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

LJH · Apr 13, 2024

TCFlowClyde said:
Permission granted by @LEE. to show off his large frame w/big 36 forks/720Wh build.

Clean and white sleek in color 20.46 kg/45.11 lbs. It's the wet weight with sealant and pedals and loaded with premium componentry, so it won't get too much lighter!

Well done!

He's still working out headset issues, so he's not able to ride review it yet. He'll post updates when he's able. Others are likely doing a shakedown ride as I write, and will likely chime in when they're ready too hopefully!

Mine is still a week away or so!

Again, great build @LEE.! View attachment 113285 View attachment 113286

Who is producing this frame? Can you buy directly from production plant or do you need to buy fron

LAnton said:
The weight of the empty case is 1kg. I think that light models of well-known brands with non-removable batteries do not have such a heavy case. The frame itself is a strong case for the battery.

Who produces the CEF50 frame? Can you buy directly from the factory?

TCFlowClyde · Apr 13, 2024

LJH said:
Who is producing this frame? Can you buy directly from production plant or do you need to buy fron

Who produces the CEF50 frame? Can you buy directly from the factory?

SZZS is the frame manufacturer. Can buy it directly from them via Alibaba.com.

Jean seems most knowledgeable over others. Just tell her you're interested in the CEF50.

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un..inc · Apr 13, 2024

ficorama said:
hello everyone. I removed all unnecessary things from the bike. under 21kg, ready to drive, DIY 700wh battery.

View attachment 138227

What are unnecessary Things?
Impressive weight for a big battery!

ficorama · Apr 13, 2024

un..inc said:
What are unnecessary Things?
Impressive weight for a big battery!

steerer tool, co2 cartridge in the steerer and in place of the button, bottle cage

Myalteregohamish · Apr 13, 2024

92se-r said:
Does it do it with lower assist levels or only boost?

It seemed the more I demanded of the bike the more I noticed, what I would describe as a momentary disruption of power delivery.

borysgo2 · Apr 14, 2024

Hi.
I am going to go ahead and try CEF50 frame. Gathered some information but there are some stuff I am not sure about.

1. From October 2023 supposed to be new front triangle available to accommodate coil shock. The question is how to recognise it ?
Is this a frame with 2024 and UDH hanger in description ? Or just ask someone there to make sure new type of frame is supplied.

2. Another info I tried to get is max front chainring, but I think found the answer, someone is running 38T so all good. Anyone else running 38T ?

3. What is diameter of the supplied 720Wh round battery ?

Any info more than welcome.
Regards

Herculesridesebikes · Apr 14, 2024

ficorama said:
Hello everyone. the bike is assembled, some other small things, then on to the real ride.
I did a firmware update. firmware CRX30PC3615E102003.3 works for me. and with CRX30PC3615E102003.2 it doesn't recognize my battery.

first impressions, the engine has a lot of power. only in B mode, after sudden pedaling, the engine shuts off, then starts again after a few meters. and when it rotates constantly, everything is ok, only when the pedal is pressed hard, the assistance turns off.

the weight is about 20.5 kg, I'm adding some other little things, so I hope it won't be heavier than 21 kg.

Frame XL
battery DIY 11s3p 21700 lg 5800mah cells.
fork Zeb 29 select 170mm
Shock suntour triair 210x55 with offset bushing. ete length with the offset bushing is 214mm, so I left the stroke 55mm.
Wheelset Mavic e-deemax mullet s30-s35
Tires prowall casing
front pirelli scorpion enduro s 29x2.4
rear in arrival pirelli scorpion enduro s 27.5x2.4
Cassette 12 spd. 11-52 aliexpress
Shifting Sram gx
brakes Hayes dominion a4, 220mm rotor

View attachment 137822 View attachment 137823 View attachment 137824 View attachment 137826 View attachment 137827

Are you running you offset bushings in reverse? I tried this but found they would eventually spin back around after some riding.

ficorama · Apr 14, 2024

Herculesridesebikes said:
Are you running you offset bushings in reverse? I tried this but found they would eventually spin back around after some riding.

I mounted the bushings to extend the length of the shock. now the installed length is approx. 214-215mm. they don't turn to me, when you squeeze them so they stay in the position they need.

ficorama · Apr 14, 2024

Myalteregohamish said:
It seemed the more I demanded of the bike the more I noticed, what I would describe as a momentary disruption of power delivery.

