SZZS specific CEF50-main thread (initial builds and troubleshooting related only)

TCFlowClyde

Active member
Feb 26, 2022
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866
Mesa, AZ
I’ve never had a Bafang motor and this would be my first diy. How is the drag on bafang motors?

Given the lighter weight without the battery, I’m wondering if it would be possible to run without the battery on park days. Def gonna have to remove it for traveling purposes.

Spoke with Linda and an extra battery is 280ish usd. Way too reasonably priced… almost wondering its gonna explode on me?
My Bafang M600s 43V and 48V motors act like an anchor with power off😲...like most full-powered rigs.

But for mid-powered classes, apparently, the EonDrive can be ridden with power off and doesn't seem to be too much more then Fazua60 and TQ50. Possibly, similar to the EP8 RS? I've ridden both, the former has a little drag and less with the latter. Maybe ask on the Siryon forum to rate gear friction for those that have ridden the other three?

I'm fully comfortable with the CEF50 in-house battery💪...I don't trust the Bafang BT-F014 as I have already outlined in previous threads.

The Bafang price for my 450Wh and 600 Wh batteries were $500 and $600 respectively and about $150-200 each for shipping during COVID times.🤯👹😞
 
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Waynemarlow

E*POWAH Master
Dec 6, 2019
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Bucks
My Bafang M600s 43V and 48V motors act like an anchor with power off😲...like most full-powered rigs.
I beg to disagree, my M600 motor almost totally disengages with no power ( that’s what the one clutch on the outer chainring bearings purpose is ) and I would just suspect it’s the fact you are having to pedal really hard to maintain any sort of comparable speed that you are blaming the motor.

Now on the other hand my mates Bosch Gen 4 will almost lock the motor into having to turn over the stator which should not happen, it’s been back to the dealer a couple of times but he’s being told it’s normal, mmmm.
 

TCFlowClyde

Active member
Feb 26, 2022
1,341
866
Mesa, AZ
I beg to disagree, my M600 motor almost totally disengages with no power ( that’s what the one clutch on the outer chainring bearings purpose is ) and I would just suspect it’s the fact you are having to pedal really hard to maintain any sort of comparable speed that you are blaming the motor.

Now on the other hand my mates Bosch Gen 4 will almost lock the motor into having to turn over the stator which should not happen, it’s been back to the dealer a couple of times but he’s being told it’s normal, mmmm.
No need to "beg'' to disagree.😉 It's just off topic for this thread.

The main question was related to Bafang motors and how well the CEF50--M820 specifically, can be ridden with no juice or w/o the battery in order to hit the bike park. So fundamentally, where is the drag on this motor likely compared to the other mid-powered motors? Especially related to the Fauza60 that is currently on Pivot Shuttle SL and Transition Relay (to be released soon). We were both very interested in the forthcoming Relay contrasts. And I just day demo'd the Shuttle SL recently (which I liked 😁). Prohibitive cost made me consider this build instead.💰

So, there is a little drag on the mid-powered motors overall but just some.... fortunately 😎. And much less than most full-powered rigs.

Personally, I really enjoyed the TQ50. That would be the motor most I would want to ride like an analogue bike. Probably, the Fazua60 second. From early reports from reputable YT reviewers, third would the RS/EonDrive.

Given the projected M820's beefy torque, and high PAS (which is what I want for 8-10 lbs less💪) and coming from a full-powered motor, that has very high "unpowered" drag, I'm hoping that it will be far closer to it's lower powered sibling on the drag/pedaling friction rating.🤞

Do you have any feedback on how the well the M820 motor disengages with no power directly compared to the RS, Fazua60, and or TQ50, and in particular to the EonDrive aka (M820--Posh)🤔?

For me personally, even while I plan on using the big 720 Wh battery on the CEF50 build, I'll want to DIY a little range extender or two if I can manage it. I hope NOT to go powerless if avoidable. But it would sure be nice to know I could reasonably pedal back to my vehicle with a very low drag motor, rather the have an "anchor" attached (M600🤯) to my effort that I've had to endure on the past. It all happened after taking a wrong turn, at night, with my riding lights fading, and swearing that this little climb back to my trailhead was blue-moderate, not chunky-black when I rode it on my analog bike the season prior...yikes.😞 And I was using my backpack spare smaller 450 Wh to make it home.

Fortunately, I made it back with maximal effort with the erie feeling that the phantom mt. lion "stalking" me in very dim light was "close".😁 The mental panic was great motivation to churn those merciless, high drag cranks to get to "safety" and to avoid future similar pedaling dilemmas.💪 The natural consequence was to raise my "range anxiety" awareness, which was already high as a heavier Clyde-rider.

I'm using the CEF50 build for more fitness attainment with agility gain and some stealth, so I might not range well...but knowing the 820-Beastie 75/95NM tune will be low drag would be an awesome benefit for money too!💸💰💎💵

Thoughts on the potential M820 motor drag? Or direct EonDrive comparison?🍻
 
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Suns_PSD

Active member
Jul 12, 2022
522
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Austin
The M820 is supposed to 100% decouple when not in use and Forestal owners have reported that it pedals exactly like a non-assist e-bike.

