Green Mamba CEF50 - 900Wh

[borysgo2]

Hi
Found a bit of a time and finished up my CEF50 frame. Long story short:
-FORK: 170MM BOMBER Z1 COIL
-SHOCK: BOMBER CR + COIL SPRING
-BATTERY: 12S4P @ SAMSUNG 53G 2170, JBD BMS
-WHEELS: SYNCHROS
-BRAKES: IIIPRO4
-DRIVETRAIN: SLX + 38T CHAINRING
-REST: AS YOU CAN SEE
-WEIGHT: 21.75KG
-HEAD ANGLE: 63.5DEG

Overall happy with the build. After I have dismantled the frame for painting, found that some aluminum spacer washers were damaged due to parts were hammered in during assembly before. Had to take off a bit of the original paint to make a bit more clearance to make life a bit easier.
DIY battery is located in the frame as low as possible to keep the center of gravity of the bike in right spot (about 15mm of the motor).
Battery ''marketing'' capacity 5.3*4*43=911Wh --> I think plenty for a long ride.
I have blanked the hole on top tube as I am not planning to use it. Surprised that rear triangle is nice and stiff enough.

A few pics, bellow:

 

[402.ac]

Nice bike! How do the brakes work? And what about the coil shock? I'm not sure whether to install a coil shock or an air shock when my frame arrives.

 

[Sherman]

Looks really nice! But looking at the tires, what's the use case for this bike?

 

[borysgo2]

Nice bike! How do the brakes work? And what about the coil shock? I'm not sure whether to install a coil shock or an air shock when my frame arrives.

Thanks
Have to do some proper ride. Done only about 2.5km off-road, coil at 23% sag, goes easily through the travel, so my first impression is progressive coil or air shock. But let me say, You are looking for a comfort not 10m jumps, linear coil will be perfect. In my setup, back end is very sensitive to the small bumps.
If You are not sure what shock to get, at first answer yourself, what are your requirements ?
Comfort and not so much crazy stuff = coil.
Good mid stroke support,jumps, etc. + crazy stuff = air shock.

Brakes need to bed in, but I have them also in differed bike. Modulation and brake force is OK, but You have to use more force than shimano slx brake leavers. Shimano leavers fell more ON-OFF like, they have servo wave --> variable leverage ratio.

IIIPro4 - they have fixed, linear leverage ratio, so it is easier to modulate it but have to use more force.

Regards

 

[borysgo2]

Looks really nice! But looking at the tires, what's the use case for this bike?

I just took some wheels of the shelf, tires and tubes are coming off soon.

BTW, those Ruban tires are not so bad at all. The only thing is a bit weak sidewall.

Regards

 

[402.ac]

Thanks
Have to do some proper ride. Done only about 2.5km off-road, coil at 23% sag, goes easily through the travel, so my first impression is progressive coil or air shock. But let me say, You are looking for a comfort not 10m jumps, linear coil will be perfect. In my setup, back end is very sensitive to the small bumps.
If You are not sure what shock to get, at first answer yourself, what are your requirements ?
Comfort and not so much crazy stuff = coil.
Good mid stroke support,jumps, etc. + crazy stuff = air shock.

Brakes need to bed in, but I have them also in differed bike. Modulation and brake force is OK, but You have to use more force than shimano slx brake leavers. Shimano leavers fell more ON-OFF like, they have servo wave --> variable leverage ratio.

IIIPro4 - they have fixed, linear leverage ratio, so it is easier to modulate it but have to use more force.

Regards

I don't do crazy jumps, but I like having support in the mid-range. Might a progressive spring be enough? If it's not a problem, how much do you weigh and what spring rate are you using? Is the shock at 50 or 55 stroke?
I'll be interested to hear your feedback once you've ridden more.

 

[borysgo2]

I don't do crazy jumps, but I like having support in the mid-range. Might a progressive spring be enough? If it's not a problem, how much do you weigh and what spring rate are you using? Is the shock at 50 or 55 stroke?
I'll be interested to hear your feedback once you've ridden more.

My weight is about 92-95kg, frame size L, spring 600LBS shock came of orbea rise = 210x55

IMHO progressive spring will be enough.

 

[borysgo2]

Hi.
A bit of a riding done. So far used only one battery charge since new.
Battery: 12S4P = 48 pcs of Samsung 53G1 cells.

