Video Tutorials

Step-by-step video guides from the CEMOTO team.

Video Tutorials

Step-by-step video guides from the CEMOTO technical support library. Every video is embedded and plays inline — the written notes below each player cover what to check and in what order.

How to use these pages. Watch the video for the procedure, then use the short written list as the checklist. Each page is deliberately brief: the video is the instruction, the page is the reference.

Assembly and installation

Tutorial Covers
Unboxing & Assembling the D02 Electric Dirt Bike Crate to first ride, and the 0-gear power-on sequence
Unboxing & Assembling the B57A Folding eBike Unfolding, latch checks, stem and pedals
Installing CEMOTO Pedals Including the left-hand thread that cross-threads crank arms
Installing the D-Series Battery Side Guards Handed panels and a fitting order that prevents cracks

Setup and configuration

Tutorial Covers
D-Series P-Setting Guide All of P01–P17, and the three that cause real faults
Changing the Speed Unit from KM/H to MPH Parameter P02 — and the two settings people change instead
How to Limit Speed Three methods, and why a speed cap is not gentler acceleration
Resetting the Controller to Factory Settings FarDriver dongle procedure, and when a reset is the wrong answer

⚠ Read the P-Setting Guide before changing any parameter. P03 and P14 can damage the pack, controller and motor, and out-of-spec values are not covered by warranty.

Error code diagnostics

Each is an ordered check — cheapest and most likely first.

Code Tutorial The key insight
E02 Brake Error E02 A signal fault, not a brake fault. The lever not returning is the usual cause
E06 Low Voltage Error E06 Often just a flat pack, poor connections or cold weather
E07 Motor Error E07 Rarely the motor. Phase connectors and the hall sensor plug first
E08 Throttle Error E08 Usually the twist grip binding, not the throttle unit
E09 Controller Error E09 Heat, voltage sag and a shorted phase all present as E09
E13 Front Light Error E13 Connectors and water ingress, not the headlight
— Horn Not Working Button and spade connectors. The D02 Track ships without a horn
— Battery Not Charging Work from the wall socket outward
— CEMOTO Won't Turn On Start with the 0-gear sequence — it is not a fault

E10 and E12 have no dedicated video. Both are almost always connector or cable problems — reseat everything in the affected circuit, and see the general Wiring & Connectors guide.

Maintenance and repair

Tutorial Covers
Installing a CEMOTO Motor Phase order, hall plug seating, mounting and first-run checks
Removing a CEMOTO Motor Safe removal and what to inspect while it is out
Installing the Front Disc Brake Caliper centering — the step that stops the brake dragging
Changing the Lock Set on a D02 Ignition lock replacement and the wiring checks

Electrical and wiring

Tutorial Covers
Connecting the Wires — Connector & Wiring Guide Every connector on the bike, the wiggle test and reading heat damage

Before you start any job

Checklist Page
Fastener torque values Torque & Fastener Reference
Scheduled maintenance intervals Maintenance Schedule
Parts availability Spare Parts & Compatibility
Model specifications D-Series · eBikes
Warranty terms before you open anything Warranty
Reaching support Contact & Support

⚠ Warranty warning. Opening an electrical component yourself — the motor, controller, battery or display — voids the warranty on that part. Removal and refitting for a warranty replacement should follow CEMOTO support's instructions. Damage caused by parameter values outside specification is also not covered. See Warranty Claims.

Technical Guides — Video Library

CEMOTO publishes step-by-step assembly and troubleshooting videos. This page is the catalog; each video has its own page in the Video Tutorials section, where the video is embedded inline with a short set of written notes.

Watch for the pattern. Several CEMOTO technical guides follow the same principle: check these before replacing parts. Most reported faults trace back to a connector, an adjustment or a charge state — not a failed component. Working through the checks saves both time and money.

Where to find the tutorials

All 23 videos have dedicated pages with the player embedded inline and brief written notes:

Section Tutorials
Assembly D02 dirt bike · B57A folding eBike · Pedals · Battery side guards
Setup P-Setting guide · Speed unit · Limit speed · Controller reset
Error codes E02 · E06 · E07 · E08 · E09 · E13
Faults without a code Horn not working · Battery not charging · Won't turn on
Maintenance Motor installation · Motor removal · Front disc brake · D02 lock set
Electrical Connecting the wires

→ Go to the Video Tutorials index

The complete video catalog

Assembly guides

Video Applies to Tutorial page
Folding eBike B57A — Unboxing & Assembly B57A folding eBike Assembly guide
Off-Road Electric Dirt Bike D02 — Unboxing & Assembly D02 Classic, D02 Track Assembly guide
How to Install a CEMOTO Motor — Step-by-Step Tutorial D-series Installation guide
How to Remove a CEMOTO Motor — Step-by-Step Tutorial D-series Removal guide
How to Install the Front Disc Brake on a CEMOTO Electric Dirt Bike — Step-by-Step Guide D-series Brake guide
How to Install CEMOTO Pedals eBikes Pedal guide
How to install the left and right battery side guards for the CEMOTO D series D-series Side guard guide
How to change the lock set on the D02 D02 Lock set guide

Setup and configuration

Video What it covers Tutorial page
D-Series P-Setting Guide in 20 Seconds Controller parameter menu P-Setting guide
Change Speed Unit from KM/H to MPH Parameter P02 Speed unit guide
How to Limit Speed on Your CEMOTO Electric Dirt Bike — Easy Setup Tutorial Restricting top speed Limit speed guide
How to Reset CEMOTO Controller to Factory Settings — FarDriver Tutorial FarDriver default restore Controller reset guide