Here is another tidbit: I asked Linda to confrim the weight difference between the 410/ 710 battery was really only .7 kg. She stated that this was NOT correct and the weight difference is actually 1.5 kgs/ 3.3 #s. As rarely as I'd use the extra juice I'd stick with the 410 watt battery.

I'm either going to end up with the Relay, the new Levo SL, the Siryon or the CF50 by this summer. Just wish I could compare them all at this very moment and began fully moving forward.
 

TCFlowClyde

Active member
Feb 26, 2022
1,341
866
Mesa, AZ
The M820 is supposed to 100% decouple when not in use and Forestal owners have reported that it pedals exactly like a non-assist e-bike.

Here is another tidbit: I asked Linda to confrim the weight difference between the 410/ 710 battery was really only .7 kg. She stated that this was NOT correct and the weight difference is actually 1.5 kgs/ 3.3 #s. As rarely as I'd use the extra juice I'd stick with the 410 watt battery.

I'm either going to end up with the Relay, the new Levo SL, the Siryon or the CF50 by this summer. Just wish I could compare them all at this very moment and began fully moving forward.
Cool...but bummer too on weight difference for me. I'll plan my expectations for another lb added to my build.😜

But I'm glad you got to it first...was waiting for Linda to get back from Lunar NY to ask.👍.

On drag for the CEF50 we'll have to see... hopefully sooner rather than later.🤙

Excited on the CEF50 build potential but still maintaining reasonable expectations.🍻

P.S. I just made a request to Linda to maybe put the 720 Wh on a scale and take a pic to get an official measurement.

I'll post her response here either way to stem off future controversy.🙏
 
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TCFlowClyde

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Feb 26, 2022
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866
Mesa, AZ
The M820 is supposed to 100% decouple when not in use and Forestal owners have reported that it pedals exactly like a non-assist e-bike.
Just curious, how well does your Orbea Rise M50's (?) Shimano RS-motor decouple in comparison to analogue? 🤔

As an aside, I think I can test ride one this weekend (or soon) for a comparison...that and power performance. Want to see how much it predicts, as best as possible, the CEF50-M820 performance..
 

Zimmerframe

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Jun 12, 2019
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Brittany, France
I think everyone needs to keep in mind that most motor manufactures have been doing this for a few years now and have most of the "drag" issues ironed out with various de-coupling clutches.

Yes, the Bosch Gen2 still managed to have some resistance due to the gearing on the tiny chain ring spinning things up, but other than that there's pretty much zero resistance.

If you're not sure, just take the chain off and try turning the motor - there's nothing. If there is, it's faulty.

The problem is, with an assisted bike, you end up going faster and the assistance accommodates draggier tyres. For many riders when you hit 25kph, that feels like you hit a wall when assistance stops. Everyone suddenly thinks they're god and blames the motor, not the 25kg bike they're suddenly riding unassisted with tractor tyres on. Because we're all that super human that the motor wasn't really doing anything anyway ... :-D But now it's applying negative force and using all that energy to create enough heat to melt the frame or wirelessly transmit regen energy to the hoover dam by fed order 106.3-2.

If you're in the US, you have it worse, at 32kph it cuts - so it's a bit like a semi's driven into you. The amount of rolling resistance at 32kph on a 25kg bike is reasonably significant. If feels less so if you got there on your own with the motor off, but if the motor stops, it can feel like hell.

Some motors, like the Gen4 Bosch slowly ramp down assistance as you get near the limit, so the wall feels more like a few bricks and it's easier to ride over it - unless you're a low cadence rider, in which case it will just feel like you hit a rubber wall.
 

TCFlowClyde

Active member
Feb 26, 2022
1,341
866
Mesa, AZ
I think everyone needs to keep in mind that most motor manufactures have been doing this for a few years now and have most of the "drag" issues ironed out with various de-coupling clutches.

Yes, the Bosch Gen2 still managed to have some resistance due to the gearing on the tiny chain ring spinning things up, but other than that there's pretty much zero resistance.

If you're not sure, just take the chain off and try turning the motor - there's nothing. If there is, it's faulty.

The problem is, with an assisted bike, you end up going faster and the assistance accommodates draggier tyres. For many riders when you hit 25kph, that feels like you hit a wall when assistance stops. Everyone suddenly thinks they're god and blames the motor, not the 25kg bike they're suddenly riding unassisted with tractor tyres on. Because we're all that super human that the motor wasn't really doing anything anyway ... :-D But now it's applying negative force and using all that energy to create enough heat to melt the frame or wirelessly transmit regen energy to the hoover dam by fed order 106.3-2.

If you're in the US, you have it worse, at 32kph it cuts - so it's a bit like a semi's driven into you. The amount of rolling resistance at 32kph on a 25kg bike is reasonably significant. If feels less so if you got there on your own with the motor off, but if the motor stops, it can feel like hell.

Some motors, like the Gen4 Bosch slowly ramp down assistance as you get near the limit, so the wall feels more like a few bricks and it's easier to ride over it - unless you're a low cadence rider, in which case it will just feel like you hit a rubber wall.
So redirect here;😁 any feedback on the M820 or Eon/Drive specifically that you're aware of?
 

