Fixing Loose Crank and Bushing Connections in eitech Models

Quick answer

A loose crank and bushing connection in an eitech model usually comes from a worn or slightly undersized bushing, or from the crank being over-tightened. The fix is to replace the bushing with a new one or to adjust the crank's clamping force.

Diagnosis and fix

• Symptom: The crank handle wobbles or spins freely without turning the attached mechanism. You may also hear a clicking or scraping sound when turning.
• Likely cause: The bushing inside the crank has worn down or the crank's clamping screw is too tight, crushing the bushing and creating play.
• Corrective action: First, loosen the M4 screw that holds the crank to the shaft by a quarter turn. If the wobble disappears, stop here—the joint was over-tightened. If the wobble remains, remove the crank and inspect the bushing. If it appears cracked, flattened, or worn, replace it with a new eitech Crank with Bushing M4 (01410). Reassemble and tighten the screw just until snug—do not force it. If the crank still wobbles after replacing the bushing, the crank arm itself may have a stripped thread. In that case, replace the entire crank assembly.
• When to stop or choose another option: If the model uses a non-standard shaft diameter (e.g., from a different brand), the eitech M4 bushing may not fit. In that case, stop and source a bushing matched to your shaft size.

Product facts

• Crank with bushing M4: The eitech Crank with Bushing M4 (SKU 01410) is a replacement part from the Manufaktur line, designed for M4 crank systems. Using this exact part ensures the bushing is the correct size and material for a snug, wobble-free fit in your eitech model.