Hi, as a complete code and electronics newbie, I have started a project that I consider to be quite ambitious. Thanks to the great forum I am fighting my way through bit by bit.
I think i already have the answer to my question but i need help to write this line of code.

I want to adress the I2C pins 24, 25. I know I have to use Wire2 and I also got it to work with the scanner sketch.
If I want to implement the BNO055 Sensor in my main sketch (to get orientation) by writing Wire2.begin(); it isnt working.

In another old thread, Paul suggested that maybe the library of a sensor uses only wire.begin and so coding wire2 wont help.
In the Library of the BNO055 I found some words "Wire" but they are coded in a way I cant read.. (Adafruit_BNO055(int32_t sensorID = -1, uint8_t address = BNO055_ADDRESS_A,
TwoWire *theWire = &Wire)
What do I have to code to make the wire2 work with the Sensor library if that is indeed my problem?

Thanks in advance for the help!

Code:
/*!
 *  @file Adafruit_BNO055.h
 *
 *  This is a library for the BNO055 orientation sensor
 *
 *  Designed specifically to work with the Adafruit BNO055 Breakout.
 *
 *  Pick one up today in the adafruit shop!
 *  ------> https://www.adafruit.com/product/2472
 *
 *  These sensors use I2C to communicate, 2 pins are required to interface.
 *
 *  Adafruit invests time and resources providing this open source code,
 *  please support Adafruit andopen-source hardware by purchasing products
 *  from Adafruit!
 *
 *  K.Townsend (Adafruit Industries)
 *
 *  MIT license, all text above must be included in any redistribution
 */

#ifndef __ADAFRUIT_BNO055_H__
#define __ADAFRUIT_BNO055_H__

#include "Arduino.h"
#include <Wire.h>

#include "utility/imumaths.h"
#include <Adafruit_Sensor.h>

/** BNO055 Address A **/
#define BNO055_ADDRESS_A (0x28)
/** BNO055 Address B **/
#define BNO055_ADDRESS_B (0x29)
/** BNO055 ID **/
#define BNO055_ID (0xA0)

/** Offsets registers **/
#define NUM_BNO055_OFFSET_REGISTERS (22)

/** A structure to represent offsets **/
typedef struct {
  int16_t accel_offset_x; /**< x acceleration offset */
  int16_t accel_offset_y; /**< y acceleration offset */
  int16_t accel_offset_z; /**< z acceleration offset */

  int16_t mag_offset_x; /**< x magnetometer offset */
  int16_t mag_offset_y; /**< y magnetometer offset */
  int16_t mag_offset_z; /**< z magnetometer offset */

  int16_t gyro_offset_x; /**< x gyroscrope offset */
  int16_t gyro_offset_y; /**< y gyroscrope offset */
  int16_t gyro_offset_z; /**< z gyroscrope offset */

  int16_t accel_radius; /**< acceleration radius */

  int16_t mag_radius; /**< magnetometer radius */
} adafruit_bno055_offsets_t;

/*!
 *  @brief  Class that stores state and functions for interacting with
 *          BNO055 Sensor
 */
class Adafruit_BNO055 : public Adafruit_Sensor {
public:
  /** BNO055 Registers **/
  typedef enum {
    /* Page id register definition */
    BNO055_PAGE_ID_ADDR = 0X07,

    /* PAGE0 REGISTER DEFINITION START*/
    BNO055_CHIP_ID_ADDR = 0x00,
    BNO055_ACCEL_REV_ID_ADDR = 0x01,
    BNO055_MAG_REV_ID_ADDR = 0x02,
    BNO055_GYRO_REV_ID_ADDR = 0x03,
    BNO055_SW_REV_ID_LSB_ADDR = 0x04,
    BNO055_SW_REV_ID_MSB_ADDR = 0x05,
    BNO055_BL_REV_ID_ADDR = 0X06,

    /* Accel data register */
    BNO055_ACCEL_DATA_X_LSB_ADDR = 0X08,
    BNO055_ACCEL_DATA_X_MSB_ADDR = 0X09,
    BNO055_ACCEL_DATA_Y_LSB_ADDR = 0X0A,
    BNO055_ACCEL_DATA_Y_MSB_ADDR = 0X0B,
    BNO055_ACCEL_DATA_Z_LSB_ADDR = 0X0C,
    BNO055_ACCEL_DATA_Z_MSB_ADDR = 0X0D,

