The right saddle colour was ordered, and delivered to WW (after the suggested date).
  • Wattwagons leaked my personal info to BarnBoy
  • There has been some minor communication gaps around my bike within wattwagons (relating to decals and grips) - not a big problem on its own.
  • I've been told they're out of stock of the Supernova lights I ordered. I've asked how it's possible this is only being reported at this point, over 7 months after ordering when I've been told the bike is just waiting on x as many times as I have been and when at time of ordering, and even now, the lights show as 'green' on the availability page.
And now @WaxedWookie is also radio scilent after he logged in on Saturday to find all his blamestorming was his own fault. He even mentions details of the missing email in his writings. But he still has not responded to the multiple emails from WW to close this chapter… (yep, his fault too!!!)

Pushkar responding to an email thread via a new channel without warning is my fault? Are the delays on me too? How about them leaking my personal info?

As I said before yet was flamed, alternative communication is available if you choose to use it. Your fault for assuming that continuing what was not working for you is the right way, and then defending it….
As I've said, I've tried various emails, support tickets and live chat to no avail before ever posting here - I requested a phone call that never came, and I've asked for a contact number in this thread. These alternative channels (what's the official one if these aren't) are all a pointless aggravation if WW don't respond to them.

I'm glad those of you that got your bikes are enjoying them.

@loamoaf - you didn't miss much - TLDR: argument whether the complaints about the poor comms and missing bikes is warranted. WW continue to find new parts missing from my bike.
 
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Sorry to hear that. I was hoping you were going to be out in the bush, shredding some trails.

Quite a shame that ww does not seem to be able to keep up with the inventory that they are going to need to build their bikes. 7 months ago they should have began sourcing the products that they offered and you chose. Waiting until the bike is all but done to try to order the correct seat and light seems like a good way to exasperate an already difficult supply chain problem.

Good news, I had to reach out to supernova last summer. They were receptive and sent me a tracking number the next day for the high low switch that I needed to order. It arrived within a week. Hopefully they are on the same timeframe now.
 
Is it just me or does the voltage/range change not seem quite right? My understanding was that generally speaking, higher voltage generally leads to less strain on the motors and less wastage as current-driven heat, both of which would shorten battery life (assuming the only difference is the wiring of the cells).

Is there anyone more experienced with this stuff that can weigh in, or any real world tests to look at?
 
Not really, it is all about which cells are used, and the S-P configuration.
48V means less serial connection, but more Parallel ones depending on the cells sustained draw and capacity that can lead to a pack better suited to the bike need.

For example, a BoxxBike uses a 12S-12P battery with 1800Wh capacity and 8kW peak power
 
Yeah that makes sense - if the lack of parallel cells (because they're tied up in series) leads to voltage sag, which will stress the battery more leading to shorter range. I suppose that's kinda the other side of the coin in the example I gave in my previous post.

I suppose with this in mind, it's largely up to the riding style, so I'd be interested to see some benchmarking under different scenarios.
 
Yeah that makes sense - if the lack of parallel cells (because they're tied up in series) leads to voltage sag, which will stress the battery more leading to shorter range. I suppose that's kinda the other side of the coin in the example I gave in my previous post.

I suppose with this in mind, it's largely up to the riding style, so I'd be interested to see some benchmarking under different scenarios.
I think this is it. More parallel series means more current overhead on the cells; as you approach the CDR of a cell, the amount of energy it can deliver is decreased as is the cycle life. Some cells/chemistries handle this better than others and some are notorious for sag under load below 50% which could trigger LVP on the BMS. Another way to put it let's say your pack is built with 10A cells. a 14s4p 52V 40A battery can do 2080W and uses 56 cells, a 13s5p 48V 50A battery can do 2400W and uses 65 cells. If both these batteries are used on a 2000W setup you're near the max CDR of the 52V pack, but you've got almot 8A before you hit the max CDR of the 48V pack. Now make it 1500W and you're only going to need 6.25A per cell which will definitely get you more range than on the 52V which would be 7.8A from a 10A cell. Again some cells are better than others - let's take a look at two here

The Samsung 30Q can deliver far more energy and remain much cooler when you're only asking 10-15A from it as opposed to 25A (using 3.1V as a LVP for 20ish% floor. Normally Mooch throws a nice little 'xWh @ nA' boxes but for the 30Q there isn't one. For the 40T however you can see how the available energy at 30A (near its 35A CDR) is less than 73% of what you'd get asking only 10A from each cell. 20A isn't as bad at 87.8% the energy at 10A. 40T's aren't the best example though because that's typically more current than you'd ask from an ebike. Point is though, if you can stick to under half the CDR for the cells then you'll get at least ~20% more range than than if you were riding the limit frequently.

