compareeHub

YOU CAN BUILD A NEW BRAIN FOR AN E-BIKE ITS MAKER ABANDONED

A twenty-dollar ESP32 touchscreen replaces the dead app on a hubless e-bike its maker walked away from.

by Seth Alvo

FULL CAD BOM FIRMWARE DOCS

AutomationOpen-hardware

Built withESP323D printing

difficulty
●●●○○
time
an evening
license
MIT
repo
repo ACTIVE258 stars

WHAT YOU’LL NEED

1
Jump to section

COMPAREE VERDICT

If you own a Reevo and the original app is dead, this is how you get your bike back. Seth Alvo (with an AI assistant doing much of the initial Bluetooth reverse-engineering) decoded the protocol the Reevo's controller speaks, wrote firmware for a Freenove ESP32-S3 touchscreen, and published a two-piece printable case. You flash the board, set a PIN, and the bike unlocks without a phone or cloud account. It shows speed, battery and trip distance, and controls the headlight, badge light, kickstand lock and assist level. The bill of materials is essentially one board of about 20 dollars plus filament and wire. The one thing most likely to go wrong is the pairing passkey: any bike that was ever paired with the original app needs its passkey recovered by opening the bike and tapping the BLE module's debug output. And this will not work on another e-bike — the BLE commands are Reevo-specific. For Reevo owners, this is the difference between a working bike and an expensive ornament.

GOOD TO KNOW

  • —Complete PlatformIO firmware with a one-shot install script, a two-piece printable case (STL), and the reverse-engineered BLE protocol in docs/PROTOCOL.md.
  • —Bill of materials is a single Freenove ESP32-S3 2.8-inch touchscreen board (about 20 dollars).
  • —README walks through power wiring, flashing, PIN setup and passkey recovery, with a reference image of the BLE module solder points.
  • —MIT licence — unrestricted use, including commercial.
  • —This is for Reevo owners only; the BLE commands are specific to that bike's controller.
  • —No schematic, but the board is off-the-shelf and the code shows every pin assignment.

Parts to buy

3 items

From our check of the build. Exact quantities and part numbers are in the creator’s BOM.

  • Freenove FNK0104B ESP32-S3 2.8-inch capacitive touchscreen boardFind
  • USB-C cable and thin wireFind
  • Since the screen itself can read the passkeyFind

BUILDS OF THE WEEK

Five open-source builds worth your weekend, every week.

Checked like this one: what’s really in the repo, what it costs, how hard it is. One email, unsubscribe anytime.

Can I build this?

PrintA two-piece case for the touchscreen board (front bezel and rear shell, STL in the repo); PLA or PETG both work.
BuyFreenove FNK0104B ESP32-S3 2.8-inch capacitive touchscreen board (about 20 dollars), USB-C cable and thin wire; a USB-UART adapter is optional if your bike was ever paired with the original app, since the screen itself can read the passkey.
ToolsSoldering iron and fine wire, multimeter, 3D printer, a Mac or Linux computer for the install script (PlatformIO), and a Reevo e-bike.
SkillsSoldering fine wires to the bike's BLE module and mainboard, running a one-shot install script to flash the ESP32, and basic 3D printing. Expect to take the bike apart if it was ever paired with the original app.
TimeAn evening for printing, flashing and mounting — plus a long session taking the bike apart if it was ever paired with the original app, because you have to read the BLE passkey off the main board.
Cost$ — the touchscreen board dominates the cost, everything else is filament and a bit of wire.
SafetyYou open the bike and solder to its mainboard, which also carries the 12 V and 48 V rails — remove the battery first and confirm with a multimeter that your pad reads 5 V before connecting the screen.

Build at your own risk. Projects involve tools, electronics and sometimes mains voltage — follow the creator’s safety notes.

More builds like this

All projects
VolAnti: an ESP32 box that hears drones by their propellers, so fibre-optic FPV cannot hideOpen-hardwareA braille display that costs a fraction of the commercial ones because it uses a single moving cellOpen-hardwareA do-it-yourself fingerprint unlock for a Mac, built to avoid Apple's 149 dollar Touch ID keyboardOpen-hardware

Start here

Navigation into the creator’s own docs — we don’t rewrite the guide, we route you to the source.