Technical support — error codes

Video Error code Tutorial page
CEMOTO Battery Not Charging? What Would You Check First? Charging fault Charging diagnostics
CEMOTO E02 ERROR? Check THESE Before Replacing Parts! E02 — Brake Error E02 guide
CEMOTO E06 Error? What Would You Check First? E06 — Low Voltage Protection E06 guide
Cemoto E07 Error — Motor & Wiring Troubleshooting Guide E07 — Motor Error E07 guide
E08 Error — Check the Throttle Before Replacing Parts E08 — Throttle Error E08 guide
E09 Error — Check These Before Replacing the Controller E09 — Controller Error E09 guide
E13 Error? Don't Swap the Headlight Yet — Check This First E13 — Front Light Error E13 guide
CEMOTO Won't Turn On? What Would You Check First? Power / start-up Won't turn on
Horn Not Working — Check These Before Replacing Parts Horn circuit Horn guide
Would You Know How to Connect These Wires? Wiring and connectors Wiring guide

Written reference: Display & Error Codes · Display & Settings

Written guides and articles

Beyond the video library, CEMOTO publishes written service guides covering a wide range of ownership, maintenance and repair topics. Where a topic matches a page in this documentation center, the corresponding page is linked.

Battery and electrical

Battery safety, charging, transport and disposal · battery storage temperature and charging practice · battery health testing · battery voltage and amp-hours explained · battery life planning before replacement · battery replacement cost · battery replacement connectors and compatibility · charger troubleshooting · charger compatibility checks · charging safety checklist · charging at the trailhead · removable vs integrated batteries · cold weather performance

→ Battery Care & Charging · Charging Faults · Battery Not Charging · Low Voltage E06

Motor, controller and display

Motor cut-outs under load · controller compatibility and upgrade · controller, display replacement and DIY repair · modular vs proprietary systems · wiring diagram and fault tracing · harness and connector compatibility

→ Motor & Controller Faults · Motor Error E07 · Controller Error E09 · Connecting the Wires · Display & Settings

Brakes, tires and suspension

Brake checks — inspect, test or stop riding · brake pad replacement and wear · brake fade · brake noise · hydraulic vs mechanical brakes · tire pressure and tire width trade-offs · tire types and tread selection · suspension setup

→ Brakes · Brake Error E02 · Front Disc Brake Installation · Tires, Wheels & Suspension

Maintenance and service

Maintenance schedule · maintenance log and repairs · brake, chain and drivetrain service · cleaning an electric dirt bike · pre-ride checklists · emergency kit and recovery kit · spare parts kits

→ Maintenance Schedule · Maintenance Log · Drive & Transmission · Cleaning & Storage · Pre-Ride Inspection · Spare Parts

Ownership, transport and storage

Transport and carriers · garage and apartment storage · charging and storage rules for apartments · theft prevention · insurance and registration checklists · paperwork, title and registration verification

→ Cleaning & Storage · Riding Laws & Compliance

Riding and performance

Range calculation and real-world range · speed factors · rider weight and range · heavier bike stability · suspension and torque on steep trails · riding drills · safety gear · first-ride preparation · riding in rain and snow · water resistance ratings · street tire vs knobby vs mixed surface

→ Range Calculator · Range & Performance · Rider Fit & Sizing · Riding Laws & Compliance

Unboxing & Assembly

Unboxing & Assembly

Unboxing & Assembling the B57A Folding eBike

Unfolding the frame, verifying the latch, fitting the stem and pedals, and folding it back down correctly.

Applies to: B57A folding eBike

Folding eBike B57A | Unboxing & Assembly — if the player does not load, open the video on YouTube.

What you need

Tool Notes
4 / 5 / 6 mm hex keys Usually supplied
15 mm spanner Pedals
Torque wrench Recommended

Allow 30–45 minutes.

Steps

  1. Cut the carton open and lift the bike out with a second pair of hands — folding eBikes are awkward, not heavy.
  2. Open the frame hinge. Release the latch, swing the frame open until it stops.
  3. Verify the latch engages fully and the safety clip is closed. This is a load-bearing joint — test it by pushing down on the frame before you ride.
  4. Raise and clamp the stem. Fold the handlebar post up, close the clamp lever and confirm the tension is firm. If it moves under hand pressure, adjust the clamp screw.
  5. Fit the pedals. The left pedal is left-hand threaded — it tightens anticlockwise. Cross-threading here is the single most common assembly mistake; see Pedal Installation.
  6. Fit the seatpost to roughly hip height, then fine-tune once you can sit on the bike.
  7. Check the brakes and spin both wheels to confirm nothing rubs.
  8. Check tire pressure, then charge and power on.

Folding it back down

Reverse the process: loosen the stem clamp, fold the post down, then release the frame hinge and fold the two halves together. Route the cables so they are not trapped in the hinge.

Watch out for

Unboxing & Assembly

Installing the D-Series Battery Side Guards

A handed pair of panels that protect the pack — and a fitting order that stops you cracking them.

Applies to: D-series

How to install the left and right battery side guards for the CEMOTO D series? — if the player does not load, open the video on YouTube.

