Fiido D21 User manual

1.Brake power off system
2.Light button
（ Click oncepower on/off）
3.Horn button
（ Click the button once to signal the whistle ）
4.Power on/off button
（Long press turn on/off electric power mode）
5.Power adjustment
（Click once to shift gears, a total of 3 gears）
6.Press the handle
（Press the handle increase the gear tooth）
7.Power off brake
8.Battery level
（Display remaining battery）
9.Speed
（Display current speed）
10.Electric assist gear
（ Display power gear number）
11
12.USB output port
.Press the handle
（Press the handle reduce the gear tooth）
1
3
5
7
6
11
7
3
km/h
2
3
4
59
8
10
１
12
（Charging via the built-in USB interface）

D21
D21

D21

High quality Lithium-ion 36V 11.6Ah

* When the battery is used up, it should be fully charged in time. The green light on the charger indicates full charge.Long-term underpowered storage will affect the performance of the battery.
* When cross the pool, water section, please pay attention to the wading height is not higher than the hub, prevent motor damage due to water inflow.Do not use high pressure water gun to clean,
so as not to damage the electronic components and wiring due to humidity.
* Add some lubricating oil to the chain and flywheel of the bike to avoid wading and rusting
* It is best to charge the battery in an ventilated, dry place.Direct sunlight or rain can have a bad effect on the performance of batteries and chargers.When charging,
the battery and charger should be away from other sources of heat.
* Connect the battery before charging, and then plug it into the electric supply .After charging, pull out the electricity first, and then pull out the battery end.If do not follow the steps,
it will cause a fire when connecting the battery end.
VII．Daily maintenance and basic trouble shooting
Brake abnormal sound or
wheel rotation resistance
Seat tube slide down
Difficulty in folding bicycle
Handlebars are not straight
Saddle loose (slide up and down)
Chain often falls off
1.Check whether the end of the brake cable is stuck.
2.Slight friction can be adjusted by fine-tuning the end of the line
3.Adjust the brakes to ensure that the brake pad and brake disc clearance is balanced
4.If the brake pads are worn, replace brake pads.
1.The set screw of the seat tube clamp is not tightened. Adjust the set screw.
2.Dry folding joints cause folding difficulties, can use lubricating oil to lubricate the joints.
1.Loosen the standpipe fixing screw, readjust the handlebar, and then tighten the standpipe fixing screw.
1.Check whether the saddle fixing screw is tightened. Retighten the saddle bottom fixing screw with the hex tool
2.The loose fixing screw of the saddle slides up and down, resulting in the sliding teeth
of the rack of the seat tube clamp code.It need to replace the seat tube clamp code.
1.Check whether the chainset is deformed and if the chainset is deformed ,it need to replace the chainset
2.Check whether the rear derailleur is loose,relock the rear derailleur and then lock the screw.
2.Check whether the anti-skid bushing inside the seat tube clamp is damaged ,if it's broken, replace the anti-skid bushing.
1.Check whether the spring at the folding joint is out of shape, or the spring is pulled
out without return, if the spring is damaged ,it needs to be replaced.
Fault code Cause of the malfunction
E001
E002
E003
E004
E005
E006
Communication issues
Throttle issues
Brake lever issues
Motor hall issues
Motor issues
Controller issues