Hello. I started having interruptions in my pedaling today. I noticed that it doesn't show the speed correctly. for example, I'm driving 24 km/h, then it shows 13, then 8, then 24, and it keeps changing speed. and it threw error 21, speed sensor, a couple of times. I think the problem is the bad position of the speed sensor, it's a little too far from the magnet. I will try a DIY magnet. which magnet are you using?

Myalteregohamish · Apr 15, 2024

ficorama said:
Hello. I started having interruptions in my pedaling today. I noticed that it doesn't show the speed correctly. for example, I'm driving 24 km/h, then it shows 13, then 8, then 24, and it keeps changing speed. and it threw error 21, speed sensor, a couple of times. I think the problem is the bad position of the speed sensor, it's a little too far from the magnet. I will try a DIY magnet. which magnet are you using?

No speed sensor related issues, or errors on the display. The whole thing dead. I recorded a video and sent it to Lynda. We’ll see what bafang says about it.

calvintys · Apr 15, 2024

ficorama said:
Hello. I started having interruptions in my pedaling today. I noticed that it doesn't show the speed correctly. for example, I'm driving 24 km/h, then it shows 13, then 8, then 24, and it keeps changing speed. and it threw error 21, speed sensor, a couple of times. I think the problem is the bad position of the speed sensor, it's a little too far from the magnet. I will try a DIY magnet. which magnet are you using?

i am using this , no problem only once when my sensor screw not tighten enough n it out of position.

0.81￡ 87% OFF|2022 Motorcycle Speedo Odometer Rotor Magnet For 125 200 250 300 350 450 500 530 EXC XC XCW XCF XCFW EXCF TPi Six Days 2003 2023| | - AliExpress

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ficorama · Apr 15, 2024

Myalteregohamish said:
No speed sensor related issues, or errors on the display. The whole thing dead. I recorded a video and sent it to Lynda. We’ll see what bafang says about it.

does not work! disaster. what firmware did you use?

ficorama · Apr 15, 2024

calvintys said:
i am using this , no problem only once when my sensor screw not tighten enough n it out of position.

0.81￡ 87% OFF|2022 Motorcycle Speedo Odometer Rotor Magnet For 125 200 250 300 350 450 500 530 EXC XC XCW XCF XCFW EXCF TPi Six Days 2003 2023| | - AliExpress

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my problem is that the magnet barely passes over the sensor. they drilled the holes for the sensor wrong. I will try to move the sensor or magnet a little by 3-5 mm. yesterday it showed me error 21 20 times. and the firmware needs to be changed. Linda sent me the e road firmware, because I reported to her that in Boost mode, the engine stops and it shows me the error 09.

calvintys · Apr 15, 2024

the stock magnet might has gap problem.

ficorama · Apr 15, 2024

here is the firmware i got from linda

voigtkampff · Apr 15, 2024

ficorama said:
my problem is that the magnet barely passes over the sensor. they drilled the holes for the sensor wrong. I will try to move the sensor or magnet a little by 3-5 mm. yesterday it showed me error 21 20 times. and the firmware needs to be changed. Linda sent me the e road firmware, because I reported to her that in Boost mode, the engine stops and it shows me the error 09.

have a look at my solution to the sensor position issue in this post SZZS specific CEF50-main thread (initial builds and troubleshooting related only) (strong neodymium magnet glued to the rotor at proper place). The magnet is 8x3-3 variant from this offer 1.79￡ 3% OFF|2 50 pcs Strong Magnets Countersunk Round NdFeB Powerful Rare Earth Permanent Neodymium Magnet Fridge Magnets for DIY| | - AliExpress

Yozha · Apr 15, 2024

Hi guys.
Has anyone weighed the frame+engine+cranks+battery 700wh 48wt kit (all the kit that comes with the frame)?
I want to pre-calculate the weight of my build
.

calvintys · Apr 15, 2024

Yozha said:
Hi guys.
Has anyone weighed the frame+engine+cranks+battery 700wh 48wt kit (all the kit that comes with the frame)?
I want to pre-calculate the weight of my build
.

SZZS Frame has 2 different carbon , t700 n t800...weight difference 200 gram

92se-r · Apr 15, 2024

voigtkampff said:
my investigation into battery level indicator jumping by large values continues... I see the contacts of battery XT30 connector are covered by some kind of dark patina. They are supposed to be gold plated so I don't quite understand why this happens but who knows, maybe they are the culprit. The question remains, how to safely clean them when I can't just disconnect this cable from the battery, which must remain charged to 40+ volts at all times? And how to ensure they won't "rust" again?

Most likely a bad solder joint causing excessive heat. I would cut it off and put another on. So this is as i suspected, a high resistance connection.

