On the Bafang website there is no 720 wh battery compatible with the M820, maybe the battery with the round tube that they teach is the one that bafang announces as for EROAD, The anchors of these batteries are totally different as they are not removable and are designed to save weight, for a light ebike a 720 wh battery does not make much sense, it is very rare that bafang develops a 720wh battery with that concept. I think it is a frame manufacturer error.
SZZS specific CEF50-main thread (initial builds and troubleshooting related only)
- Thread starter TCFlowClyde
- Start date
thaeber
Well-known member
The 720 Wh is not a Bafang battery for my understanding. It’s a specific battery designed to fit into the CEF50 frame. The question is, if the battery supports CAN communication with the Bafang components. My E10 has a battery not supporting the CAN communication, so some details like charging cycles, battery health etc. cannot be read out. Not a big thing for me.
TCFlowClyde
Active member
- Thread starter
- #153
Nope, sorry see previous threads here. CEF50 manufacturer's is 720 Wh, in-house battery.
Also, one frame with two battery options Bafang 410, and the aforementioned that fit in the same downtube, using different cradle/hardware paired with each different battery.
I assume from the pics, the oversized downtube is likely really built for the larger in-house 720 Wh. But, for those wanting to shed another lb/kg, the 410 Wh. Probably a good option for lighter riders. This doesn't really appear to an issue/concern at this point. More will be revealed after Lunar New Year in early Feb.
Arguably, the 720 Wh may be better suited for the heavier riders, (or lighter riders with lots of elevation gain), and since no manufacturer range extender is offered. An aftermarket might be doable if a clever owner can successfully wire a little 250 Wh bottle battery extender as an example for the rest.
Plus, I'm unsure if the BT-F014 is truly 410 Watt hours of useable battery due to the reserve or complete shutdown being at 20-28%...very conservative , Bafang firmware, BMS protocol (like BT-F03 450Wh/BTF-04 650Wh batteries for my m600).
Lastly, the purported m820 higher 75Nmmax/95N may actually need the bigger battery to be practical for overall trail riding. The 720Wh may be a better option for many?IMHO
These variables kinda make this mid-powered, light-ish frame set unique, IF all Bafang marketing is accurate. We'll know as reports from the CEF50 get ridden a few rides after delivery in mid-March.
I'll make sure to chime in as 720Wh battery owner with my shake down review! Others with the 410Wh hopefully will do the same...for a nice comparison and contrast!
Either way, I think M820 CEF50 410Wh and 720Wh looks good on paper...hopefully the engineering is competent for both Bafang and Shenzhen Zhaosheng Carbon Fiber Technology Co.LTD (SZCFT)!
Bafang seems to have proven itself. And SZCFT makes both road/Mtn carbon frames...hopefully their venture into E-frames is solid too!!
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The photo shows that the bafang battery is different from the battery made by the factory. The factory can make at 420 or 710W 36V to choose from. So I ordered a 36V motor. I think we won't notice a difference between 36 and 42M. Self-assembly of an electric bike is a fun adventure. I think it's better not to buy a bafang for this frame, buy it from the frame manufacturer.
thaeber
Well-known member
Nothing to add!Nope, sorry see previous threads here. CEF50 manufacturer's is 720 Wh, in-house battery.
Also, one frame with two battery options Bafang 410, and the aforementioned that fit in the same downtube, using different cradle/hardware paired with each different battery.
I assume from the pics, the oversized downtube is likely really built for the larger in-house 720 Wh. But, for those want to shed another lb/kg, the 410 Wh. Probably a good option for lighter riders. This doesn't really appear to an issue/concern at this point. More will be revealed after Lunar New Year in early Feb.
Arguably, the 720 Wh may be better suited for the heavier riders, (or lighter riders with lots of elevation gain), and since no manufacturer range extender is offered. An aftermarket might be doable if a clever owner can successfully wire a little 250 Wh bottle battery extender as an example for the rest.
Plus, I'm unsure if the BT-F014 is truly 410 Watt hours of useable battery due to the reserve or complete shutdown being at 20-28%...very conservative , Bafang firmware, BMS protocol (like BT-F03 450Wh/BTF-04 650Wh batteries for my m600).
Lastly, the purported m820 higher 75Nmmax/95N may actually need the bigger battery to be practical for overall trail riding. The 720Wh may be a better option for many?IMHO
These variables kinda make this mid-powered, light-ish frame set unique, IF all Bafang marketing is accurate. We'll know as reports from the CEF50 get ridden a few rides after delivery in mid-March.
I'll make sure to chime in as 720Wh battery owner with my shake down review! Others with the 410Wh hopefully will do the same...for a nice comparison and contrast!
Either way, I think M820 CEF50 410Wh and 720Wh looks good on paper...hopefully the engineering is competent for both Bafang and Shenzhen Zhaosheg Carbon Fiber Technology Co.LTD (SZCFT)!
