Here is another statement on the subject of range. The good man (with a rider weight of 75 kg) managed a continuous range of 1,800 metres in the turbo. He thinks that the range is similar to the Shimano or Bosch with more support. If you reduce the support to the level of the competition, you can cover significantly more metres in altitude than with the competition!
Dji avinox- Amflow
- Thread starter Farmernz
- Start date
Here is another statement on the subject of range. The good man (with a rider weight of 75 kg) managed a continuous range of 1,800 metres in the turbo. He thinks that the range is similar to the Shimano or Bosch with more support. If you reduce the support to the level of the competition, you can cover significantly more metres in altitude than with the competition!
As already written twice, I would not write all the above if the conditions and factors of both rides wouldn't be comparable, also I said we shouldn't jump to conclusions as of yet...so... 》
My way of measuring consumption is 》Wh/altitude gain《 IMO the only realistic measure of efficiency. From my own testing these are the main factors having some significant effect on range in the following order from higher to lower:
1. (Rider+Bike) Weight
2. Terrain average incline
3. Assistance level and drive force settings
4. Trail conditions
5. Tire pressure (1,5 Psi/0,1 Bar less pressure= to cca 1 Wh/100m altitude higher consumption).
6. Suspension setup
7. Colder conditions(Under 10°C Average)
You wrote about my mentioned 1900m climb number being of no value as such, yes you are right, so Ok we can talk full numbers and also just for perspective, I live under a 1250m high hill/mountain, so here is a description of a double climb in one go with all the stats...》》》》
Rider + Bike Weight = 116kg(90+26)
Wheelset = Mullet(27,5 rear not optimal for best efficiency)
Battery = 800Wh
Terrain = asphalt, forest paths, dry, loam, rocky, tree routes, loose - basically a full mix
Average Assist level = 250%(2/3 of Max)
Torque = 85Nm
Launch Setting = 4 out of 7
Average temperature = 24°C
Average moving speed = 18,4 kmh
Tire Pressure = 1,7 bar (EXO+ 2,5; DD 2,4) WT
My power input = 165W(normalized power)
Average terrain incline = 8,3%
Distance traveled = 65,4 km
Actual climb distance = 11,3 km x (2)
Altitude gain = 1875m
Battery consumption = 95% = 762Wh
Average consumption = 40,6Wh/100m altitude gain
Well these are the stats, leaving them here, everyone can judge for themselves...
Additional for anyone interested I am also attaching a graphic presentation(my own online research) of how system(rider+bike) weight with slope incline affects driving force(Nm).
The number you see in the graph is how much motor torque you loose with weight and slope incline,
I. E. if your system weight is 113kg at an incline of 10% you loose 33,8Nm of avaliable motor torque and so on...
This could be useful, say for someone deciding between a full fat or an SL ebike.
Cheers
️
Randy
Member
The whole range conversation seems to me a bit unnecessary. In the end, the actual efficiency differences from motor to Motor are minute so range is dictated by more significant factors. So its battery size less, bike tyre efficiency, trail conditions and then, importantly, how much assist you have set it up to run at.
I too am far more interested in efficiency (range) than peak power. With this in mind, it would be great if one of these bike testers did all their tests with a powermeter rear hub. This would allow a simple absolute percentage efficiency that was reasonably accurate.
I am sure that for every motor absolute efficiency will be different between modes but if brand A is 75% efficient in it's most efficient mode and brand B is 60% then that would be a useful guide. It might also be that a motor tuned to be most efficient at low power is a better choice for a particular consumer than one tuned to be most efficient in boost even though the headline number might be lower.
Incidentally 1200W at 36v is 33 Amps which is a hell of a lot.
I also find it strange that the EMTB test guy kept comparing it to the CX motor without mentioning the SX motor.
I am sure that for every motor absolute efficiency will be different between modes but if brand A is 75% efficient in it's most efficient mode and brand B is 60% then that would be a useful guide. It might also be that a motor tuned to be most efficient at low power is a better choice for a particular consumer than one tuned to be most efficient in boost even though the headline number might be lower.
Incidentally 1200W at 36v is 33 Amps which is a hell of a lot.
I also find it strange that the EMTB test guy kept comparing it to the CX motor without mentioning the SX motor.
Rando_12345
Active member
I used to think that, but have changed my mind now, some motors do heat up a lot more than others and are quite a bit more inefficient than others, at least at max assistance.
For e.g. my Yamaha based Giant does 1600m climbing in max assistance with an 800Wh battery, whereas my riding group will do the same loop with me on their 700-720Wh Bosch and Brose systems, with noticibly more assistance usage from them (i.e. a 400% assist Bosch and Brose pull harder than a 400% assist Yamaha). Similar weights, bikes etc. So there can be a 10-15% difference in range for the same battery capacity.