  1. 1.Read the README and confirm you have a Reevo e-bike with a dead app (This will not work on any other e-bike model.)
  2. 2.Order the Freenove ESP32-S3 2.8-inch touchscreen board(About 20 dollars, widely available. The README links the exact model.)
  3. 3.Print the handlebar case STL while the board ships(PLA or PETG both work; the case is not water-resistant, so avoid riding in the rain.)
  4. 4.Run the install script to build and flash the firmware, then set your PIN on the screen(The code shows the pin configuration and BLE service UUIDs.)
  5. 5.Solder power wires, mount the screen, and test the unlock(Power the screen from a 5V and GND pad on the bike's mainboard, and check the pad with a multimeter first, as the README instructs.)

KNOWN ISSUES

  • This is for the Reevo e-bike only — the BLE commands are hard-coded for its motor controller and will not work on another brand or model.
  • The company behind the Reevo (Beno) has shut down and the official app is dead, so a replacement like this is how owners keep the bike usable.
  • The firmware targets the Freenove FNK0104B ESP32-S3 board. Another ESP32-S3 "CYD" board can work, but you must set its pins, panel driver and touch chip in display_config.h, using one of the included profiles or the board's schematic.
  • The printed case is not water-resistant — the creator says not to ride a Reevo in the rain anyway — and PLA can soften if left in strong sun; PETG or nylon hold up better.
  • The creator treats the Reevo as a collector's item now: ride it carefully and seldom. The firmware adds a pedal-assist auto-timeout so the bike will not take off when you push it after it has been idle.
  • If your bike was ever paired with the original app, the default BLE passkey no longer works — recovering it means opening the bike and soldering two wires to the BLE module's debug UART, as the README explains.

Will this work on my other e-bike?

No. The BLE protocol and service UUIDs are specific to the Reevo's motor controller. You would need to reverse-engineer your own bike's Bluetooth commands.

Can I change the PIN after flashing?

Yes, without reflashing. The screen starts its own Wi-Fi access point with a web console where you can reset the PIN with the lockreset command. A master recovery code exists only if you enable it in your own user_config.h before you flash.

Does this need the original Reevo app installed?

No. The entire point is to replace the dead app. The screen talks directly to the bike over Bluetooth.

What if the company comes back or updates the app?

The company has shut down and the app is dead, so this is hypothetical. Both talk to the same BLE controller, but note that the original app changed the bike's pairing passkey when it first paired, which is exactly why owners now have to recover it to use this screen.

Community builds

No community builds yet — be the first, we feature the best ones.

Discussion1

FROM THE COMPAREE TEAM

The Reevo's company abandoned the project and the app died, and this screen gives owners a working dashboard again for about twenty dollars of parts. If a product you bought needed an app to work and the company disappeared, what would you try first?

CompareeTEAM13d agoedited

Practical notes from our verification: the repository is recent and active, with PlatformIO firmware and an install script, a protocol document describing the bike's BLE commands, and a two-piece printable case for the Freenove ESP32-S3 touchscreen board. The dashboard talks to the bike over Bluetooth and gives back speed, battery, lights, kickstand lock, assist level and a PIN unlock. The hard part is the pairing passkey: if your bike was ever paired with the original app, the passkey was changed, and the reliable way to recover it is to open the bike, remove the main board and read the BLE module's debug output through two soldered wires. The README walks you through that and through powering the screen from a 5V pad on the mainboard, with a warning to check it with a multimeter first. This is a Reevo-only solution, and it makes the bike usable again, not a different bike. Correction (4 October 2026): we re-checked this page line by line against the project's own repository, documentation and videos, and fixed errors in earlier versions.

Seth Alvo

Seth Alvo is a YouTube video creator (Berm Peak) and tinkerer who shares DIY projects. After Beno abandoned the Reevo and its phone app died, he built this replacement dashboard with help from Claude, which did the initial reverse-engineering of the bike's Bluetooth protocol.

GitHub

Star the project on GitHub

DISCLAIMER

  • Comparee is not the author of the projects featured here. All rights to each project belong to its creator — every page links to the original source, and we never host creators’ files.
  • Information is provided without warranty and may become outdated as projects evolve. Prices are indicative bands only — always check the creator’s parts list for current costs.
  • Building and operating any project is at your own responsibility. Protective equipment, safe workshop practice and compliance with local regulations are the builder’s responsibility.
GitHub repo