    /* Mag data register */
    BNO055_MAG_DATA_X_LSB_ADDR = 0X0E,
    BNO055_MAG_DATA_X_MSB_ADDR = 0X0F,
    BNO055_MAG_DATA_Y_LSB_ADDR = 0X10,
    BNO055_MAG_DATA_Y_MSB_ADDR = 0X11,
    BNO055_MAG_DATA_Z_LSB_ADDR = 0X12,
    BNO055_MAG_DATA_Z_MSB_ADDR = 0X13,

    /* Gyro data registers */
    BNO055_GYRO_DATA_X_LSB_ADDR = 0X14,
    BNO055_GYRO_DATA_X_MSB_ADDR = 0X15,
    BNO055_GYRO_DATA_Y_LSB_ADDR = 0X16,
    BNO055_GYRO_DATA_Y_MSB_ADDR = 0X17,
    BNO055_GYRO_DATA_Z_LSB_ADDR = 0X18,
    BNO055_GYRO_DATA_Z_MSB_ADDR = 0X19,

    /* Euler data registers */
    BNO055_EULER_H_LSB_ADDR = 0X1A,
    BNO055_EULER_H_MSB_ADDR = 0X1B,
    BNO055_EULER_R_LSB_ADDR = 0X1C,
    BNO055_EULER_R_MSB_ADDR = 0X1D,
    BNO055_EULER_P_LSB_ADDR = 0X1E,
    BNO055_EULER_P_MSB_ADDR = 0X1F,

    /* Quaternion data registers */
    BNO055_QUATERNION_DATA_W_LSB_ADDR = 0X20,
    BNO055_QUATERNION_DATA_W_MSB_ADDR = 0X21,
    BNO055_QUATERNION_DATA_X_LSB_ADDR = 0X22,
    BNO055_QUATERNION_DATA_X_MSB_ADDR = 0X23,
    BNO055_QUATERNION_DATA_Y_LSB_ADDR = 0X24,
    BNO055_QUATERNION_DATA_Y_MSB_ADDR = 0X25,
    BNO055_QUATERNION_DATA_Z_LSB_ADDR = 0X26,
    BNO055_QUATERNION_DATA_Z_MSB_ADDR = 0X27,

    /* Linear acceleration data registers */
    BNO055_LINEAR_ACCEL_DATA_X_LSB_ADDR = 0X28,
    BNO055_LINEAR_ACCEL_DATA_X_MSB_ADDR = 0X29,
    BNO055_LINEAR_ACCEL_DATA_Y_LSB_ADDR = 0X2A,
    BNO055_LINEAR_ACCEL_DATA_Y_MSB_ADDR = 0X2B,
    BNO055_LINEAR_ACCEL_DATA_Z_LSB_ADDR = 0X2C,
    BNO055_LINEAR_ACCEL_DATA_Z_MSB_ADDR = 0X2D,

    /* Gravity data registers */
    BNO055_GRAVITY_DATA_X_LSB_ADDR = 0X2E,
    BNO055_GRAVITY_DATA_X_MSB_ADDR = 0X2F,
    BNO055_GRAVITY_DATA_Y_LSB_ADDR = 0X30,
    BNO055_GRAVITY_DATA_Y_MSB_ADDR = 0X31,
    BNO055_GRAVITY_DATA_Z_LSB_ADDR = 0X32,
    BNO055_GRAVITY_DATA_Z_MSB_ADDR = 0X33,

    /* Temperature data register */
    BNO055_TEMP_ADDR = 0X34,

    /* Status registers */
    BNO055_CALIB_STAT_ADDR = 0X35,
    BNO055_SELFTEST_RESULT_ADDR = 0X36,
    BNO055_INTR_STAT_ADDR = 0X37,

    BNO055_SYS_CLK_STAT_ADDR = 0X38,
    BNO055_SYS_STAT_ADDR = 0X39,
    BNO055_SYS_ERR_ADDR = 0X3A,

    /* Unit selection register */
    BNO055_UNIT_SEL_ADDR = 0X3B,
    BNO055_DATA_SELECT_ADDR = 0X3C,

    /* Mode registers */
    BNO055_OPR_MODE_ADDR = 0X3D,
    BNO055_PWR_MODE_ADDR = 0X3E,

    BNO055_SYS_TRIGGER_ADDR = 0X3F,
    BNO055_TEMP_SOURCE_ADDR = 0X40,

    /* Axis remap registers */
    BNO055_AXIS_MAP_CONFIG_ADDR = 0X41,
    BNO055_AXIS_MAP_SIGN_ADDR = 0X42,

