Fiido d2s with d4s components

Hi guys

Qiuck question, I got second hand d2s which doesn't turning ON. As I will need to replace handlebar display and controller, I was thinking to order both parts for d4s to get little bit more features. To me motor on both ebikes looks identical, and other parts shouldn't cause any problems. Did someone tried to use those or upgrade d2s with aftermarket display and controller? Thanks

Ask Fiido via their website?

I did, their support worker doesn't seems to be much helpful in technical questions. They said that the g20 display unit were never mounted on d2s, which is not true. Also they mentioned that the motor is different on d4s, by tech. specifications I found, they are identical..

Hi and welcome, E-bike control systems have 'evolved' in a particular way. such that displays and controllers often share a specific communication protocol and format.

This changes from brand to brand and differences can even crop up within bike brands and model lines. SO the rule of thumb is if you need a new display - get it from the bikes supplier and only the one specifically for your bike. otherwise you are taking a gamble. Many who take the gamble end up in here and with no supplier replacement available get directed towards replacement controllers with paired displays. .

Hi and welcome, E-bike control systems have 'evolved' in a particular way. such that displays and controllers often share a specific communication protocol and format.

This changes from brand to brand and differences can even crop up within bike brands and model lines. SO the rule of thumb is if you need a new display - get it from the bikes supplier and only the one specifically for your bike. otherwise you are taking a gamble. Many who take the gamble end up in here and with no supplier replacement available get directed towards replacement controllers with paired displays. .

Hi, thanks for answer. I understand and totally agree with you. Anyway as I mentioned I would like to order both, handlebar display unit and controller for d4s. I wonder if anyone sees a potential problem in this. So, if someone could confirm for me whether the engines from both models are identical, in my opinion that is the only thing that could cause a compatibility problem

It is unlikely the motor will be a problem. Assuming both models are a 250W rated motor, they should use a standard 9 pin cable, and if they have the same wheel size, will be the same nominal rpm.

It is much more common to have issues with controller and display, but you plan to replace both as a set, so that should be fine.

However, I do NOT have first hand Fiido knowledge! Their customer service usually gets favourable reviews here, so maybe try again, you might get someone different/more knowledgeable!

Hi and welcome, E-bike control systems have 'evolved' in a particular way. such that displays and controllers often share a specific communication protocol and format.

This changes from brand to brand and differences can even crop up within bike brands and model lines. SO the rule of thumb is if you need a new display - get it from the bikes supplier and only the one specifically for your bike. otherwise you are taking a gamble. Many who take the gamble end up in here and with no supplier replacement available get directed towards replacement controllers with paired displays. .

Both models are fitted with 36V , 250w brushless motor. Design are different, battery on d4s has slightly larger capacity, but that's all. In my opinion, a controller and display unit from d4s should work with a d2s motor without any problems. Please correct me if I'm wrong. Thank you

I dunno, Probably a half hearted google led me here which sells d2 and d4 motors but only pictures the d4 motor connecting wires which are not terminated in the familiar 9 pin socket ;( -

Since you have the d2 bike can you see if the motor is connected with automotive sockets as pictures in the d4 motor ad above? if so your probably ok, otherwise you may have some soldering/crimping ahead.

Worst case scenario 1x controller uses power output math for speed output and the other uses a extra sensor input from the motor so you may loose a speed readout ??

Edited February 17, 20251 yr by thelarkbox

Both models are fitted with 36V , 250w brushless motor. Design are different, battery on d4s has slightly larger capacity, but that's all. In my opinion, a controller and display unit from d4s should work with a d2s motor without any problems. Please correct me if I'm wrong. Thank you

See earlier post, but yes, sounds like you should be fine. Can never be zero risk, but no obvious red flags. Battery size does not matter.

Hi guys

 

Qiuck question, I got second hand d2s which doesn't turning ON. As I will need to replace handlebar display and controller, I was thinking to order both parts for d4s to get little bit more features. To me motor on both ebikes looks identical, and other parts shouldn't cause any problems. Did someone tried to use those or upgrade d2s with aftermarket display and controller? Thanks

You can probably swap controller and display without problems as long as the motor has the standard 9-pin connector, and, more importantly, the battery only has two wires connecting it to the controller on both D2S and D4S. If either has more than two wires, it probably won't work.

