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

Curious about M820 motor noise too!
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To me the noise levels are very worrisome.

What can be done to mitigate it?
After market nylon gear?
Worth re-greasing like the larger older motors?
Could sound proofing squeezed in the frame possibly do any difference?
 
TCFlowClyde said:
Rocky boost mode?

Noise during climbs and turbo modes?

Thanks in advance.💪
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Noise is perceivable but nothing really disturbing for me, but not a TQ motor for sure. In turbo mode its a lil loud.

I've no idea how to enable rocky boost mode, and I have the DP E180 controller so it should enable it
 
stuff said:
just checked and I still have 2 leds left, so probably a 50km route with 1300m can be easily done, enough for me
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wow, impressive for a small battery like this! Very excited to get the bike (LCE930 for me)
 
TCFlowClyde said:
Curious about M820 motor noise too!
View attachment 114807
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Forestal told me by e-mail that their motor is unique to them and is not just an M820. I would have preferred it to just be an M820 so that rebuilds, and replacements were available for many years. Truth is that Forestal is much more likely to shut the doors rather than Bafang.

Is the Forestal motor the same architecture, but with different mounts? Is the exact same motor but with Ti shafts, etc. I don't know?

As far as the noise goes, well the new Levo SL uses a honeycomb structure on the new casing. Some insulation might be the best path forward.

I will admit that reports of high noise were the primary reason I blew off purchasing a Forestal frame set, which they are selling now at reasonable prices.
 
Suns_PSD said:
Forestal told me by e-mail that their motor is unique to them and is not just an M820. I would have preferred it to just be an M820 so that rebuilds, and replacements were available for many years. Truth is that Forestal is much more likely to shut the doors rather than Bafang.

Is the Forestal motor the same architecture, but with different mounts? Is the exact same motor but with Ti shafts, etc. I don't know?

As far as the noise goes, well the new Levo SL uses a honeycomb structure on the new casing. Some insulation might be the best path forward.

I will admit that reports of high noise were the primary reason I blew off purchasing a Forestal frame set, which they are selling now at reasonable prices.
Click to expand...

Noise like a soft whine or whirring sound, especially in turbo/boost mode for me isn't a big deal and fairly normal for most full-powered motors...I just don't want a metallic grind or high pitch shreek from a banshee or gremlin banging on a metal pipe!😁

This was reported by one YouTube influencers from Norway on his EMTB Videos channel last year on the Cyron review. Maybe his factory demo ride was haunted by robot-ghosts?🤖👻

So, maybe that issue was attenuated somewhat since then by Forestal/Bafang.🤞 Perhaps, the higher torque and power of M820-75Nm somehow mitigates the noise in this motor.🤞🤞🤞

From the three that have their CEF50 build up-and-running from their preliminary reports, it may be more quiet than the Forestal EonDrive60/Bafang M820-60.👍

My reasoning, if the noise were really too loud or irritating, it would standout as noteworthy. So far, it's the impressive power that shines! 😎

Which is what most want to hear! Sounds like the M820-75Nm is measuring up to many expectations!💪

My build should be going up in the next few days if all goes well. Today is the shipment delivery day by FedEx. So hopefully, it gets to my door trouble-free!😇
 
Maybe someone could, hint hint Tom, weight the standard Bafang cranks to help determine how much can be saved buying carbon cranks. The weight and the price of the Miranda is very tempting.
ALso the offsets like in the drawing above to determine which set of cranks to get.
 
for @stuff
Another great feature of the M820 is the boost function called “Rocky”. Activating this function is simple, with a single or double click on the “+” sign, dependent on if you already in the boost mode. When entering the “Rocky mode” (seen in the display as a special Rocky icon) the rider will enjoy a “Rocky push feeling” for a set continuous period.
 
mike_kelly said:
Maybe someone could, hint hint Tom, weight the standard Bafang cranks to help determine how much can be saved buying carbon cranks. The weight and the price of the Miranda is very tempting.
ALso the offsets like in the drawing above to determine which set of cranks to get.
Click to expand...
I think somebody weighed 'em already that had a M820 motor....cast alloy 170 mm at 460-480g ish. It's posted over at the M820 thread.

Eventually, I'll weigh them but low priority for now. Much higher priority is my MegMeg fitment and travel clearance.💪
 
mike_kelly said:
Even 460-288=172 nearly 6 ounces savings.
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Well maybe it was more 400+ g. It's on that thread about 2 months ago. You should be able to find it.

It's been so long, I can't even remember how much my 155 mm purple Hope Cranks are anymore. Months since I weighed those too?😝
 
The weight Karokonig reported was 498g!
Your weight on the Hope is 465g.
498-288=210 or 13 ounces savings with the MIranda. But not sure what the Q factor would be 8 or 16? Not sure how that specification is measured
 
Filipe at Maranda seemed to think that the Bafang M820 would require their Q16 cranks. I am not sure what the Q rating they use means. I have always dealt with simply the measurement of the arms installed in the frame. So I am not sure what they mean by Q8 vs Q16. The FB clearly means and increase in offset. Anybody run across this nomenclature before?
I would buy those Q8 Carbon cranks if they would fit the chainline.
 
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The Q factor is the distance between the right and left crankarm at the bore for the pedal axle at the inner faces of the cranks.. Only problem could be, that the „lower Q“ crank hits the chainstay on left or right side. The chainline of both cranks is the same, the chainring spider is mouted to the motor axle, not to the crankarm!
 
Thats right. It is why I was confused at what Q8 or Q16 means. Maybe their in-house nomenclature. I have not heard it anywhere else. Maybe we can get a certain person who is about to get his bike to make measurements of the Bafang crank to compare to Miranda's diagram. I would like to save 13 ounces. That could make the difference in an under 40lbs bike.
I hope he is busy unboxing his frame.
 
mike_kelly said:
The weight Karokonig reported was 498g!
Your weight on the Hope is 465g.
498-288=210 or 13 ounces savings with the MIranda. But not sure what the Q factor would be 8 or 16? Not sure how that specification is measured
Click to expand...

He also measured the Miranda Carbon 165mm standard (not FB) at 312.4g
Also measured 12mm wider inside crank - inside crank, at the pedals.
This means more chainstay clearance than the standard Bafang. No need for FB version I would think.
If you went with FB, it will be 15mm wider than oem.

Karokonig post

He went on to say the cranks work no problem
 
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spokemon said:
He also measured the Miranda Carbon 165mm standard (not FB) at 312.4g
Also measured 12mm wider inside crank - inside crank, at the pedals.
This means more chainstay clearance than the standard Bafang. No need for FB version I would think.
If you went with FB, it will be 15mm wider than oem.

Karokonig post

He went on to say the cranks work no problem
Click to expand...
The only problem is that MIranda makes a lot of cranks so it depends which one he was measuring. I think the Q8 and Q16 are different and the previous diagram is the Q8. What was the crank Karokonig comparing?
 
spokemon said:
He also measured the Miranda Carbon 165mm standard (not FB) at 312.4g
Also measured 12mm wider inside crank - inside crank, at the pedals.
This means more chainstay clearance than the standard Bafang. No need for FB version I would think.
If you went with FB, it will be 15mm wider than oem.

Karokonig post

He went on to say the cranks work no problem
Click to expand...
OEM is not on sale. I had to buy FB.
 
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