That said I do believe Bosch, Brose and Shimano are quite similar in efficiency, so it is reasonable to believe the DJI is around the same. But, considering the DJI maxes out so much higher in torque and wattage, I would be optimistic that it is much cooler than the others when tuned to similar assistance as a maxed out Bosch.
Randy
Member
Thats proper 'thumb in the air' stuff though. My range can vary 10% day to day on the same bike, depending on how tired I am, and it only takes small adjustments to the support strategy to make big changes in range. It would be interesting to do the maths...
If manufacturers would include graphic presentation like this, that would be the best...here you can see a clear relationship between torque, power and cadence. Looking forward for first lab tests of the Avinox. That will tell the real picture how the motor behaves.
Orange lines is torque, blue lines is power.
You can see here that Bosch can maintain high torque up to 70rpm, Sram has a higher torque as of begin up to 55rpm then drops to Bosch levels at 70rpm, the Giant's torque starts at lower levels than both other and starts dropping further at 60rpm.
As you can see, higher the cadence > lower the torque > higher the power > higher power > higher consumption. If you can create a motor that can maintain a wide high torque/cadence window you have a winner. Interestingly the Spesh guys mentioned in their interview they also focused on the cadence/torque relationship in the development of new upcoming bikes...
Sram Eagle/Brose
Bosch Performance CX
Giant Syncdrive Pro MG
Orange lines is torque, blue lines is power.
You can see here that Bosch can maintain high torque up to 70rpm, Sram has a higher torque as of begin up to 55rpm then drops to Bosch levels at 70rpm, the Giant's torque starts at lower levels than both other and starts dropping further at 60rpm.
As you can see, higher the cadence > lower the torque > higher the power > higher power > higher consumption. If you can create a motor that can maintain a wide high torque/cadence window you have a winner. Interestingly the Spesh guys mentioned in their interview they also focused on the cadence/torque relationship in the development of new upcoming bikes...
Sram Eagle/Brose
Bosch Performance CX
Giant Syncdrive Pro MG
The only meaningfull range figure is how much battery is used by a specific rider on a specific bike riding that rider's typical local trails in typical weather conditions!! I have never understood why folk describe range in terms of climb! I ride very often 2 forest areas. Both consist a sequence up single track downs and then climbs back up. The climbs back up are probably the same gradient on average in each forest but in one forest they are gravel tracks/fireroads, whilst in the other they are very sandy. I can think of another location where a lot of the climbing is very steep and technical. No way you will get the same battery consumption in each location.
And what about a cross country type ride which is mostly flat? We all know the large list of variables such as rider weight, suspension platform, tyre weight and varying rolling resistance, gear use/cadence, power mode used, trail conditions etc............some are rarely mentioned however, such as wind resistance and rider skill ( maintaining momentum/using natural trail features to accelerate the bike etc).
About all that can be said is that the same rider/bike/motor combo should expect to get more range if fitted with a 750w/h battery as opposed to a 625 w/h battery.............even then any increase in range is unlikely to be exactly proportionate to increase in battery capacity.
Lost cause!!
And what about a cross country type ride which is mostly flat? We all know the large list of variables such as rider weight, suspension platform, tyre weight and varying rolling resistance, gear use/cadence, power mode used, trail conditions etc............some are rarely mentioned however, such as wind resistance and rider skill ( maintaining momentum/using natural trail features to accelerate the bike etc).
About all that can be said is that the same rider/bike/motor combo should expect to get more range if fitted with a 750w/h battery as opposed to a 625 w/h battery.............even then any increase in range is unlikely to be exactly proportionate to increase in battery capacity.
Lost cause!!
Rando_12345
Active member
New Nicolai with Pinion gearbox announced for various motor efficiencies from a cargo bike test.
I guess it depends where you live, but here in southern France the weather is mostly dry, we don't bother riding when it's wet, temperature between 10-30 most of the year, riding big mountains, the range in terms of climbing is very consistent for a given rider using turbo (around 2m/Wh). I've recorded hundreds of strava rides, compared battery percentages with friends during rides and made a couple excel sheets, it's a bit more than anecdotal but still very much only applies to my region and the riding here.
Let's just continue our ramblings until Rob posts his ride review!
Now we want an MGU vs DJI face off Rob! Tell us which is the new generation for ebikes!