Bafang seems to have proven itself. And SZCFT makes both road/Mtn carbon frames...hopefully their venture into E-frames is solid too!!
Waynemarlow
E*POWAH Master
Only if you intend to recharge your battery in excess of 3K or more times. Tesla and others are advising this to get longevity of the battery, we on the other hand will be not interested in longevity but max Whs / weight.
1) anyone gotten the weights of the 410 vs. the 720 battery? The ~ 20% protection factor, would rule out the 410. However the 720 places lots of weight high and forward and although it might be 2kgs/ 4.4#s, it might be very noticeable while riding.
2) The BB drop is listed as 20mm, I presume that's actually -20mm?
3) I like a steeper STA and the other changes that come along with it as well, any problem running say a 215/55 shock (not even sure that exists actually)?
4) Someone posted that FSA makes some compatible -1 headsets, that would be a key component with a longer shock.
5) Generally Progression is measured from the sag point, which should be 30%, to 95% travel (at which point bumpers and crazy air ramp up dramatically change things anyways). I'm getting 22% progression, while pretty good (basically identical to my SJ Evo with a Cascade link) is not high for a 150mm travel bike. My SJ Evo still requires a massive amount of air can volume reduction to work well at similar numbers. I'd call it a minimum workable number if you ride aggressive. 25-30% is really where you want to be for a 150mm travel bike imo.
6) Knut in his review stated that the Eon Drive in the Forestal had a pretty unnatural power delivery and over run. I wonder if programming has been improved with the M820, or is it just the nature of the beast?
I did ride a Trek EXE today and in the low setting, it didn't pedal one bit better than my SJ Evo does due to the weight and the draggy tires it was running. Makes since as it's only about 50 watts in that setting. I think I want just a hair more for my e-bike. Sure I could turn the power up, but then I could see a rather rapid drop in battery juice (literally 4% in about 5 minutes in the mid setting and it wasn't even a climb).
Was fully intending to buy the cf Relay, however I like frame sets only and the idea of paying >$10K and then literally selling off every single part is really unappealing to me. Bet to even get the shock I'd want I'd have to spend >$13K. I'd have to deal with a bunch of idiots and probably be lucky to sell the parts for $1500 total.
There are great deals on Spesh SL e-bikes now, but I can't deal with the motor whine and plus a new one is being released.
So here I am.
2) The BB drop is listed as 20mm, I presume that's actually -20mm?
3) I like a steeper STA and the other changes that come along with it as well, any problem running say a 215/55 shock (not even sure that exists actually)?
4) Someone posted that FSA makes some compatible -1 headsets, that would be a key component with a longer shock.
5) Generally Progression is measured from the sag point, which should be 30%, to 95% travel (at which point bumpers and crazy air ramp up dramatically change things anyways). I'm getting 22% progression, while pretty good (basically identical to my SJ Evo with a Cascade link) is not high for a 150mm travel bike. My SJ Evo still requires a massive amount of air can volume reduction to work well at similar numbers. I'd call it a minimum workable number if you ride aggressive. 25-30% is really where you want to be for a 150mm travel bike imo.
6) Knut in his review stated that the Eon Drive in the Forestal had a pretty unnatural power delivery and over run. I wonder if programming has been improved with the M820, or is it just the nature of the beast?
I did ride a Trek EXE today and in the low setting, it didn't pedal one bit better than my SJ Evo does due to the weight and the draggy tires it was running. Makes since as it's only about 50 watts in that setting. I think I want just a hair more for my e-bike. Sure I could turn the power up, but then I could see a rather rapid drop in battery juice (literally 4% in about 5 minutes in the mid setting and it wasn't even a climb).
Was fully intending to buy the cf Relay, however I like frame sets only and the idea of paying >$10K and then literally selling off every single part is really unappealing to me. Bet to even get the shock I'd want I'd have to spend >$13K. I'd have to deal with a bunch of idiots and probably be lucky to sell the parts for $1500 total.
There are great deals on Spesh SL e-bikes now, but I can't deal with the motor whine and plus a new one is being released.
So here I am.
thaeber
Well-known member
720 Wh is 10S4P (40 pcs) of 21700 cells at 70g per cell. Means 2.8kg for the cells only. Plus appr. 500 g for the housing, BMS etc., so appr. 3,3 kg for the battery at minimum. The 410 Wh battery weight is given by Bafang, 2,6kg according to workbook 2023.
Welcome. Making a bike on a frame made in China is a very fun adventure. We must have patience and time.
I have read that the new battery of orbea rise 360wh is only 1.8kgs including the case.So the case should be around 300gr.And for the whole package cells,batteryholders and bms ,this should be around 1.5kg.
Anyone asked of they sell battery case only?
Also information about the weight?
Anyone asked of they sell battery case only?