What you need

Tool Notes
Hex keys Usually supplied with the guards
Clean cloth Wipe the mounting surface first

Steps

  1. Identify left and right. The two panels are handed and will not swap — test-fit before tightening anything.
  2. Clean the mounting points. Grit trapped behind a panel is what cracks them.
  3. Start every fastener by hand before tightening any of them. Fit all bolts loosely first.
  4. Tighten evenly, in a diagonal pattern — little by little, alternating sides. Do not run one bolt down tight and then start the next.
  5. Check the panel clears the frame and cable runs with no forcing.
  6. Confirm the pack is still fully seated and the connector is undisturbed.

Why it matters

Battery side guards are protective, not cosmetic. They shield the pack from branch strikes and from debris thrown off the front wheel. A cracked guard still needs replacing, which is why fitting order matters.

Watch out for

Unboxing & Assembly

Unboxing & Assembling the D02 Electric Dirt Bike

Crate to first ride: front wheel, handlebars, brake lever, footpegs, the pre-ride check, and the 0-gear power-on sequence that catches most people out.

Applies to: D-series (D02 Classic, D02 Track, D03 Pro, D03 Beast)

Off-Road Electric Dirt Bike D02 | Unboxing & Assembly — if the player does not load, open the video on YouTube.

What you need

Tool Notes
4 / 5 / 6 mm hex keys Supplied with the bike
10 / 13 / 15 mm spanners Supplied with the bike
Box cutter or side cutters To open the carton — never cut deep enough to reach the bike
Torque wrench Recommended; see Torque Reference

Allow 45–60 minutes. Work on a clear, flat surface with room to walk around the bike.

Steps

  1. Cut the carton straps and lift the box off. Keep the carton — it is the safest way to transport the bike later.
  2. Remove the packaging holding the bars, front wheel and footpegs to the frame. Do not discard the hardware bag.
  3. Fit the front wheel. Raise the front of the frame, slot the wheel in, insert the axle and tighten — leave it snug, not final-tight, until the brake is checked.
  4. Fit the handlebars. Align the bar with the clamp marks, tighten the four clamp bolts evenly in a cross pattern.
  5. Fit the brake lever and check the brake. Squeeze the lever — firm, not spongy. See Installing the Front Disc Brake if the caliper needs centering.
  6. Fit the footpegs, then the mirrors and any further accessories supplied.
  7. Check the battery is seated and the connector is fully home.
  8. Run the pre-ride check before first power-on — see Pre-Ride Inspection.

The 0-gear trap

The most common "my new bike won't start" call.

On a D-series bike the display shows a gear number. If it reads 0, the bike will not drive — this is not a fault. Press the + button to select gear 1, then ride. See Won't Turn On.

Watch out for

Unboxing & Assembly

Installing CEMOTO Pedals

Two minutes of work — provided you get the left-hand thread the right way round.

Applies to: eBikes and eScooters with removable pedals

How to Install CEMOTO Pedals — if the player does not load, open the video on YouTube.

What you need

Tool Notes
15 mm pedal spanner Or a suitable adjustable spanner
Grease or anti-seize Recommended — pedals seize into crank arms over time

Steps

  1. Identify which pedal is which. They are marked L and R on the spindle, and they are not interchangeable.
  2. Identify which crank arm is which. The left crank is on the non-drive side (the side without the chain/gears).
  3. Start by hand. Thread each pedal in by hand for the first several turns. If it does not turn easily by hand, stop — you are cross-threading.
  4. The left pedal is left-hand threaded. To tighten it you turn anticlockwise. The right pedal tightens clockwise, like a normal bolt. This is the opposite of what most people expect.
  5. Tighten firmly with the spanner once it is hand-tight. It does not need to be brutal — the pedalling action tightens it further.
  6. Check both by rocking them side to side. Any movement means it is still loose.

Watch out for

Setup & Settings

Setup & Settings

Changing the Speed Unit from KM/H to MPH

One parameter — P02 — and the two settings people change by mistake instead.

Applies to: D-series

Change Speed Unit from KM/H to MPH — if the player does not load, open the video on YouTube.

The setting

P02 controls the speed unit:

Value Unit
0 KM/H
1 MPH

Steps

  1. Power on the bike and open the parameter menu (the display's settings entry).
  2. Navigate to P02.
  3. Change the value — 0 for KM/H, 1 for MPH.
  4. Save and exit the menu properly.
  5. Power cycle — off, then on.
  6. Confirm the speedo now reads in the unit you chose.

Watch out for

The two adjacent settings are not the speed unit, and changing them causes real problems:

If your speedo is reading a plausible but incorrect number, the unit is probably fine and P06/P07 is the real problem. See the P-Setting Guide.

Setup & Settings

Resetting the CEMOTO Controller to Factory Settings

The FarDriver dongle procedure — and the cases where a reset is the wrong answer.

Applies to: D-series with the FarDriver programmable controller

How to Reset CEMOTO Controller to Factory Settings | FarDriver Tutorial — if the player does not load, open the video on YouTube.

What you need

Item Notes
FarDriver Bluetooth dongle CEMOTO D-Series part — see Spare Parts
FarDriver mobile app Installed on your phone
A charged 12V auxiliary supply Some procedures need the controller held powered

Steps

  1. Locate the controller's programming connector — usually under the side panel or seat area.
  2. Plug in the dongle and power the bike on.
  3. Pair the dongle with the FarDriver app.
  4. Read the current parameters first and save or photograph them. A factory reset discards every value you have set, including any that were correct for your wheel size or voltage.
  5. Issue the factory reset from the app.
  6. Re-verify the critical parameters after the reset — particularly P03 (voltage), P06 (wheel diameter), P07 (magnets), P13 (magnet disk) and P15 (undervoltage). A generic factory profile will not necessarily match your bike.
  7. Power cycle and confirm the bike behaves normally at low speed.

