Worn bearings
Metallic noises or vibrations are often a sign of dry or worn internal bearings.
Practical guide: how to identify the cause of noise and which interventions you can do yourself for a silent motor.
Quick steps, common mistakes and FAQ answers 2025.
Metallic noises or vibrations are often a sign of dry or worn internal bearings.
A dry or overly tight chain causes squeaks and cyclic noises while pedalling.
If the motor was reassembled incorrectly after servicing, knocking and abnormal noises may be noticed.
Dust and mud inside cause creaks: always keep the compartment clean after rides.
| Noise | Main cause | Quick solution | Expert's note |
|---|---|---|---|
| Creaking at low speed | Dry or contaminated bearings | Lubricate bearings (only if experienced) or replace at Bosch centre. | Avoid high-pressure washing in the motor area. |
| Squeaking while pedalling | Dry or dirty chain | Clean the chain, lubricate with specific oil and adjust tension. | Also check sprockets and rear derailleur. |
| Toc toc on release | Loose frame bolts | Check the tightening of motor/frame bolts with a torque wrench. | Request the official Bosch tightening map. |
| Metallic noise uphill | Worn gears | Replace damaged gears (authorised workshop). | Avoid excessive stress when cold. |
*Official Bosch 2025 data and Whistle mechanics feedback.
Practical guide: how to identify the cause of noise and which interventions you can do yourself for a silent motor.
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