Also information about the weight?
thaeber
Well-known member
360 Wh is 10S2P = 20 x 21700 cell @ 70 g each. 1.4kg for the cells, 0,4kg for the rest. Seams feasible..
thaeber
Well-known member
But this also means, bigger is better in regards of Wh to weight ratio of the overall battery.
here some pictures from emtbnews.de:
old battery:Der alte 360-Wh-Akku wog 2203 Gramm.
new one: Der neue 360er-Akku wiegt nur 1898 Gramm.
ok around 1.9kg!
old battery:Der alte 360-Wh-Akku wog 2203 Gramm.
new one: Der neue 360er-Akku wiegt nur 1898 Gramm.
ok around 1.9kg!
TCFlowClyde
Active member
- Thread starter
- #165
Just to highlight battery weight comparison.
3.3 kg big juice box (in-house)-
2.6 kg small juice box (Bafang)= 0.7 kg difference (+/- g) or 1.54 lbs
Makes sense!
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Yah, I would have to spring for the 720 for a 1.5# weight difference. Honestly though the weight difference was more like 5#s.
Forestal just started offering frame onlys, and they are coming out with the 'Performance' line without the computer which is going to remove further weight and money.
Not sure on the paint job, which while lovely looks expensive to do.
Forestal just started offering frame onlys, and they are coming out with the 'Performance' line without the computer which is going to remove further weight and money.
Not sure on the paint job, which while lovely looks expensive to do.
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TCFlowClyde
Active member
- Thread starter
- #168
I'm just guessing, but it looks like the Forestal tune of the M820 is at 60 Nm (EonDrive). Some are calling the "M820-Posh"
. And the Bafang tune at 75/95Nm aka "M820--Beastie" 
.
It seems that an Alibaba seller sells the CEF50 already assembled with different finishes. Shipping to Europe is $650.
m.alibaba.com
Source 2023 Carbon Fiber Super Light Bafang M820 36v 250w 720Wh Full Suspension Ebike eMTB on m.alibaba.com
2023 Carbon Fiber Super Light Bafang M820 36v 250w 720Wh Full Suspension Ebike eMTB, You can get more details about from mobile site on m.alibaba.com
m.alibaba.com
TCFlowClyde
Active member
- Thread starter
- #170
H
I don't know if that means anything but I'm sticking with the CEF50. Also, I noticed the shock size is bigger (230x65) on the trust as a few other build details like a traditional wired 12 spd transmission (so maybe it has frame cable ports...good idea IMO.).
Hmmm. I googled www.trust-bike.com and nothing came up.
I don't know if that means anything but I'm sticking with the CEF50. Also, I noticed the shock size is bigger (230x65) on the trust as a few other build details like a traditional wired 12 spd transmission (so maybe it has frame cable ports...good idea IMO.).
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temon10
Well-known member
Beware of chinese, they often write the wrong spec. Picture show rearshock 210 but they write 230 hahaahaha...H
Hmmm. I googled www.trust-bike.com and nothing came up.
I don't know if that means anything but I'm sticking with the CEF50. Also, I noticed the shock size is bigger (230x65) on the trust as a few other build details like a traditional wired 12 spd transmission (so maybe it has frame cable ports...good idea IMO.).
I can't tell from the photos, does the CEF50 use a Trunnion shock or no?
I'm curious if this frame can pull off a 230/ 57.5mm shock for a 15mm lower rear axle (enough for a Mullet) and 173mm rear travel.
Probably easier to just run some offset shock bushings, in reverse to lengthen the shock a few mm.
I'm curious if this frame can pull off a 230/ 57.5mm shock for a 15mm lower rear axle (enough for a Mullet) and 173mm rear travel.
Probably easier to just run some offset shock bushings, in reverse to lengthen the shock a few mm.
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TCFlowClyde
Active member
- Thread starter
- #174
Standard.... I hope.
I just bought standard e2e 210x55 recently. But it looks standard in pics...just hard to see. I have two trunnion E-mtbs.
temon10
Well-known member
210 is standart. trunnion 205.
You are absolutely right. I also made a lot of mistakes when buying. I advise you to buy only the frame motor and battery and nothing else. On Aliexpress, you can buy carbon parts separately from proven brands.
The CEF50 frame weighs 2500 g. The Dengfu E10 weighs more than 3500g of carbon fiber. The CEF 50 is a lightweight bike for easy tasks. Dengfu E10 for extreme skiing.
thaeber
Well-known member
We had that discussion earlier in this thread. If You want to overstroke the frame, recommendation would be a 216x63 shock. You can go Mullet on the rear and / or use offset bushings to finetune the geo. If You can use the full 63 mm stoke, You will get appr. 180+ mm rear travel.
thaeber
Well-known member
They still have the Vivid air or coil. Cane Creek still makes them. But You are right, this is a somewhat outdated, non-metric size not really common any more. Fox I didn’t check…
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