When a reset is the wrong answer

A factory reset is not a diagnostic tool. Do not use it as a first response to an error code.

Situation Do this instead
An error code (E02, E06, E07, E08, E09, E13) Work the specific diagnostic — see Error Code Tutorials
A parameter you changed produced a fault Set that parameter back to its previous value
Intermittent electrical faults Check connectors — see Wiring & Connectors
A genuinely scrambled or replaced controller A reset is the right tool

⚠ Warranty note. Damage caused by parameter values outside specification is not covered. Never use a reset as a way to load a more aggressive profile than the bike is rated for. See Warranty Claims.

Setup & Settings

How to Limit Speed on a CEMOTO Electric Dirt Bike

Three ways to cap the top speed — and what each one actually does.

Applies to: D-series

How to Limit Speed on Your CEMOTO Electric Dirt Bike | Easy Setup Tutorial — if the player does not load, open the video on YouTube.

The three methods

Method Parameter What it does
Speed limit P08 Caps top speed. 0 = no limit; the value is in km/h
Drive mode P10 0 = power, 1 = electric, 2 = coexist
Start intensity P12 0–5 — how hard the motor comes in from a stop

Steps

  1. Decide which you actually want. If the concern is top speed, use P08. If the concern is how abruptly the bike launches, that is P12, not P08.
  2. Open the parameter menu and navigate to the chosen parameter.
  3. Set the value. For P08, the number is in km/h — 25 km/h ≈ 16 mph.
  4. Save, exit, and power cycle.
  5. Test at low speed in a safe open area, then confirm the cap holds.

A speed cap is not the same as gentler acceleration

A common misconception. Lowering P08 limits how fast the bike will eventually go. It does not change how hard it accelerates up to that speed — the bike still comes off the line just as sharply. For a new or younger rider, P12 is usually the more useful setting.

Watch out for

Setup & Settings

D-Series P-Setting Guide (P01–P17)

Every controller parameter, what it does, and the handful that cause real faults when set wrong.

Applies to: D-series with the FarDriver controller

D-Series P-Setting Guide in 20 Seconds — if the player does not load, open the video on YouTube.

Before you change anything

⚠ Read this page fully first. Two parameters — P03 (voltage) and P14 (current limit) — can damage the battery, controller and motor if set outside specification. Damage caused by out-of-spec parameter values is not covered by warranty. See Warranty Claims.

Write down the current value of any parameter before you change it.

The parameters

Parameter Setting Notes
P01 Display brightness / backlight Cosmetic
P02 Speed unit — 0 = KM/H, 1 = MPH See Changing the Speed Unit
P03 Voltage level Must match your pack — 36V / 48V / 72V. Wrong value = real faults
P04 Dormancy / sleep timer Minutes before the display sleeps
P05 Backlight brightness Cosmetic
P06 Wheel diameter Affects speedo accuracy
P07 Speed signal magnets 1–255. Wrong value makes the speedo read wrong
P08 Speed limit 0–100 km/h. 0 = no limit
P09 Zero-start / non-zero-start Whether the throttle works from a standstill
P10 Drive mode 0 = power, 1 = electric, 2 = coexist (pedal + motor)
P11 Assist sensitivity 1–24
P12 Start intensity 0–5. How hard the motor comes in from a stop
P13 Magnet disk count 5 / 8 / 12 — must match the PAS disk fitted
P14 Controller current limit Default 12 A, range 1–20 A. Above specification damages the controller and motor
P15 Undervoltage threshold Protects the pack from over-discharge. Do not lower this to chase range
P16 ODO reset Long-press up for ~5 seconds to clear
P17 Cruise control On/off

The three that actually matter

After changing a parameter

  1. Save / exit the menu properly.
  2. Power cycle — off, then on.
  3. Confirm the expected change (speedo unit, speed cap, assist level).
  4. Record what you changed in the Maintenance Log.

Maintenance & Repair

Maintenance & Repair

Changing the Lock Set on a D02

Ignition lock replacement, the wiring checks to do while you are in there, and the 0-gear confusion that follows.

Applies to: D02 Classic, D02 Track

How to change the lock set on the D02 — if the player does not load, open the video on YouTube.

What you need

Tool Notes
Hex keys / socket set Panel and lock retaining hardware
Replacement lock set See Spare Parts for the current price
Camera Photograph the wiring before disconnecting

Steps

  1. Power off and remove the key.
  2. Remove the panels covering the lock. Keep the fasteners together — they are small and easy to lose.
  3. Photograph the wiring at the back of the lock before you unplug anything.
  4. Disconnect the lock's connector, releasing the tab rather than pulling the wires.
  5. Remove the lock's retaining nut or clip and withdraw the lock from the frame.
  6. Fit the new lock, checking the barrel operates smoothly before you tighten anything down.
  7. Reconnect the wiring in the same orientation, then tug-test each connector.
  8. Refit the panels and test: power on, confirm the display lights.

After refitting: the 0-gear check

If the bike powers on but will not drive, check the gear display. It almost certainly reads 0. Press + to select gear 1 — this is not a fault. See Won't Turn On.