I dunno, Probably a half hearted google led me here which sells d2 and d4 motors but only pictures the d4 motor connecting wires which are not terminated in the familiar 9 pin socket ;( -

 

Since you have the d2 bike can you see if the motor is connected with automotive sockets as pictures in the d4 motor ad above? if so your probably ok, otherwise you may have some soldering/crimping ahead.

 

Worst case scenario 1x controller uses power output math for speed output and the other uses a extra sensor input from the motor so you may loose a speed readout ??

I already checked all possible websites that are selling fiido parts, but there is lack of specs.. As you saying, the wires on the d4s photo from their website are not fitted in the terminal, anyway the wiring and colour coding are identical. Just swapping the pins in the terminal will do the job. Possible crimping or soldering is no problem, but in this case not required. I worried more about the speed sensor output. I contacted Fiido support again to send me detailed specs of both motors..

You can probably swap controller and display without problems as long as the motor has the standard 9-pin connector, and, more importantly, the battery only has two wires connecting it to the controller on both D2S and D4S. If either has more than two wires, it probably won't work.

Hi, thanks for reply. Both motors have 3 wires beside the 9 pin connector. Can I ask why this should be a problem?

Hi, thanks for reply. Both motors have 3 wires beside the 9 pin connector. Can I ask why this should be a problem?

If the battery uses two wires, it's dumb, and so is the controller. If it has more than that, it normally means that the controller communicates with the battery. It can only communicate if it has the correct comms protocols and identifications.

Hi, thanks for reply. Both motors have 3 wires beside the 9 pin connector. Can I ask why this should be a problem?

any thinner data wires Not the 2 x thicker gauge power wires from a battery to a controller would indicate a requirement for a battery /controller handshake similar to but infinitely more problematic than any display issues.

Motors generally have 9x connections 3 x thicker phase power wires( often blue green yellow), 1 x +5v logic level power supply (thin red wire) 1 x logic ground connection (thin black wire) 3 x hall sensor oututs (thin yellow blue green) and a speed hall sensor output - (white wire)/ or temp sensor output? sometimes a 10th connector.

The other 3 x wires are probably for connecting to a pas sensor fitted to the crank hence its similar placement.. I guess?

EDIT - xtra 3 wire connector could also be for brake or gear change sensor or even a back light? if any are situated in the rear motor area?

edit #2 if anything other than pas input and not a d2 feature only found on D4 bikes? simply not connecting should not be a problem

Edited February 17, 20251 yr by thelarkbox

Not being rude but have you first carried out the basics ?

Does the battery actually output correct voltage and does it take a charge ?

any thinner data wires Not the 2 x thicker gauge power wires from a battery to a controller would indicate a requirement for a battery /controller handshake similar to but infinitely more problematic than any display issues.

 

Motors generally have 9x connections 3 x thicker phase power wires( often blue green yellow), 1 x +5v logic level power supply (thin red wire) 1 x logic ground connection (thin black wire) 3 x hall sensor oututs (thin yellow blue green) and a speed hall sensor output - (white wire)/ or temp sensor output? sometimes a 10th connector.

 

The other 3 x wires are probably for connecting to a pas sensor fitted to the crank hence its similar placement.. I guess?

EDIT - xtra 3 wire connector could also be for brake or gear change sensor or even a back light? if any are situated in the rear motor area?

 

edit #2 if anything other than pas input and not a d2 feature only found on D4 bikes? simply not connecting should not be a problem

Thanks for explaining the wiring, anyway there is no extra 3 wires. By the 3 wires beside the terminal connector was meaning 3 thick phase power wires. I just double checked the controller/motor wiring and there is 5 wires (black, blue, yellow, red and green) on terminal and 3 phase wires, so total 8 for d2s. Also I checked photos of d4s controller and there is one white wire extra compare to d2s controller. So 9 in total (black, blue, yellow, red, green and white[speed sensor?]). That mean the motors are not identical and with d4s controller and display connected to d2s motor it would run but no speed reading...CORRECT?

Edited February 18, 20251 yr by SOURLEMONJUICE

Not being rude but have you first carried out the basics ?

Does the battery actually output correct voltage and does it take a charge ?

Hi, thanks for comment. I forgot to mention in firs post that the battery is fully charged and holding 41.8V over last few days. So battery is not the issue

Bellow is answer from Fiido support when I asked for both motors specs.