During first charge I have done:
-total distance on the bike 124km
-total elevation on strava 2488m
-total distance on strava 110km
-battery drained to 3.0V per cell
-about: 30% Eco
50% Tour
20% Sport and Sport+
-FW: CRX30PC4313E102004.5_230721 (the newest one for active riders)

I am positively surprised by the Samsung 53G1 cells, they not any worse than M58 from LG I have in other bike.

CEF50 - rear coil shock --> in my opinion standard linear coil spring is OK for this frame. Suspension is rather on the active side but not wallowy at all.
Headset got a bit loose - had to retighten it a bit.
Only complain is to rather soft aluminum bolts with small/shallow 4mm allen key. The key hole is a bit too easy to strip, especially if You try to tighten the bolt via the shallower end.

Happy with the build.

Regards
Peter

 

[temon10]

Can u share detail of your DIY battery?

 

[borysgo2]

Can u share detail of your DIY battery?

Basically the battery is: 12S4P @ SAMSUNG 53G 2170, JBD BMS
I have made 12S3P battery and than added another 12S1P to it, joined by 1^2mm wires. Cells are glued together with TEC7 adhesive, sides of the battery are reinforced with 1mm fiber glass board (same as the PCB is made of, but with no copper on it). All taped up and wrapped.
Additionally I am using ideal diode PCB on the charging side to avoid problems in case of any short or faulty charger.
Cells are coming from nkon.nl - have very good experience with this shop, highly recommended.

Regards

 

[Charly]

Hello, did you have any problems with the brake caliper bolts?

 

[MrFixit]

Hi.
A bit of a riding done. So far used only one battery charge since new.
Battery: 12S4P = 48 pcs of Samsung 53G1 cells.

During first charge I have done:
-total distance on the bike 124km
-total elevation on strava 2488m
-total distance on strava 110km
-battery drained to 3.0V per cell
-about: 30% Eco
50% Tour
20% Sport and Sport+
-FW: CRX30PC4313E102004.5_230721 (the newest one for active riders)

I am positively surprised by the Samsung 53G1 cells, they not any worse than M58 from LG I have in other bike.

CEF50 - rear coil shock --> in my opinion standard linear coil spring is OK for this frame. Suspension is rather on the active side but not wallowy at all.
Headset got a bit loose - had to retighten it a bit.
Only complain is to rather soft aluminum bolts with small/shallow 4mm allen key. The key hole is a bit too easy to strip, especially if You try to tighten the bolt via the shallower end.

Happy with the build.

Regards
Peter

View attachment 161774

Hi Peter, can you tell me what you mean about the latest firmware is for active riders? I am looking to change mine from the 4.3 version as the motor seems to be in constant boost mode. There is no support difference between levels 1-4. consequently, the battery capacity (410wh) is used up very quickly.

 

[borysgo2]

Hi Peter, can you tell me what you mean about the latest firmware is for active riders? I am looking to change mine from the 4.3 version as the motor seems to be in constant boost mode. There is no support difference between levels 1-4. consequently, the battery capacity (410wh) is used up very quickly.

The 4.5 firmware forces You to work harder, it looks like ramps up the power slower and needs bigger rider's input to give full power. If You would like to work a bit harder and do more km per Wh than 4.5 is the way to go.

Regards

 

[MrFixit]

Thanks, I will give it a go. For your info, today I received from Jean 1.5_eMTB_230721 firmware. Is this an old firmware?

 

[borysgo2]

Thanks, I will give it a go. For your info, today I received from Jean 1.5_eMTB_230721 firmware. Is this an old firmware?

The firmware bellow is the one I use. It is for more active riders. It is still 13Amp firmware.

 

[Charly]

CEF50 Full 18kg 835Wh Charly Szzsbike Spain distributor

 

[Kenk3589]

Hey for the cef 50 to fit a coil shock, is there any changes made when compared to 2023? when I built up my bike, I remember we couldn’t use coil shock? Did any thing change in the frame since then? Or can we always add a shock if we wanted to go thy way?

 

[borysgo2]

Hey for the cef 50 to fit a coil shock, is there any changes made when compared to 2023? when I built up my bike, I remember we couldn’t use coil shock? Did any thing change in the frame since then? Or can we always add a shock if we wanted to go thy way?

Factory have made some modyfication to the frame at some point and coil shock fits OK. Only early releases had problem with coil shock.
Regards