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Alert — Bosch Firmware 11.13.0 (April 2024)

The Bosch 11.13.0 update deployed in April 2024 via the eBike Flow app rendered SpeedBox 1.0, 1.1 and 1.2 (ordered before May 2024) inoperative on Bosch Smart System motors. If you have any Bosch tuning kit installed: disable automatic updates in eBike Flow immediately and verify compatibility before every firmware update.

eBike Firmware Updates & Tuning Kits — What You Must Know Before Updating

Every firmware update can silently strengthen your motor's detection algorithms — or brick an otherwise working tuning kit overnight. This guide covers the risks by motor brand and explains how to protect your kit before updating.

Why firmware updates matter for tuning kit users

Ebike motor manufacturers (Bosch, Shimano, Yamaha, DJI) publish regular firmware updates to add features, fix bugs and improve performance. But these updates also modify the motor's internal software — including its anomaly-detection routines.

A tuning kit works by modifying the signal sent to the motor controller. When Bosch or Shimano refine their detection algorithms, an update can make a previously undetectable kit suddenly visible — or simply non-functional.

The most documented example is Bosch firmware 11.13.0 (April 2024): pushed automatically through the eBike Flow app, it broke compatibility for SpeedBox 1.0, 1.1 and 1.2 units ordered before May 2024. Hundreds of users found their kit non-responsive overnight, with no prior warning.

A second, often underestimated risk: the eBike Flow app (Bosch) and E-TUBE Project (Shimano) can push updates automatically if you do not explicitly configure them otherwise. A Bluetooth connection while charging your bike in the garage is enough to trigger an unwanted update.

The universal rule: disable auto-updates if you use any tuning kit

Golden rule for all kit users

Regardless of your motor brand or kit type — disable automatic firmware updates in your motor app. Accept updates only after confirming compatibility on your kit manufacturer's website. There is no firmware rollback on modern Bosch or Shimano systems: once updated, you cannot go back.

Rules by motor brand

Bosch Smart System (Gen4, Gen5, SX)

Risk level: HIGH. Bosch is the most aggressive motor manufacturer in terms of detection. Each update can modify detection thresholds. The April 2024 firmware 11.13.0 is the benchmark incident.

How to freeze Bosch firmware — step by step in eBike Flow:

  1. Open the eBike Flow app on your phone
  2. Connect to your bike via Bluetooth
  3. Tap the menu icon (top-right) → Settings
  4. Select Firmware Updates
  5. Toggle Automatic Update to OFF
  6. You will still receive update notifications — do not accept until you have verified compatibility on speedbox-tuning.com, volspeed.eu or your kit manufacturer's site
  • Never accept an update offered by a dealer or workshop without verifying yourself first
  • Older Bosch Gen2 and Gen3 motors (round connector) use eBike Connect — less impacted, but caution still applies

Shimano EP8 / EP801 (and E series)

Risk level: MEDIUM — HIGH for EP801. The EP801 (DU-EP801, late 2022 onwards) has an internal anti-manipulation algorithm. Error E295 → 4 occurrences → E299: permanent motor lock, reversible only at an authorised Shimano workshop.
  • The E-TUBE Project app (iOS / Android) pushes updates via Bluetooth — set it to manual update mode before connecting to a bike with any tuning kit installed
  • Do NOT update if you have a tuning kit fitted, especially on EP8 / EP801 — verify compatibility on peartune.com or your kit manufacturer first
  • The EP801 Race Tune firmware (2025) removes the speed-assist cutoff in Race mode natively — favourable for tuning users, but the update process itself can alter detection; check kit compatibility before accepting
  • Error code E299 (permanent lock) is the major risk on EP801: never force a kit reconnection after an incompatible update
  • EP801-safe kits: PearTune MSO 3.0, BadassBox 4, Eplus Flash — see the Shimano tuning guide

Yamaha (PW, PW-X, PW-X2, PW-X3, PW-C2) — PW-LINK firmware

Risk level: MEDIUM — monitor closely. Yamaha PW-LINK firmware updates have so far been less disruptive than Bosch, but compatibility changes have occurred. Monitor kit manufacturer bulletins before each update.
  • Physically disconnect your kit before any firmware update via the Yamaha app — unplug the kit connectors, not just the battery
  • Updating with a kit still connected can cause a non-reversible initialisation error on some PW-X3 units
  • Reconnect the kit only after restarting the bike and confirming the motor system is stable
  • Check compatibility bulletins on your kit manufacturer's site before accepting any PW-LINK firmware update

TQ HPR (HPR40 / HPR50 / HPR60)

Risk level: LOW (currently).TQ's detection policy is less aggressive than Bosch. App updates have not broken existing kits to date — but the situation can change.
  • Check speedbox-tuning.com for TQ compatibility bulletins before any update
  • Low current risk, but apply the same precaution: disable auto-updates in the TQ app if a kit is fitted

