This is well known issue for experienced technicians. Apart for balancing cause the other reason for vibration at these speeds is rim not matching hub diameter.
I guess rim manufacturer supplied BMW with out of spec rims.
It seems like new generation of service technicians needs instructions even for basics and BMW just released it for them. Ask your dealer to open following link on BMW intranet:
https://pumap.bmwgroup.com/puma/measure/get.do?oid=52131175&lin
Measure no.
51742297-02
Subject
Steering wheel torsional vibrations/vibrations at speeds of between
60 - 130 km/h
Release date (mm/dd/yy)
9/12/12
Status
Approved
Organization
V4-R1, CAR
Vehicles affected
E series
F20 F21 F30 F31
Engine Body
Production period (from/to)
(mm/dd/yy)
/
Comment on production period
Feedback (all cases relating t
measure up to) (mm/dd/yy)
Complaint
Customer complaints due to wheel-excited steering wheel torsional vibrations between 60-130 km/h.
Cause
Wheel/tyre combination/drive unit flange or wheel bearing
alloy wheel on the wheel hub outside tolerance
Measure
In the event of a customer complaint, work through the following procedure (before starting the procedu
the complete wheel must be tested for tyre pressure and damage):
Note: Check for flat spots. Rim check on balancing machine, max. 0.3 mm
radial run-out. Otherwise, replace the rim.
Please see the notes in the Repair Instructions 3610715.
Check the wheel centring of the light-alloy rim on the wheel hub. To do so, clean the contact surfaces
the wheel hubs and the light-alloy rims, and only slightly tighten the wheels. Using a feeler gauge at the
bottom position (see attachment 1), determine the maximum play. Play of 0.1 mm is still within the
permissible tolerance. Play of 0.15 mm would be outside the permissible tolerance.
If there are tolerance variations, the affected components (wheel bearing/drive unit flange) are to be
measured individually.
Nominal values for wheel bearing/drive unit flange: 72.47 mm - 72.50 mm (calliper gauge measuring
equipment )
If a component is not in the specification, contact technical support.
Have the following data ready.
- Tyre size:
- Tyre manufacturer:
- DOT:
- Rim styling
- Rim manufacturer (on the back):