Zimmerframe

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Jun 12, 2019
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Brittany, France
So redirect here;😁 any feedback on the M820 or Eon/Drive specifically that you're aware of?
Haven't ridden either, but the general crowd from the M820 seem to give the impression of no drag. Obviously, the less powerful your motor, the less of a feeling there will be of "resistance" when it stops helping. Combine that with a lighter bike, which most people will be comparing it to and the natural conclusion will be "It's easier to pedal over the assistance"
 

TCFlowClyde

Active member
Feb 26, 2022
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866
Mesa, AZ
Haven't ridden either, but the general crowd from the M820 seem to give the impression of no drag. Obviously, the less powerful your motor, the less of a feeling there will be of "resistance" when it stops helping. Combine that with a lighter bike, which most people will be comparing it to and the natural conclusion will be "It's easier to pedal over the assistance"
💯. Makes sense.
 

Suns_PSD

Active member
Jul 12, 2022
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Austin
Just curious, how well does your Orbea Rise M50's (?) Shimano RS-motor decouple in comparison to analogue? 🤔

As an aside, I think I can test ride one this weekend (or soon) for a comparison...that and power performance. Want to see how much it predicts, as best as possible, the CEF50-M820 performance..

I don't have an Orbea Rise and don't yet own an e-bike.
 

TCFlowClyde

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Feb 26, 2022
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Mesa, AZ
The Rise has no power-off drag. Feels like an analog bike.
Subjective of course, but confirmed.👍 "Off power" has very, very low drag with Shimano RS. I just test rode the Rise H30 540 Wh. A little more turbo torque for climbing as well over the Fazua60 and definitely the TQ50.

Now if the EonDrive/Bafang M820-60 is as low drag and at least as powerful as the RS60, then the CEF50M820-75 should be very powerful indeed--even if Bafang is hyping it up the Nm a bit, 65-70Nm at the same motor weight should be the sweet spot for mid-powered, mid-weight, big travel E-enduro rig!

The CEF50 M820 410/720 Wh should be one bad-ass rig and totally economical DIY-build!!!🤙💸🍻
 

TCFlowClyde

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Feb 26, 2022
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Mesa, AZ
720 Wh battery is tentatively estimated at 3.8 Kg/8.37 lbs. But to be more definitive, I requested a scale-pic and is forthcoming...
Screenshot_20230206-094111.png
 

Suns_PSD

Active member
Jul 12, 2022
522
438
Austin
Bafang 410 Wh battery is quoted at 2.6 kg. So weight penalty is only 1.2 kg. This means 46% more weight, but 75% more capacity. Deal!

Seems you're making some assumptions. I have to assume that Linda knew the actual weights when she sent me the weight difference.

Still awaiting some details from Linda I requested about 2 weeks ago (during Lunar New Year).

For a moment I was ready to begin my purchase, but I've cooled a bit. Just want to get this decision correct.
 

TCFlowClyde

Active member
Feb 26, 2022
1,341
866
Mesa, AZ
I have to assume that Linda knew the actual weights when she sent me the weight difference.
Nobody is questioning you, just Linda and her weight estimate of the 720Wh.😁

Me personally, I'm just double checking Linda with a scale photo for her future accuracy. 😉

She's in sales with evolving product specs and might have been told varing numbers from the engineering department 😇
 

Kenk3589

Member
May 5, 2022
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40
Usa
Is the bike actually capable of taking a 55 mm stroke shock? How did someone calculate that? I’m worried I buy the shock and then it ends up buzzing the rear seat post.

Also, I’ve mostly seen 210x55 shocks being used on 130-140 mm travel bikes. Does this mean we need a progressive air shock with heavy tuning?
 

TCFlowClyde

Active member
Feb 26, 2022
1,341
866
Mesa, AZ
Is the bike actually capable of taking a 55 mm stroke shock? How did someone calculate that? I’m worried I buy the shock and then it ends up buzzing the rear seat post
We're only guessing on the kinematics from the previously posted progression curve....but I'll u know if I get seatpost rub or crack a seatstay.💪

My RS 210x 55 Sdlx w/NegMeg upgrade.
PXL_20230208_190724239.jpg
 

thaeber

Well-known member
Jan 26, 2021
887
769
Bruchsal, Germany
Is the bike actually capable of taking a 55 mm stroke shock? How did someone calculate that? I’m worried I buy the shock and then it ends up buzzing the rear seat post.

Also, I’ve mostly seen 210x55 shocks being used on 130-140 mm travel bikes. Does this mean we need a progressive air shock with heavy tuning?
Run mullet. I would bet my butt that this will work with the 55 stroke shock, there is no bridge between the seatstays that may hit the seattube 😊
 

Kenk3589

Member
May 5, 2022
61
40
Usa
Run mullet. I would bet my butt that this will work with the 55 stroke shock, there is no bridge between the seatstays that may hit the seattube 😊
I’m still confused on how a 55 stroke shock can get 162.5 mm travel. Most bikes using the 55 stroke shock has travel ranging from 140-150.
 

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