Thank you for your detailed feedback.
We are sorry that the external TPMS sensor did not fully meet your expectations on your BMW S1000XR 2015.
Our external TPMS sensors are designed to fit most motorcycle wheels, but they are not specifically developed for each BMW model. On some motorcycles, the space between the valve and the brake caliper can be very limited, as in your case.
If the clearance is only around 2 mm, we recommend being very careful and not using the external sensor if you feel there is any risk of contact with the brake caliper while riding.
We also understand your suggestion about an internal sensor similar to the BMW Schrader system. We do offer internal TPMS sensors as an alternative, which you may consider if you prefer a more discreet installation and better clearance for this type of wheel setup.
Thank you again for your feedback.
Best regards,