92se-r · Apr 15, 2024

Myalteregohamish said:
It seemed the more I demanded of the bike the more I noticed, what I would describe as a momentary disruption of power delivery.

This does seem like a thermal issue. I wonder if gap pad has been compromised.

voigtkampff · Apr 15, 2024

92se-r said:
Most likely a bad solder joint causing excessive heat. I would cut it off and put another on. So this is as i suspected, a high resistance connection.

At this moment I'm under the impression that this might not be a battery issue but rather some metering problem. Anyway, I ordered a bluetooth coulometer to monitor the voltage & current as I ride and I will try recording a movie with the exact moment SoC is jumping on HMI, what are the exact voltage, current and power draw readings when this happens. This will be useful for eventual warranty claims with SZZT. Investigation continues...

The coulometer in question is 24.6￡ 4% OFF|BL140F DC 10 100V 0 400A Battery Tester Coulomb Counter Meter Capacity Indicator Ammeter Voltmeter Bluetooth Battery Monitor| | - AliExpress

ficorama · Apr 15, 2024

ficorama said:
here is the firmware i got from linda

Hello. today I played a little with the magnet, however it interrupted the assistance in B again. after that I installed this firmware and everything is ok. I drove a few km uphill and it didn't stop. although it is e-road firmware, it seems to me that it is not less powerful than before. does not have such a strong overrun. for the moment as far as I could see the max power, it showed 540-550W on the screen

Screenshot_20240415_183145_Samsung Internet.jpg

92se-r · Apr 15, 2024

voigtkampff said:
At this moment I'm under the impression that this might not be a battery issue but rather some metering problem. Anyway, I ordered a bluetooth coulometer to monitor the voltage & current as I ride and I will try recording a movie with the exact moment SoC is jumping on HMI, what are the exact voltage, current and power draw readings when this happens. This will be useful for eventual warranty claims with SZZT. Investigation continues...

The coulometer in question is 24.6￡ 4% OFF|BL140F DC 10 100V 0 400A Battery Tester Coulomb Counter Meter Capacity Indicator Ammeter Voltmeter Bluetooth Battery Monitor| | - AliExpress

Its not a metering issue, the discoloration of the connector means you overheated that connector. Most likely a cold solder joint. Once you compromise that connector it will just get worse and worse and pretty soon you wont be able to ride at all because it will undervoltage as soon as you draw any current. It is a pretty obvious smoking gun when the contacts are discolored.

Myalteregohamish · Apr 15, 2024

CarolinaCrawler said:
This sounds intriguing. What frame is this?

I posted a review here.

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MrFixit · Apr 15, 2024

Thanks TCFlowClyde for starting this thread. I built my CEF50 last year as I wanted something lighter than my E10. I just want to share with those who ride in wet weather (or who uses a hose pipe to wash their bike) something I recently discovered, water builds up inside the rear top yoke (as marked in the photo). I discovered it recently when I tipped the frame forward about 45deg when doing some maintenance work on a stand.

TCFlowClyde · Apr 15, 2024

MrFixit said:
Thanks TCFlowClyde for starting this thread. I built my CEF50 last year as I wanted something lighter than my E10. I just want to share with those who ride in wet weather (or who uses a hose pipe to wash their bike) something I recently discovered, water builds up inside the rear top yoke (as marked in the photo). I discovered it recently when I tipped the frame forward about 45deg when doing some maintenance work on a stand. View attachment 138452

Yeah, I've had to invert (wheelie) off the stand to dump out extra water outta and stick a cloth in there to sponge any remaining. I usually wipe down with a wet cloth unless muddy (which is rare in my area.)

MrFixit · Apr 15, 2024

TCFlowClyde said:
Yeah, I've had to invert (wheelie) off the stand to dump out extra water outta and stick a cloth in there to sponge any remaining. I usually wipe down with a wet cloth unless muddy (which is rare in my area.)

I couldn't work out where the water was coming from when it happened

Yozha · Apr 15, 2024

calvintys said:
SZZS Frame has 2 different carbon , t700 n t800...weight difference 200 gram

Hm, Jean didn't say anything to me about that....

92se-r · Apr 15, 2024

Is there a hole in the link? Where does the water go in?

TCFlowClyde · Apr 15, 2024

92se-r said:
Is there a hole in the link? Where does the water go in?

No hole. Just pools up and or drips into the linkage potentially. I used Phil Woods water proof grease prior to putting the rocker arm back and to help reassemble easier to the tight fit. At least that's what I did to minimize water ingress.

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