Watch out for

Maintenance & Repair

Installing the Front Disc Brake — Step-by-Step

Caliper centering is the step that stops the brake dragging — and the one most often rushed.

Applies to: D-series

How to Install the Front Disc Brake on a CEMOTO Electric Dirt Bike | Step-by-Step Guide — if the player does not load, open the video on YouTube.

What you need

Tool Notes
Hex keys Caliper and lever mounting bolts
Torque wrench Caliper bolts are safety-critical — see Torque Reference
Clean rag and isopropyl alcohol Never let brake fluid or oil touch the disc or pads

⚠ Never squeeze the brake lever with the caliper removed and the disc out. It pushes the pistons out and you will have to reset them.

Steps

  1. Fit the disc to the wheel if it is not already mounted, and check it runs true.
  2. Mount the caliper with its bolts just snug — loose enough that the caliper can still slide side to side.
  3. Squeeze and hold the brake lever. This lets the caliper self-center on the disc.
  4. With the lever still held, tighten the caliper bolts to specification. This is the step that prevents a dragging brake.
  5. Release the lever and spin the wheel. The disc should run through the caliper with only a light, even contact — and no scraping in one spot.
  6. Fit the lever and set its reach and angle so it is comfortable and fully returns.
  7. Check the brake cut-off: with the bike powered, squeeze the lever and confirm the motor stops. If not, see E02.
  8. Bed the pads in with a few gentle stops from moderate speed before hard use.

Watch out for

Maintenance & Repair

Installing a CEMOTO Motor — Step-by-Step

Wiring orientation, phase order, mounting and the first-run checks that confirm you got it right.

Applies to: D-series

How to Install a CEMOTO Motor | Step-by-Step Tutorial — if the player does not load, open the video on YouTube.

What you need

Tool Notes
Socket set Axle nuts and mounting hardware
Torque wrench See Torque Reference
Insulating tape / heat shrink For any repaired cable run
Cable ties Replace the ones you cut

⚠ Warranty note. Opening a motor voids the warranty on that part. Follow CEMOTO support's instructions for a warranty replacement. See Warranty Claims.

Steps

  1. Support the bike so the wheel is clear of the ground.
  2. Route the motor cable before mounting. Fit the cable into its frame guides first — it is far harder once the wheel is in place.
  3. Seat the motor in the swingarm/dropouts, checking any spacers or torque washers go back in the same positions.
  4. Fit the axle nuts finger-tight, then torque to specification with the wheel aligned.
  5. Connect the three phase wires. They are color-matched — match them exactly. Wrong phase order causes rough running or no rotation at all.
  6. Connect the hall sensor plug. Small, multi-pin, easy to seat only halfway. Push until it clicks, and check no pin has backed out.
  7. Refit the chain / belt and set the tension — approximately 15 mm slack where a chain is used.
  8. Check the brake runs true and does not bind on the disc.
  9. Rotate the wheel by hand before applying power. It must turn freely with no rubbing.
  10. Power on and test at walking pace, then check for error codes. E07 here means the phase or hall connection needs rechecking — see E07.

Watch out for

Maintenance & Repair

Removing a CEMOTO Motor — Step-by-Step

Safe removal, and the inspection you should do while the motor is out.

Applies to: D-series

How to Remove a CEMOTO Motor | Step-by-Step Tutorial — if the player does not load, open the video on YouTube.

What you need

Tool Notes
Socket set Axle nuts and mounting hardware
Side cutters Cable ties — you will cut some
Pen and phone camera Photograph every connector before you unplug it

⚠ Warranty note. Opening a motor voids the warranty on that part. Removal for a warranty replacement should follow CEMOTO support's instructions. See Warranty Claims.

Steps

  1. Power the bike off and let it stand.
  2. Support the bike with the wheel clear of the ground.
  3. Photograph the wiring at the motor before touching anything — phase order and connector orientation are easy to forget.
  4. Release the chain / belt tension and move it clear of the sprocket.
  5. Disconnect the three phase wires and the hall sensor plug. Pull connector bodies, never the wires.
  6. Remove the axle nuts and note the position of any spacers or torque washers.
  7. Lower the wheel out of the frame. It is heavy — support it as it comes free.
  8. Inspect before you go further: phase wire chafing, hall plug pin condition, bearing play, and any sign of water ingress at the cable entry.

While the motor is out

Check Why
Bearing play Spin the wheel and feel for roughness or lateral movement
Cable entry Water ingress here causes intermittent faults for months
Sprocket wear Far easier to replace now than after refitting
Brake disc condition Check for warping or scoring while it is off the bike

Wiring & Electrical

Wiring & Electrical

Connecting the Wires — Connector & Wiring Guide

How to tell the connectors apart, the wiggle test, and how to read heat damage before it strands you.

Applies to: D-series and eBikes

Would You Know How to Connect These Wires? — if the player does not load, open the video on YouTube.

The connectors you will meet

Connector Where Watch for
Three phase wires Motor to controller Chafing at the swingarm; color order matters
Hall sensor plug Motor to controller Small multi-pin; seats only halfway very easily
Main battery connector Pack to harness High current — look for heat discoloration
Charge port Pack / frame Water ingress and bent pins
Display cable Display to controller Causes E10 when loose
Brake switch leads Levers to controller Triggers E02 when pinched
Throttle lead Grip to controller Triggers E08 when chafed

The wiggle test

The single most useful diagnostic on an electric bike.