I guess it depends where you live, but here in southern France the weather is mostly dry, we don't bother riding when it's wet, temperature between 10-30 most of the year, riding big mountains, the range in terms of climbing is very consistent for a given rider using turbo (around 2m/Wh). I've recorded hundreds of strava rides, compared battery percentages with friends during rides and made a couple excel sheets, it's a bit more than anecdotal but still very much only applies to my region and the riding here.
Let's just continue our ramblings until Rob posts his ride review!
Now we want an MGU vs DJI face off Rob! Tell us which is the new generation for ebikes!
I’m waiting for one more motor to be released
Rando_12345
Active member
See you on the 30th
Peaky Rider
E*POWAH Master
Not sure I dare ask this question and it may already have been asked in any case but, any news on de-restricting?
Unlikely, margin over a frame is relatively small compared to a whole bike.
nrgbod
Member
Does anyone know if the pro carbon bars have Stealth Routing: Wire ports & grooves under the grips like the OneUp carbon E bars have?
I want to fit a Zirbel shifter linked to an axs board hidden inside the bars.
I want to fit a Zirbel shifter linked to an axs board hidden inside the bars.
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I‘m wondering ig i am the only person who is missing an bashguard.
Yes I know it’s a trail/AM-Bike but riding e.g in Finale Ligure or Dolomites some kind of chainring protection would be nice.
The only possibility I see is mounting a Bashring on top of the spider.
On the picture you cannot recognize if it is possible and I’m waiting for some answer of Amflow. But with the experience of the last answers I’m not very confident in a technical answer.
So @Rob Rides EMTB as I understand you already has the bike at home. What is your estimation? Will a bashring fit (clearance to cranks, flat surface of the outside of the spider etc.)
Maybe you or someone else has another solution?
Yes I know it’s a trail/AM-Bike but riding e.g in Finale Ligure or Dolomites some kind of chainring protection would be nice.
The only possibility I see is mounting a Bashring on top of the spider.
On the picture you cannot recognize if it is possible and I’m waiting for some answer of Amflow. But with the experience of the last answers I’m not very confident in a technical answer.
So @Rob Rides EMTB as I understand you already has the bike at home. What is your estimation? Will a bashring fit (clearance to cranks, flat surface of the outside of the spider etc.)
Maybe you or someone else has another solution?
Rando_12345
Active member
On the one hand the range he got from the bike was weak enough (1000m up, 35km with 20% left), but on the other hand, I checked his strava to confirm the above stats, dude picked up half the KOMs in the area both up and down, good sign!
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On embn there was also something a sponsored video as you can see.
Just be mindful from _mbn, nearly all they do - as tons of channels - are explicitly or not sponsored.
I am really eager to see mid-long term reviews from normal people, we are mostly not as good as Neil who's a former pro, so maybe needing more watt (from leg, line choice, etc) for the same result!. We need also to see how the motor will perform after a season, like in uk full of rain and mud.
NB: careful about strava, pretty easy for anyone to tweak data, not saying they did it at all, just something to have in mind.
zerofunds
Member
I don't know what the obsession is with range, if you can't get enough cycling in with an 800w battery then maybe go back to an analog rig, or ride harder in turbo. I don't think ebikes are a good fit for people who like to grind out a whole day in eco.
Confused . . if you can't get far enough on a given battery you're going to be riding a much shorter distance on an analog bike or by riding an ebike in turbo.
My eMTB in 'eco' is a perfect fit for a day out riding ~50k on single tracks over 6hrs, with a bit of 'trail' towards the end, leaving <10% battery. Anything else would mean a much shorter ride and much less fun.
I also think that people do not understand people are riding different stuff on emtb.
For example as a chairlift, I need tons of power for huge uphills I have (ones I would do by pushing the bike) and really nothing for the rest. For people doing more mellow stuff they would have more `range`, more miles/km than me definitely.
Everything is a perpective.
DirkWisely
New Member
Is Amflow not selling mostly direct?
I was under the impression not.
E-bikes though really do need some support. If DJI/ Amflow provides online diagnostic software, quick shipment of warranty parts with good online support, availability of all parts at reasonable costs after warranty, etc. I'd consider an Amflow. But that's yet to be seen and a heck of an initial risk.
xtraman122
Member
I can’t believe they’re allowing these to be sold direct on Alibaba, that’s bizarre.
Let's add the VAT and customs rights?
Nothing less than 20% for taxes and customs I have no clue but it will be spotted as it holds electronics and is big!
Rando_12345
Active member
If you can dodge the tax, and get the bike months/years earlier than the official release depending on your country then maybe. But that's an expensive gamble alright...
Think of all the uphill KOMs that you could have unchallenged in France...
Think of all the uphill KOMs that you could have unchallenged in France...
How much elevation?
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