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

[Yozha]

When u popped it off did the original glue stay on the cup or the frame?

After pressing the cup out, there was a thin slightly sticky layer left on it and in the frame - I just applied fresh loctite.

 

[TCFlowClyde]

Check it out to see the Bafang motor parts breakdown.

My complements to Steve Jones from EMBN for fully embracing Bafang motor power, reliability, and inexpensive qualities.

My only minor dig....can they make a replacement casing gasket for the M820 before my 2,000 mile re-greasing.

 

[TCFlowClyde]

It may not be possible. Carbon fiber is a mild conductor and the frame may act as a shield block the bluetooth signal.

But, I wonder how DJI is doing it with their new drive system. I think the AMFLOW bike featuring DJI electronics has a carbon top tube integrated frame display connected to two handlebar remotes wirelessly via Bluetooth.

 

[voigtkampff]

But, I wonder how DJI is doing it with their new drive system. I think the AMFLOW bike featuring DJI electronics has a carbon top tube integrated frame display connected to two handlebar remotes wirelessly via Bluetooth.

probably they put BT antenna in the display so that it's not enclosed by the carbon on all sides. anyway, it's not like the carbon shell makes good quality faraday cage. first, graphite is not as good a conductor as metals, second, the fibers are sandwitched with resin which increases the insulation, third, the shell isn't grounded. I believe even in this thread there are folks who use BT comms to BMS hidden inside the downtube, so this doesn't look like a big issue. they could even glue film with microstrip antenna on the outside of the carbon shell close to handlebar to lower energy consumption by the controller

 

[TCFlowClyde]

probably they put BT antenna in the display so that it's not enclosed by the carbon on all sides. anyway, it's not like the carbon shell makes good quality faraday cage. first, graphite is not as good a conductor as metals, second, the fibers are sandwitched with resin which increases the insulation, third, the shell isn't grounded. I believe even in this thread there are folks who use BT comms to BMS hidden inside the downtube, so this doesn't look like a big issue. they could even glue film with microstrip antenna on the outside of the carbon shell close to handlebar to lower energy consumption by the controller

Alright then! Let's get Bafang engineering on it!

Maybe we can convince Steve at EMBN to cajole their engineers into going full wireless remotes. Plus, I think Forestal's Bafang display is wireless, so maybe resistance by Bafang?

 

[souftosouf]

1. There is no "canonical" way, there are some hacks documented in the forum
2. The engine provides 12V/0.5A via the light cable, so the choice is limited to lights < 6W. You can hack a circuit which will use the light cable to switch main battery output to the light via optocoupler, I documented one such device on a breadboard in the forum
3. The OEM ICR headset is crap, dunno what they pack if you order frame with side holes for cable routing, see the threads about headsets Non-ICR headset, internal frame cable guide conversion for the SZZS-specific CEF50 | ICR Headsets for the SZZS-specific CEF50 build
4. See Bafang M820 Firmware thread Generally use FW matching your engine's voltage.

Edit:
1. Honestly I believe there's no real reason to use chain guide. I haven't experienced a single chain drop in a regular use during my ~2500km of fairly aggressive riding. The narow-wide profile of included Scenix chainring + clutch on my M8100 derailleur retain chain very well.
2. I use Lezyne eBike Micro Drive 500 High Voltage (powered from main battery via aforementioned switching device)

Thanks for your replies.
Do you guys know if there is a compatible shift sensor for M820 ?

 

[voigtkampff]

Thanks for your replies.
Do you guys know if there is a compatible shift sensor for M820 ?

there is none, I investigated this area. many folks will tell that with good riding habits (decrease tension on pedals while shifting) none is needed in torque-sensing engine. the problem I see is that the engine shutoff isn't immediate after you stop pushing on pedals and there is a slight "overrun" which will often lead to engine executing the shift with lots of force.

 

[Yozha]

Yesterday I went to a local manufacturer of carbon fiber parts - it turns out to be quite a complicated process. You need a geometrically correct part, a matrix is made on its base, and layers of carbon fiber are glued onto the matrix. Making one cover for the engine will cost 250-300USD.
But I was recommended a good manufacturer of 3D parts.
Guys, do you think it is possible to print a strong cover at once on a 3D printer and what kind of plastic should be used for this (I don't understand anything about it at all)?