DJI Avinox

Risk level: MEDIUM — watch closely. DJI updates the Avinox firmware silently through the mobile app. With DJI's track record for rapid software iteration, the compatibility risk is real.
  • Disable automatic updates in the Avinox Ride app if a kit is installed
  • Consult your kit manufacturer before every Avinox firmware update

How to check if your kit is still working after an update

  1. Fully restart the bike (power off + power on) after any firmware update
  2. Check the display for error codes. On Bosch, errors 503 or 507 can indicate a kit conflict. On Shimano EP801, E295 is the early warning before the irreversible E299
  3. Test kit activation using the normal procedure (Walk Assist held, dedicated button, etc.) in a safe area at low speed
  4. Confirm speed-assist behaviour: in tuned mode, motor assistance should continue above the legal cut-off. If assistance drops at the legal limit, the kit is no longer functioning
  5. If everything is normal, note the installed firmware version (visible in the app) — useful reference if a problem arises later

What to do if your kit stops working after an update

Do not force the kit

Do not repeatedly disconnect and reconnect the kit, or force pairing. On Bosch Smart System motors, each failed connection attempt with an incompatible kit can increment an internal error counter. Too many errors can trigger a lock that is difficult to reset even at a dealer workshop.

  1. Contact your kit manufacturer immediately. SpeedBox, PearTune, BadassBox and others typically publish a compatibility update within weeks of a problematic firmware release. Have your order number and installed firmware version ready.
  2. Leave the kit in place but inactive while waiting for a compatibility update. Do not remove it unless you are certain of the correct deactivation procedure — some kits must be deactivated before disconnection to avoid a motor error.
  3. Keep your bike usable in standard mode during this period. The legal speed limit will be active, but the bike functions normally.

Firmware rollback — why it is not possible

On modern Bosch Smart System and Shimano EP801 motors, rolling back to a previous firmware version is not possible. Firmware packages are cryptographically signed and the motor unit rejects any version lower than the currently installed one. No official or third-party tool exists to downgrade these systems.

Prevention is the only effective protection. Once an update is installed, you cannot reverse it — you must wait for a compatibility update from your kit manufacturer.

Pre-update checklist — before accepting any firmware update

Do this before accepting any firmware update
1Identify the firmware version being offered (visible in the app before installing)
2Go to your kit manufacturer's website (speedbox-tuning.com, peartune.com, etc.)
3Look for a compatibility bulletin specifically for that firmware version
4If no information is available: do not update — contact kit support first
5If compatibility is confirmed: note your current version, then proceed with the update
6After updating: restart the bike, confirm no error codes, test kit activation
7Yamaha only: physically disconnect the kit before starting the update

Choose a kit with a proven firmware update record

SpeedBox publishes compatibility bulletins within days of any Bosch or Shimano firmware release. BadassBox 4 (external) is immune to motor firmware changes — it never interacts with the motor electronics.

Shop SpeedBoxfrom £139BadassBox 4 — firmware-immune£130–145

FAQ

My SpeedBox kit stopped working after a Bosch firmware update. What should I do?
Contact SpeedBox support immediately via speedbox-tuning.com. Since the firmware 11.13.0 incident (April 2024), the SpeedBox team is experienced with this situation and typically publishes a compatibility update within a few weeks. Do not repeatedly reconnect and disconnect the kit — on Bosch Smart System motors, each failed connection attempt can increment an internal error counter, which may trigger a harder-to-reset motor lock.
How do I disable automatic updates in the Bosch eBike Flow app?
In the eBike Flow app: go to Settings → Firmware Updates → uncheck 'Automatic Update'. You will still receive a notification when a new firmware is available, but it will not install without your confirmation. Use that window to check compatibility on your kit manufacturer's website before accepting.
Can I roll back to an older firmware version on a Bosch or Shimano motor?
No — firmware rollback is not possible on modern Bosch Smart System or Shimano EP801 motors. Both manufacturers cryptographically sign their firmware packages and the motor unit will reject any version lower than the currently installed one. There is no official or third-party tool capable of downgrading these systems. Prevention — never updating without verification — is the only effective protection.
Is the Shimano EP801 Race Tune firmware (2025) safe to install with a tuning kit?
The EP801 Race Tune firmware itself is favourable to tuning users because it removes the speed-assist cutoff in Race mode. However, the update process itself can modify detection algorithms. Always verify compatibility for your specific kit (PearTune MSO 3.0, BadassBox 4, Eplus Flash, etc.) on the manufacturer's website before accepting the update via E-TUBE Project.
Does the firmware warning apply to all Bosch motors, including older Gen2 and Gen3?
The Bosch 11.13.0 incident specifically affected Bosch Smart System motors (Gen4 and later). Older Gen2 and Gen3 motors (round connector) use a different update ecosystem (eBike Connect, not eBike Flow) and were not impacted. However, caution is still recommended for any Bosch motor — always verify kit compatibility before accepting any firmware update.