  1. Power the bike on.
  2. Gently flex one cable run at a time — at the connector, and where it passes a frame edge.
  3. Watch the display while you do it.

If the fault appears, changes or disappears as you flex, you have found an intermittent connection. That beats any amount of meter work.

Reading connector damage

Sign Meaning
Green or white deposit Corrosion — usually water ingress
Brown or black discoloration Heat from resistance — the connector is a bottleneck
Melted or deformed housing Serious heat; replace the connector, do not re-use it
Backed-out pin Push it home; if it will not stay, replace the terminal
Stretched or split seal No longer water-resistant — replace

Good practice

Error Code Fixes

Error Code Fixes

Battery Not Charging — What to Check First

Work from the wall socket forward: outlet, charger, charge port, pack. Stop when you find the break.

Applies to: D-series and eBikes

CEMOTO Battery Not Charging? What Would You Check First? — if the player does not load, open the video on YouTube.

Check in this order

Work from the wall outward. Each step rules out one link in the chain.

  1. The wall socket. Test it with something else. Obvious, and regularly the answer.
  2. The charger. Does its indicator light come on? Feel whether it warms up. A charger that stays completely cold is a suspect. Confirm the price and voltage on Spare Parts before ordering.
  3. The charge port on the bike. Look for bent pins, corrosion, debris or water ingress. Reseat the plug firmly and check it is fully home.
  4. The charge fuse. Many packs have an inline fuse on the charge circuit. Check it before condemning anything.
  5. The pack's own connector. Reseat the main battery connector and look for heat discoloration — a high-resistance connection prevents charge current reaching the cells.
  6. Try a slow charge and watch. If the pack is deeply discharged, some chargers will not start a normal charge cycle.
  7. Temperature. Charging a very cold pack can be blocked by the BMS. Let it come to room temperature before retrying.
  8. Only then suspect the pack. See Battery Care & Charging.

⚠ Never use a charger that is not rated for your pack's voltage. A 72V charger on a 48V pack will damage it. Confirm voltage before ordering a replacement.

Decision guide

Finding Action
Socket dead Use another outlet
Charger cold and dark Replace the charger — confirm voltage first
Charge port damaged or wet Clean and dry; replace if pins are bent
Charge fuse blown Replace the fuse and investigate why it blew
Pack cold Allow it to reach room temperature
Everything checks out Contact Support before replacing the pack
Error Code Fixes

Brake Error E02 — Check These Before Replacing Parts

E02 is a signal fault, not a brake fault. The lever not returning fully is the usual cause — and it costs nothing to fix.

Applies to: D-series · Error code: E02

CEMOTO E02 ERROR? Check THESE Before Replacing Parts! — if the player does not load, open the video on YouTube.

What E02 means

E02 = Brake Error. The controller monitors the brake circuit and raises E02 when it sees a signal state it does not expect.

The brake circuit does two jobs: operates the brake, and cuts motor power when the lever is applied (a safety interlock). E02 relates to the electrical signal, not the hydraulic braking force. A bike can have working brakes and still show E02.

⚠ Do not dismiss it as "just electrical". If the lever does not cut motor power, the interlock is not protecting you.

E02 is not a diagnosis of worn pads, low fluid, a warped disc or air in the line — those cause poor braking, not E02. See Brakes.

Check in this order

  1. Does the lever return fully? The most common cause by far. Squeeze and release slowly. Any gap means the switch may be held on. Check for grit in the pivot, a bent lever, or a grip/handguard fouling it. Clean and lubricate, then retest.
  2. Inspect the brake switch and its connector. Look for backed-out pins, corrosion, heat discoloration or a pinched lead where it leaves the lever. Disconnect and reseat — pull the connector body, not the wire.
  3. Test each lever separately. Squeeze front only, then rear only, and note which one triggers the error. That isolates the fault to one circuit.
  4. Trace the wiring from the levers to the controller. Turn the bars lock to lock while watching for a lead that pulls taut or chafes.
  5. Check the controller's brake input pin and reseat the main connector. If E09 or E10 appear alongside E02, suspect the controller.
  6. Consider conditions. Water in a connector, mud around the lever, ice in the pivot, or a crash can all trigger E02.

Decision guide

Finding Action
Lever does not return fully Clean or lubricate; replace the lever if bent
Connector corroded or loose Clean and reseat; replace if pins are damaged
Lead chafed through Repair or replace the lead
Error only in wet conditions Dry and treat the connectors
Persists with the brake circuit disconnected Suspect the controller — see E09

After the fix

Power cycle, then test the cut-off: with the bike powered, squeeze each lever and confirm the motor stops. If the error returns immediately you have not found the cause — do not ride with a known brake interlock fault.

Error Code Fixes

Low Voltage Error E06 — What to Check First

E06 usually means the pack is flat, the connections are poor, or it is simply cold — not that the battery has failed.

Applies to: D-series · Error code: E06

CEMOTO E06 Error? What Would You Check First? — if the player does not load, open the video on YouTube.

What E06 means

E06 = Low Voltage Protection. The pack voltage has dropped below the protection threshold and the controller has cut power to prevent over-discharge.

That threshold is a protection, not a fault in itself — it is doing its job. The question is why the voltage fell that low.

