Bosch Motor Problems

[Motounion]

Does anyone know what the problem may be with my Bosch motor it made a loud clunk and now I have no modes at all.
I had a "error" message on the display but that has now gone but the bike wont go past 10 mph and the modes do nothing any thoughts ?
Much appreciated.

 

[Zimmerframe]

Do you know which Bosch it is ?? Should be in the bike spec's in theory if you're unsure.

Also, which display are you using (as it had an error message and won't change modes - or does change modes, but you can't feel any difference ??????)

Then the usual questions to help with diagnosis.

Has it had any good pedal strikes ?

Has it been extensively submerged/used in wet weather a lot/jet washed/sat on the back of a car in the rain ?

 

[Stihldog]

Hmmm , sounds strange. Like Zim said , Was there a peddle strike?

The Bosch CX Gen 4 motor is pretty robust. The bracket bolts could begin to sheer after a severe peddle strike or the crank arms could bend. I’ve never seen or heard of a bent shaft, which could affect the motor internals.

As far as water ingress …it’s possible, but for 4 years I’ve ridden in all types of weather and have completely submerged the bike and myself several times. I never power wash though. I have added a bit of diaeletric grease to the motor electrical plugs (seals only) for some additional protection.

It kinda sounds like something internal (motor) has happened. Share what you’ve found.

 

[RiderOnTheStorm]

Knowing the error code or message would help with troubleshooting the problem at hand and possibly give some clues.

Do you have a LBS nearby who can connect to your bike with the bosch e-bike diagnostic tool (software)? The latest error messages are saved on the motor and can be viewed from the tool.

 

[Motounion]

Hi Guys thanks for the replies.
The bike is Decathlon Stilus V2 the motor is a GEN4 Bosch with a purion display.
No error code is now displayed but the bike will not move between modes although the display shows it does.
after some reseach I belive the issue to be the torque sensor inside the motor.
Thankfully the bike is still just within warranty.

 

[Zimmerframe]

@Bearing Man , any ideas ?

 

[Tomblarom]

There is this guy, that refurbishes and repairs Bosch, Yamaha & Brose motors. He's surely able to help. Based in Germany eBike-Doktor eBike-Motor Ersatzteile + Motorkomponenten für BOSCH, BROSE, YAMAHA , etc.

 

[Bearing Man]

@Bearing Man , any ideas ?

Although rare, these motors can slip from time to time, and this can be quite a "clunk" sometimes (bit like a chain jumping a tooth on a sprocket). Due to the fact that there are a few different electronic issues going on, power levels won't shift, bike wont assist over 10mph and no codes, my best guess would be that this "clunk" has damaged or "confused" something on the printed circuit board (brain) inside the motor. Thank heavens for warranties

There is this guy, that refurbishes and repairs Bosch, Yamaha & Brose motors. He's surely able to help. Based in Germany eBike-Doktor eBike-Motor Ersatzteile + Motorkomponenten für BOSCH, BROSE, YAMAHA , etc.

Olaf (The eBike Doktor) is our very good partner in Germany, I can safely say that he is a great guy and very experienced in most motors and parts.

 

[jackamo]

May want to go direct to Bosch as going through decathlon will add weeks to sorting the issue.