 

[TCFlowClyde]

Yesterday I went to a local manufacturer of carbon fiber parts - it turns out to be quite a complicated process. You need a geometrically correct part, a matrix is made on its base, and layers of carbon fiber are glued onto the matrix. Making one cover for the engine will cost 250-300USD.
But I was recommended a good manufacturer of 3D parts.
Guys, do you think it is possible to print a strong cover at once on a 3D printer and what kind of plastic should be used for this (I don't understand anything about it at all)?

I ordered a 3D printed small clamp for my old M600 display from a local print shop two years ago. That was $30 USD. I can only think something 10x the size as the motor guard would unlikely retail under $200 USD.. Also, I broke it on the install, too brittle and no choice on the type of plastic.

It might make sense if you have access to your own 3-D printer and are just paying material costs. Obviously, most of us don't have that level of 3-D printer access.

 

[Yozha]

I ordered a 3D printed small clamp for my old M600 display from a local print shop two years ago. That was $30 USD. I can only think something 10x the size as the motor guard would unlikely retail under $200 USD.. Also, I broke it on the install, too brittle and no choice on the type of plastic.

It might make sense if you have access to your own 3-D printer and are just paying material costs. Obviously, most of us don't have that level of 3-D printer access.

Friends, I ordered a cover seal from a trusted supplier. At the consultation the manufacturer said that the problem of our protection is poor adhesion between the layers of plastic. My cover will be made of TOTAL GF-10 plastic, which has good adhesion between the layers and is strong enough for our purposes.

 

[Yozha]

Friends, I ordered a engine cover from a trusted supplier. At the consultation the manufacturer said that the problem of our protection is poor adhesion between the layers of plastic. My cover will be made of TOTAL GF-10 plastic, which has good adhesion between the layers and is strong enough for our purposes.
The main thing now is that the 3D model I found a few pages ago is correct. Hopefully in 2-3 weeks I will have a ready copy on my hands.

 

[Txurrispo]

Friends, I ordered a engine cover from a trusted supplier. At the consultation the manufacturer said that the problem of our protection is poor adhesion between the layers of plastic. My cover will be made of TOTAL GF-10 plastic, which has good adhesion between the layers and is strong enough for our purposes.
The main thing now is that the 3D model I found a few pages ago is correct. Hopefully in 2-3 weeks I will have a ready copy on my hands.

Please. Maintain us informed. Shows promising

 

[Yozha]

Please. Maintain us informed. Shows promising

TOTAL PRO GF 10 - reference to the plastic. From the description it looks good

 

[TCFlowClyde]

How

Friends, I ordered a engine cover from a trusted supplier. At the consultation the manufacturer said that the problem of our protection is poor adhesion between the layers of plastic. My cover will be made of TOTAL GF-10 plastic, which has good adhesion between the layers and is strong enough for our purposes.
The main thing now is that the 3D model I found a few pages ago is correct. Hopefully in 2-3 weeks I will have a ready copy on my hands.

How much did your initial order cost?

 

[Yozha]

How

How much did your initial order cost?

About 100USD. The manufacturer said that the price is minimal and they will not reduce it if the quantity increases. I ordered two engine protectors - for myself and my friend (he has already ordered the frame))))

 

[TCFlowClyde]

About 100USD. The manufacturer said that the price is minimal and they will not reduce it if the quantity increases. I ordered two engine protectors - for myself and my friend (he has already ordered the frame))))

Sounds like a fair price.

 

[Adilka]

Hi! I placed an order for a CEF50 frame on Alibaba (size L purple chameleon, 48V 700WH battery), waiting for shipment.

I have now cane creek DB kitsuma air shock from my Deviate Highlander (size 210*55)

Can I use it on CEF50 without modification? Or 55mm stroke will be too much?

I know, that stroke on DB can be reduced (Cane Creek Suspension Support - Cane Creek Cycling Components) by 5mm very easy

So what is better - use it as it is, or reduce to 210*50?

thanks!

 

[TCFlowClyde]

Hi! I placed an order for a CEF50 frame on Alibaba (size L purple chameleon, 48V 700WH battery), waiting for shipment.

I have now cane creek DB kitsuma air shock from my Deviate Highlander (size 210*55)

Can I use it on CEF50 without modification? Or 55mm stroke will be too much?