Check in this order

  1. Charge the pack and retry. If E06 clears and stays clear, the pack was simply flat. Nothing is broken.
  2. Check the charge state properly. Does the charger reach full and stop, or does it terminate early? An early cut-off points at the charger or the pack. See Battery Not Charging.
  3. Inspect the main battery connector and fuse. A high-resistance connection sags under load and reads as low voltage. Reseat the connector and check for heat discoloration.
  4. Consider temperature. Usable capacity drops sharply in the cold — roughly 70 % at 14 °F versus 90–95 % at 70 °F. A pack that is fine in summer can trip E06 on a cold morning. This is normal behavior, not a failure.
  5. Check P15 (undervoltage threshold). If it has been lowered to chase range, restore it. See the P-Setting Guide.
  6. Only then suspect the pack. A pack that trips E06 on a genuine full charge, in mild conditions, with clean connections, is a candidate for replacement.

Decision guide

Finding Action
Clears after charging and stays clear Normal — the pack was discharged
Charger terminates early Test the charger; charge time should match the spec
Connector warm or discolored Reseat or replace the connector
Happens only in cold weather Expected — warm the pack before charging and allow for reduced range
P15 lowered Restore it to specification
Full charge, mild weather, clean connections, still trips Contact Support

Watch out for

Error Code Fixes

Motor Error E07 — Motor & Wiring Troubleshooting

E07 rarely means the motor is dead. Phase connectors and the hall sensor plug are the usual culprits.

Applies to: D-series · Error code: E07

Cemoto E07 Error – Motor & Wiring Troubleshooting Guide — if the player does not load, open the video on YouTube.

What E07 means

E07 = Motor Error. It covers hall sensor faults, phase wiring faults and genuine internal motor faults.

It does not distinguish between them. That is why E07 has a deserved reputation for triggering unnecessary motor replacements.

Check in this order

  1. Inspect the motor's main connector. Unplug it, look for backed-out pins, corrosion or heat discoloration, and reseat it firmly.
  2. Check the three phase wires. They carry heavy current and are the most stressed connectors on the bike. Look for a chafed or pinched run where the cable passes the swingarm or frame edge.
  3. Check the hall sensor plug. This is the small multi-pin connector at the motor. A single bent or backed-out pin here produces E07 with a perfectly healthy motor.
  4. Wiggle test with the bike powered: flex the motor cable gently. If the error appears or disappears, the cable or connector is faulty.
  5. Confirm the wheel turns freely with the power off. A dragging brake or a seized bearing can present as a motor fault.
  6. Check for E09 alongside E07. If both appear, the problem may be at the controller rather than the motor.
  7. Only then suspect the motor itself. See Motor Removal and Motor Installation.

Decision guide

Finding Action
Connector loose, corroded or discolored Clean and reseat — no cost
Damaged cable section Repair or replace the cable
Bent hall sensor pin Straighten or replace the plug
Wiggle test changes the fault Cable or connector fault — no motor replacement needed
Wheel does not turn freely Investigate the brake or bearing first
E07 and E09 together Check the controller — see E09
Everything checks out Contact Support before ordering a motor

⚠ Warranty note. Opening the motor yourself voids the warranty on that part. Removal and refitting for a warranty replacement should follow CEMOTO support's instructions. See Warranty Claims.

Error Code Fixes

Throttle Error E08 — Check the Throttle Before Replacing Parts

A twist grip that does not return is far more common than a failed throttle unit.

Applies to: D-series · Error code: E08

E08 Error — Check the Throttle Before Replacing Parts — if the player does not load, open the video on YouTube.

What E08 means

E08 = Throttle Error. The controller is not seeing the throttle signal it expects — usually because the grip is not returning to the idle position, or because the signal path is broken.

Check in this order

  1. Does the twist grip return to idle on its own? Release it and watch. It should snap back fully. If it stays part-open, the controller reads a permanent throttle input. Check for grit in the housing, a fouled grip, or a bar-end pushing into the grip.
  2. Reseat the throttle connector. Look for backed-out pins, corrosion or a pinched lead where it leaves the grip.
  3. Wiggle test with the bike powered — flex the throttle lead and watch for the error appearing or disappearing.
  4. Check for physical damage to the throttle body — a crash or drop commonly cracks the housing.
  5. Check the wiring run to the controller for chafing at the steering head.
  6. Only then order a throttle. See Spare Parts for the compatible part and current price.

⚠ Safety. A throttle that does not return is a runaway risk. Do not ride the bike until it is fixed. Power down before inspecting.

Decision guide

Finding Action
Grip does not return fully on its own Clean and lubricate the housing; check bar-end clearance
Connector corroded or loose Clean and reseat — no cost
Lead chafed or pinched Repair or replace the lead
Housing cracked Replace the twist throttle
Error persists with the throttle disconnected Suspect the controller — see E09
Error Code Fixes

Controller Error E09 — Check These Before Replacing the Controller

Heat, voltage sag and a shorted phase all present as E09. The controller is the last suspect, not the first.

Applies to: D-series · Error code: E09

E09 Error — Check These Before Replacing the Controller — if the player does not load, open the video on YouTube.

What E09 means

E09 = Controller Error. It indicates a controller-internal failure — or, far more often, a condition upstream that the controller is correctly reporting.

An expensive part to replace by guesswork. Confirm the causes below first.