    /* SIC registers */
    BNO055_SIC_MATRIX_0_LSB_ADDR = 0X43,
    BNO055_SIC_MATRIX_0_MSB_ADDR = 0X44,
    BNO055_SIC_MATRIX_1_LSB_ADDR = 0X45,
    BNO055_SIC_MATRIX_1_MSB_ADDR = 0X46,
    BNO055_SIC_MATRIX_2_LSB_ADDR = 0X47,
    BNO055_SIC_MATRIX_2_MSB_ADDR = 0X48,
    BNO055_SIC_MATRIX_3_LSB_ADDR = 0X49,
    BNO055_SIC_MATRIX_3_MSB_ADDR = 0X4A,
    BNO055_SIC_MATRIX_4_LSB_ADDR = 0X4B,
    BNO055_SIC_MATRIX_4_MSB_ADDR = 0X4C,
    BNO055_SIC_MATRIX_5_LSB_ADDR = 0X4D,
    BNO055_SIC_MATRIX_5_MSB_ADDR = 0X4E,
    BNO055_SIC_MATRIX_6_LSB_ADDR = 0X4F,
    BNO055_SIC_MATRIX_6_MSB_ADDR = 0X50,
    BNO055_SIC_MATRIX_7_LSB_ADDR = 0X51,
    BNO055_SIC_MATRIX_7_MSB_ADDR = 0X52,
    BNO055_SIC_MATRIX_8_LSB_ADDR = 0X53,
    BNO055_SIC_MATRIX_8_MSB_ADDR = 0X54,

    /* Accelerometer Offset registers */
    ACCEL_OFFSET_X_LSB_ADDR = 0X55,
    ACCEL_OFFSET_X_MSB_ADDR = 0X56,
    ACCEL_OFFSET_Y_LSB_ADDR = 0X57,
    ACCEL_OFFSET_Y_MSB_ADDR = 0X58,
    ACCEL_OFFSET_Z_LSB_ADDR = 0X59,
    ACCEL_OFFSET_Z_MSB_ADDR = 0X5A,

    /* Magnetometer Offset registers */
    MAG_OFFSET_X_LSB_ADDR = 0X5B,
    MAG_OFFSET_X_MSB_ADDR = 0X5C,
    MAG_OFFSET_Y_LSB_ADDR = 0X5D,
    MAG_OFFSET_Y_MSB_ADDR = 0X5E,
    MAG_OFFSET_Z_LSB_ADDR = 0X5F,
    MAG_OFFSET_Z_MSB_ADDR = 0X60,

    /* Gyroscope Offset register s*/
    GYRO_OFFSET_X_LSB_ADDR = 0X61,
    GYRO_OFFSET_X_MSB_ADDR = 0X62,
    GYRO_OFFSET_Y_LSB_ADDR = 0X63,
    GYRO_OFFSET_Y_MSB_ADDR = 0X64,
    GYRO_OFFSET_Z_LSB_ADDR = 0X65,
    GYRO_OFFSET_Z_MSB_ADDR = 0X66,

    /* Radius registers */
    ACCEL_RADIUS_LSB_ADDR = 0X67,
    ACCEL_RADIUS_MSB_ADDR = 0X68,
    MAG_RADIUS_LSB_ADDR = 0X69,
    MAG_RADIUS_MSB_ADDR = 0X6A
  } adafruit_bno055_reg_t;

  /** BNO055 power settings */
  typedef enum {
    POWER_MODE_NORMAL = 0X00,
    POWER_MODE_LOWPOWER = 0X01,
    POWER_MODE_SUSPEND = 0X02
  } adafruit_bno055_powermode_t;

  /** Operation mode settings **/
  typedef enum {
    OPERATION_MODE_CONFIG = 0X00,
    OPERATION_MODE_ACCONLY = 0X01,
    OPERATION_MODE_MAGONLY = 0X02,
    OPERATION_MODE_GYRONLY = 0X03,
    OPERATION_MODE_ACCMAG = 0X04,
    OPERATION_MODE_ACCGYRO = 0X05,
    OPERATION_MODE_MAGGYRO = 0X06,
    OPERATION_MODE_AMG = 0X07,
    OPERATION_MODE_IMUPLUS = 0X08,
    OPERATION_MODE_COMPASS = 0X09,
    OPERATION_MODE_M4G = 0X0A,
    OPERATION_MODE_NDOF_FMC_OFF = 0X0B,
    OPERATION_MODE_NDOF = 0X0C
  } adafruit_bno055_opmode_t;