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How pack is configured doesn't matter to individual cell. A 10s2p pack or a 2p10s pack can put out exact same mount of power. In fact you don't even need to know how pack is configured.. you can just say a pack with 40 cells is putting out 500 watts... each cell is contributing 500/40=12.5 watts and if cell is at 3.7v that's a 3.4amp load on each cell.

So when comparing 52v 14s4p pack to a 48v 13s5p pack really you can just say.. its 56 cells vs 65 cells.

Not only will 65 cells have more 16% more capacity, but for a given load, eg 500 watts, each cell will see load 14% (8.92watts vs 7.69watts) smaller.

Yes in general with all else equal more voltage / less amps will have lower line losses and be more efficient. But wires here are short, line losses will be small, voltage difference is tiny.. the effiiency difference will be pretty minor. I've seen many try to prove 6S is more effiicent than 4S for in RC cars/quads... like even though you know it is, its so hard to get good enough data to show it. And that's a 50% voltage difference. This is 8%.

56 vs 65 cells is far more important.
 
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You are right that at exactly the same number of cells there would not be a difference in extracted watts per cell.
That said, torque needs Amps, so if a motor needs a lot of amps, and the pack has a small number of paralleled cells , the controller will have to convert the higher voltage low amp from the battery into a lower voltage higher amp for the motor.
I don't know what the impact from that is, and whether it justifies trying to have a pack that can deliver more amps directly out of the battery.
 
@bexamous the greater number of cells obviously helps but I try to break it down into energy per cell to show how changing the pack configuration leads to efficiency gains. The 13s5p pack not only has more cells (and thus more energy at the same power draw per-cell) but the configuration allowing for more overhead on the available CDR also means you get more energy per cell at the same power draw per pack. Once you get a pack big enough to compare 52V vs 48V with the same number of cells you get ridiculous amounts of power & current overhead that the analogy loses its relevance in regards to ebikes (sure people have 2kW packs on their bikes but if they're anywhere near the CDR of those packs that's emoto territory)

So not only would the 48V (65 cell in this scenario) pack have 16% more energy at the same power draw per cell than the 52V (56 cell) - it would be able to deliver even more energy at the same power draw per pack because in addition to having more cells you are getting more energy per-cell. I can see this being preferrable when you have some frame sizes with shorter down tubes where a 13s5p is possible but a 14s5p is not, and of course in reasonable urban commuter/mtb trail cases you don't need 2500W+

Yes I know we need it, but we don't need it. But we do need it.

I'm honestly unsure if battery current & voltage = phase current & voltage, or if the controller is outputting the same to the motor magnets regardless of whether it's hooked up to a 52V or 48V. My assumption is that the battery voltage does make a difference in that motor Kv is a relevant topic of discussion in the sphere of ebikes but who knows (no seriously, who knows for sure and can chime in?)

I'm also unsure if there's any ability to change the X1 controller battery voltage after the fact with the programming harness or if the controller requires the motor's factory voltage setting to be the same (48V motor with 48V controller) or if that too is just some settings in the text file on the Bafang controller that can also be changed by the end-user.
 
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I just had my configuration changed remotely from 52 to 48 V. on one of my bikes. There is a small drop in performance although to be honest I felt the 52 V early model programming Pushkar used was too powerful. Eco 3 would lift front wheel if you were not careful. The 48 V system needs to be in the turbo mode before the front wheel comes off without lifting. overall I think this is a much better set up for my riding. I am rarely drawing over 1500 W. I don’t have any real testing on it yet for range but I suspect I will gain approximately 20%. There are nine more cells in the 48v pack however it does not have the smart a BMS. The smart BMS takes the place of 5 cells. I hope to get out riding soon and will post some results as to the differences in both bikes.
 
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