Check in this order

  1. Let it cool. Sustained hard use in hot conditions causes genuine thermal faults. If the code appears only after a long hard ride and clears when cold, that is the answer.
  2. Check supply voltage. A sagging pack or a high-resistance main connection starves the controller. Charge fully, reseat the battery connector and check the fuse. See Low Voltage E06.
  3. Check the phase wires and the motor circuit. A shorted phase can present as a controller fault. Inspect for chafing and check the resistance between phase wires.
  4. Check every controller connector for corrosion, backed-out pins and heat discoloration.
  5. Check for E07 or E10 alongside E09. Both narrow the fault to the motor circuit or the communications path rather than the controller.
  6. Check the controller's mounting and heat path. A controller with no airflow behind a blocked panel will run hot.
  7. Only then replace the controller. See Spare Parts for the compatible part and current price.

Decision guide

Finding Action
Only after sustained hard use Thermal — allow cooling and check airflow
Pack low or connector hot Charge, reseat, check the fuse — no cost
E07 alongside E09 Focus on the motor circuit — see E07
E10 alongside E09 Focus on the display cable and comms
Phase wire chafed or shorted Repair or replace the cable
All checks pass, code persists Genuine controller failure — confirm with Support first

⚠ Warranty note. The controller carries a 12-month warranty period. Opening it voids the warranty on that part — follow CEMOTO support's instructions. See Warranty.

Error Code Fixes

Front Light Error E13 — Don’t Swap the Headlight Yet

Connectors and water ingress cause E13 far more often than a failed headlight.

Applies to: D-series · Error code: E13

E13 Error? Don't Swap the Headlight Yet — Check This First — if the player does not load, open the video on YouTube.

What E13 means

E13 = Front Light Error. The controller is not seeing the expected state on the headlight circuit — an open circuit, a short, or a signal it does not recognize.

Check in this order

  1. Inspect the headlight connector. Unplug it, look for corrosion (green/white deposit), backed-out pins or heat damage, and reseat firmly. This is the most common cause.
  2. Look for water ingress. If E13 appeared after a wet ride or a wash, dry the connector and treat the contacts — do not replace anything yet.
  3. Wiggle test with the bike powered: flex the headlight lead and watch for the error appearing or disappearing.
  4. Trace the lead from the headlight back to the controller. Check for chafing where it passes the steering head and at the fork.
  5. Test the headlight itself. Does it illuminate at all? A light that works but still raises E13 points at the signal path, not the lamp.
  6. Only then replace the headlight assembly — see Spare Parts for the compatible part and current price.

Also check the tail light and brake light circuit if your model links them to the same feed.

Decision guide

Finding Action
Connector corroded or loose Clean and reseat — no cost
Error only after water exposure Dry and treat the contacts
Wiggle test changes the fault Lead or connector fault
Lamp does not illuminate, wiring sound Replace the headlight assembly
Lamp works, wiring sound, error persists Check the controller and comms
Error Code Fixes

Horn Not Working — Check These Before Replacing Parts

A silent horn is usually the button or a loose connector, not the horn itself.

Applies to: D-series (the D02 Track ships without a horn)

Horn Not Working — Check These Before Replacing Parts — if the player does not load, open the video on YouTube.

Before you start

The D02 Track is supplied in a track configuration without a horn. If your bike has no horn at all, this is not a fault — check your model's specification first. See D02 Track.

Check in this order

  1. Press the button firmly and listen. Confirm you are pressing the horn button and not the mode or indicator button.
  2. Check the button itself. Remove it from the bar and look for corrosion or a stuck contact. This is the most common cause of a silent horn.
  3. Inspect the horn's spade connectors. They vibrate loose on a dirt bike. Push each one fully home and check for corrosion.
  4. Check the mounting. The horn earths through its bracket on many bikes. A loose or freshly painted bracket can break the circuit.
  5. Test the horn directly on a known 12V supply if you have one — this isolates the horn from the wiring in one step.
  6. Trace the feed back to the harness and check for a blown fuse or a chafed lead.

Decision guide

Finding Action
Button stiff, corroded or stuck Clean or replace the switch
Spade connector loose Push home; replace the terminal if corroded
Bracket loose or insulated Restore a clean earth path
Horn works on a direct 12V supply Wiring or switch fault, not the horn
Horn dead on a direct supply Replace the horn
Error Code Fixes

CEMOTO Won’t Turn On — What to Check First

Start with the 0-gear sequence. It is not a fault, and it catches out new owners constantly.

Applies to: D-series and eBikes

CEMOTO Won’t Turn On? What Would You Check First? — if the player does not load, open the video on YouTube.

Check in this order

  1. Is the display showing gear 0? The most common cause. The bike will not drive in gear 0 — press + to select gear 1. The bike is not broken. See the D02 Assembly Guide.
  2. Is the power switch / electric door lock on? Confirm the key or switch is in the running position.
  3. Is the battery charged and seated? Reseat the main connector. See Battery Not Charging if it will not take a charge.
  4. Is the kill switch or side-stand cut-off engaged? Some models will not run with the stand down or a cut-off switch active.
  5. Is the brake lever stuck on? A lever that does not return keeps the brake interlock engaged — see E02.
  6. Check the display cable. A display with no power at all may simply have a loose connector. See Wiring & Connectors.
  7. Check the main fuse.
  8. Check for an error code. Note it and work the matching tutorial — see the error code index.

Decision guide

Finding Action
Display reads gear 0 Press + to select gear 1 — not a fault
Power switch off Turn the electric door lock on
Pack flat Charge it
Kill switch or stand cut-off active Reset it
Brake lever not returning See E02
Completely dead, no display Check the display cable and main fuse