  /** Remap settings **/
  typedef enum {
    REMAP_CONFIG_P0 = 0x21,
    REMAP_CONFIG_P1 = 0x24, // default
    REMAP_CONFIG_P2 = 0x24,
    REMAP_CONFIG_P3 = 0x21,
    REMAP_CONFIG_P4 = 0x24,
    REMAP_CONFIG_P5 = 0x21,
    REMAP_CONFIG_P6 = 0x21,
    REMAP_CONFIG_P7 = 0x24
  } adafruit_bno055_axis_remap_config_t;

  /** Remap Signs **/
  typedef enum {
    REMAP_SIGN_P0 = 0x04,
    REMAP_SIGN_P1 = 0x00, // default
    REMAP_SIGN_P2 = 0x06,
    REMAP_SIGN_P3 = 0x02,
    REMAP_SIGN_P4 = 0x03,
    REMAP_SIGN_P5 = 0x01,
    REMAP_SIGN_P6 = 0x07,
    REMAP_SIGN_P7 = 0x05
  } adafruit_bno055_axis_remap_sign_t;

  /** A structure to represent revisions **/
  typedef struct {
    uint8_t accel_rev; /**< acceleration rev */
    uint8_t mag_rev;   /**< magnetometer rev */
    uint8_t gyro_rev;  /**< gyroscrope rev */
    uint16_t sw_rev;   /**< SW rev */
    uint8_t bl_rev;    /**< bootloader rev */
  } adafruit_bno055_rev_info_t;

  /** Vector Mappings **/
  typedef enum {
    VECTOR_ACCELEROMETER = BNO055_ACCEL_DATA_X_LSB_ADDR,
    VECTOR_MAGNETOMETER = BNO055_MAG_DATA_X_LSB_ADDR,
    VECTOR_GYROSCOPE = BNO055_GYRO_DATA_X_LSB_ADDR,
    VECTOR_EULER = BNO055_EULER_H_LSB_ADDR,
    VECTOR_LINEARACCEL = BNO055_LINEAR_ACCEL_DATA_X_LSB_ADDR,
    VECTOR_GRAVITY = BNO055_GRAVITY_DATA_X_LSB_ADDR
  } adafruit_vector_type_t;

  Adafruit_BNO055(int32_t sensorID = -1, uint8_t address = BNO055_ADDRESS_A,
                  TwoWire *theWire = &Wire);

  bool begin(adafruit_bno055_opmode_t mode = OPERATION_MODE_NDOF);
  void setMode(adafruit_bno055_opmode_t mode);
  void setAxisRemap(adafruit_bno055_axis_remap_config_t remapcode);
  void setAxisSign(adafruit_bno055_axis_remap_sign_t remapsign);
  void getRevInfo(adafruit_bno055_rev_info_t *);
  void setExtCrystalUse(boolean usextal);
  void getSystemStatus(uint8_t *system_status, uint8_t *self_test_result,
                       uint8_t *system_error);
  void getCalibration(uint8_t *system, uint8_t *gyro, uint8_t *accel,
                      uint8_t *mag);

  imu::Vector<3> getVector(adafruit_vector_type_t vector_type);
  imu::Quaternion getQuat();
  int8_t getTemp();

  /* Adafruit_Sensor implementation */
  bool getEvent(sensors_event_t *);
  bool getEvent(sensors_event_t *, adafruit_vector_type_t);
  void getSensor(sensor_t *);

  /* Functions to deal with raw calibration data */
  bool getSensorOffsets(uint8_t *calibData);
  bool getSensorOffsets(adafruit_bno055_offsets_t &offsets_type);
  void setSensorOffsets(const uint8_t *calibData);
  void setSensorOffsets(const adafruit_bno055_offsets_t &offsets_type);
  bool isFullyCalibrated();

  /* Power managments functions */
  void enterSuspendMode();
  void enterNormalMode();

private:
  byte read8(adafruit_bno055_reg_t);
  bool readLen(adafruit_bno055_reg_t, byte *buffer, uint8_t len);
  bool write8(adafruit_bno055_reg_t, byte value);

  uint8_t _address;
  TwoWire *_wire;

  int32_t _sensorID;
  adafruit_bno055_opmode_t _mode;
};

#endif
P.S. If there is an audio enthusiast among you that I could ask some basic questions about my project, I would be very grateful. I understand that specific problems are easier to solve, but maybe I could avoid a lot of them this way!