I know, that stroke on DB can be reduced (Cane Creek Suspension Support - Cane Creek Cycling Components) by 5mm very easy

So what is better - use it as it is, or reduce to 210*50?

thanks!

I've run a 55 stroke on a large frame since last year no problem. But like you said try it first and see how it fits for you. I luv it!

 

[un..inc]

Can you tell me where I can find the breakdown of the frame suspension travel to stroke? 50, 52,5 , 55?

 

[TCFlowClyde]

Can you tell me where I can find the breakdown of the frame suspension travel to stroke? 50, 52,5 , 55?

Rough estimate: 150 mm OEM (210 x 50 shock) on a 50 mm stroke. 150 mm/50mm = 3 or 3:1 leverage ratio. Learned it from Mtbr.com a few years ago. Or just Google it.

Stroke: Functional travel:
-50 mm 150 mm
-52.5 mm 157.5 mm
-55 mm. 165 mm
-57 mm. 171 mm

 

[Adilka]

55 mm. 165 mm

That's why I'm aware about keeping 55mm stroke - maybe the wheel can hit the frame

 

[TCFlowClyde]

That's why I'm aware about keeping 55mm stroke - maybe the wheel can hit the frame

Possibly. But remember that the seat stays have no crossbridge to contact. I run a 27.5x2.8 tire. It's 28.75"tall with great clearance from the seat tube. A 29er should also clear it. But if not, then just shorten the stroke or go 27.5 wheel and keep the overstroke. Experiment. The bigger travel is worth it. IMHO

 

[saffa]

I'm also contemplating rather fitting a 210x55, if it's to close on the 29er wheel will look at swopping the rear wheel out, but going to give the 29er a go first. On another note, has anyone fitted a fox float X2 on the CEF50, are there any issues with the shock and frame touching?

Thanks again to all of you for your input into the CEF50, reading through this forum made me purchase this frame.

 

[un..inc]

I don't think the problem so far has been with the tyres on the frame, but with the joints in the rear triangle, which at some point are actuated further than they should be. At some point they could collide / rub against each other and break.
I think @TCFlowClyde had some minor problems with this?

 

[patdam]

That's why I'm aware about keeping 55mm stroke - maybe the wheel can hit the frame

No risks for contact between wheel and frame. BUT verify mechanical translation available for the swing arms/stays/bases at level of the axes.

May be SZZS have modified their frame ? but on mine 55 don't fit and i use 53 mm

 

[un..inc]

No risks for contact between wheel and frame. BUT verify mechanical translation available for the swing arms/stays/bases at level of the axes.

May be SZZS have modified their frame ? but on mine 55 don't fit and i use 53 mm

How did you verify that 55 did not fit? i think i have the newest frame and could test it...

 

[patdam]

How did you verify that 55 did not fit? i think i have the newest frame and could test it...

You mesure the length available between the rear shock axes (shock removed). With swing arm fully compresed (axes design provide mechanical limit), to verified if you have less than 155 mm available (210 - 55).

If you mesure exactely 155mm available, i recommand to use 53 (52.5), it's preferable to keep 2mm marging

 

[un..inc]

You mesure the length available between the rear shock axes (shock removed). With swing arm fully compresed (axes design provide mechanical limit), to verified if you have less than 155 mm available (210 - 55).

If you mesure exactely 155mm available, i recommand to use 53 (52.5), it's preferable to keep 2mm marging

I'll have to put some Volume Tokens inside my Damper anyways and therefore need to take it out. I'll try to measure this after your instructions.
Thank you!

 

[Yozha]

You mesure the length available between the rear shock axes (shock removed). With swing arm fully compresed (axes design provide mechanical limit), to verified if you have less than 155 mm available (210 - 55).

If you mesure exactely 155mm available, i recommand to use 53 (52.5), it's preferable to keep 2mm marging

With the frame assembled without shock, the axle spacing is 148,5 mm. The 29` wheel does not touch the frame at this. Frame size M.

Am I correct in understanding that a 55mm stroke on a 210mm shock is acceptable?

 

[Yozha]

I've decided to keep 50 mm for now. In winter, I will think whether I need to increase the stroke. But overall, there is potential.
The only thing is the link needs to be filed (I peeled the paint off a bit)