D4S motor: motor~20 "CZJB90TZ rear 36V 250W rear left inner outlet, disc brake OLD 137 6S thread 36H 13G black with one speed gauge, wire length 800mm, maximum speed 31km/h 9-core ordinary wire, phase wire 3C head, Hall 2 8-piece flange nut with rubber sleeve

D2S motor: 36V 16 inch high-speed integrated wheel motor, equipped with 6-speed flywheel, all sub black color, disc brake variable speed, imperial thread, 145mm on gear, load speed of 25 kilometers per hour, right outlet, with internal speed measurement, ordinary nine core wire length of 710mm (excluding wire stripping)

Still sounds good to me.

I think the six speed flywheel means freewheel, and the other one is single speed.

If you can make sense of the wiring it should work.

Thanks for explaining the wiring, anyway there is no extra 3 wires. By the 3 wires beside the terminal connector was meaning 3 thick phase power wires. I just double checked the controller/motor wiring and there is 5 wires (black, blue, yellow, red and green) on terminal and 3 phase wires, so total 8 for d2s. Also I checked photos of d4s controller and there is one white wire extra compare to d2s controller. So 9 in total (black, blue, yellow, red, green and white[speed sensor?]). That mean the motors are not identical and with d4s controller and display connected to d2s motor it would run but no speed reading...CORRECT?

Possibly ?

Bellow is answer from Fiido support when I asked for both motors specs.

 

D4S motor: motor~20 "CZJB90TZ rear 36V 250W rear left inner outlet, disc brake OLD 137 6S thread 36H 13G black with one speed gauge, wire length 800mm, maximum speed 31km/h 9-core ordinary wire, phase wire 3C head, Hall 2 8-piece flange nut with rubber sleeve

 

D2S motor: 36V 16 inch high-speed integrated wheel motor, equipped with 6-speed flywheel, all sub black color, disc brake variable speed, imperial thread, 145mm on gear, load speed of 25 kilometers per hour, right outlet, with internal speed measurement, ordinary nine core wire length of 710mm (excluding wire stripping)

ER Probably?? This is just theory on my part not based on direct experience with speed sensors

My first stab at a solution would be to hack wire in the sensor from a $2-3 aliexpress bike computer as it will come with an easy to fix to a spoke magnet too tho it migbt be a reed switch?? (2 wire connection not 3x) (connect ground and signal to test a reed switch) the wheel may have more than 1 x speed sensor magnet so if it seems like your reading 1/2 actual speed with correct wheel size set try adding a 2nd magnet... 40% chance of success??

if the cheap git bodge fails google/utube hall effect sensors and do a kosher diy job, different hall sensors trigger under different conditions, coffee utube 10 mins you will get it..

Edited February 18, 20251 yr by thelarkbox

Still sounds good to me.

 

I think the six speed flywheel means freewheel, and the other one is single speed.

 

If you can make sense of the wiring it should work.

They are both 6 speed, identical freewheel and handlebar shifter. Forgot to mention d4s has 20inch wheels and d2s 16inch wheels. Now I know d4s has one extra wire for speed sensor(?), so there will be probably issue with speed reading when use d4s components?

They are both 6 speed, identical freewheel and handlebar shifter. Forgot to mention d4s has 20inch wheels and d2s 16inch wheels. Now I know d4s has one extra wire for speed sensor(?), so there will be probably issue with speed reading when use d4s components?

It's going to be fairly expensive to buy the D4S parts. Do you have a price? If it was my bike, I'd buy a standard controller and LCD that you know will work. You can buy a speed sensor at the same time in case you need it. A top of the range KT one would be about £80 -£90 with throttle, PAS and speed sensor, so that you can guarantee that it's plug and play if you don't like wiring; or about £50 for a cheaper type, like Brainpower. If you're trying to get a better riding experience, it's better to pay the extra for the KT because it gives you the throttle as a power boost and other useful features.

It's going to be fairly expensive to buy the D4S parts. Do you have a price? If it was my bike, I'd buy a standard controller and LCD that you know will work. You can buy a speed sensor at the same time in case you need it. A top of the range KT one would be about £80 -£90 with throttle, PAS and speed sensor, so that you can guarantee that it's plug and play if you don't like wiring; or about £50 for a cheaper type, like Brainpower. If you're trying to get a better riding experience, it's better to pay the extra for the KT because it gives you the throttle as a power boost and other useful features.

Hi, I did some research and yes KT will be the solution. Thanks