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i’m positive that it’s output - or at least an estimate thereof. the math aligns very closely with predicted speed and power requirements going up steep hills slowly, which is really all about gravity and weight. the documentation on the system also specifically mentions a motor torque sensor -...

important distinction - 10 MPH, not 6. 6% grade. i don't know yet what it'll be at 6mph (which is more like a 10% grade, coincidentally) since i didn't get good battery values for that first test. one interesting thing about the mahle data is that the WH capacity doesn't seem to go up if the...

here's an example with efficiency. i am missing a little motor power data at the end due to user error (the chart is a little shorter in time than the math), but no reason to believe the relationship between speed and power would suddenly change. red line is motor power. blue line is speed...

yep, that’s a good method if the bike goes by itself! if you need to pedal also, then of course you need to know how much work the rider is doing. without a watt meter, i wonder how accurate the SOC estimates from these things are…

i was surprised to see (after you pointed both of them out to me) that bikecalculator seemed to diverge from gribble, but the real issue is just not knowing all the values they use for the drop downs. some of the CdA values are higher than i would have guessed but not unreasonable. my own...

you just keep pulling out numbers without easy reference. 40% is crazy for loss, EIA estimates five percent. https://www.eia.gov/tools/faqs/faq.php?id=105&t=3 got a better, authoritative source? even if it was 40%, the total number for every passenger car mile driven is not even half of the...

you need a real ID or passport DOD ID card or a handful of other rare types. basically a real ID or passport. don’t bring any weapons. you can’t check really large batteries in, they have to be with you and removable. liquids need to be in small containers. they’ll ask you to take off your...

right, the question is are these small hub motors geared internally in a way to be efficient at, say, 6mph - which is around 75 rpm here. i assume it’s internally at least 5:1 on a motor this small so the range we’re asking it to be efficient in is roughly 350 to 1,150 RPM.

take a look at the ourworldindata link. the numbers aren’t quite that extreme, and it seems a well documented source. i agree that aviation, marine, and other industrial uses are going to be difficult. other transport is relatively easy as is electricity for general purposes.

more questionable numbers. here are the real ones 3.2 trillion miles driven in the USA per year. this figure is widely available. a good electric car can be expected to get about 4 miles per kwh in the near future. many already do better than that, some worse. assume 10% energy loss (DC fast...

where do you get this? many different sources show wind and solar at around 15% of electricity generation, up from basically zero just 15 years ago. yes, a long way to go but solar capacity is increasing incredibly fast, especially outside of the US. even using the more general definition of...

there was an interesting discussion here https://forums.electricbikereview.com/threads/another-new-tq-motor-hpr40.57935/page-13 about climbing hills on lightweight hub drive and mid-drive motors, especially the new TQ HPR40 which looks very, very promising, and @Yako is currently riding. i...

but the bike already has BLE. it’s really just a need for / use of a standard profile for BLE. this already exists for many bluetooth fitness devices - like cycling power meters. phones have bluetooth. smartwatches have bluetooth. bikes have bluetooth. cycling computers have bluetooth. other...

yeah, it’s kind of an interesting artifact of where we are in the technology landscape. the ANT standard has been around a long time, and it’s very, very simple. European regulations around wireless communications require encryption going forward (EU RED) which would be difficult to implement in...

the 4 and 4.1 meter/wh values are very interesting. if you’re doing half the work yourself, and the total load is 125kg, that’s 70% efficiency! of course it could be way more or less if you were going fast or doing less/more of the work yourself.

when you consider that the cheapest accurate power meters on the market cost quite a lot more than mahle’s entire bottom bracket with the sensors (which is very cheap - $200 at retail) it makes sense that it’s a blunt instrument. given similar experiences with the specialized ones (which at...

i just don’t believe that the TQ40 is only 65% efficient. so far we have a test report that seems to show 65%, specialized claiming it’s 65% (lol, wouldn’t trust that one) and TQ claiming it’s 90%. that 65% test showed a peak of 250w output power (isn’t supposed to max out at 200?) at 400w...

i didn’t realize that was your review ! fantastic and thank you for producing it, lots of work no doubt. the rider input number in the mahle app is total nonsense, it comes from some kind of sensor in the bottom bracket and is way off. i can say this pretty definitively since i moved the...

Cool review. It appears he used about 75% of the range extender (100wh ISH) tooling around and then getting to the top of a 1300’ (or so) climb. More or less tracks with what you’d expect, depending on how much he used before going up. He also notes that he did it on level 2, but i don’t think...

i’ll add that canyon uses roughly the same 6,000 foot metric that we arrived at in their literature, noting that the range extender exists to let you exceed it….