What electronics are you using? RPi, Arduino, MicroPython?
Not exactly sure what you mean by "combined motion". Assuming this means sensor fusion, here's an example of a 3 axis accelerometer + 2 axis gyro with complementary filter to accurately estimate 3 axis orientation http://www.starlino.com/imu_guide.html
which people have used to build self balancing robots (comment section from above link has people building them too). Basically, you use both the accel and gyro to get a more accurate orientation estimate than either alone. Then, orientation is fed into your system model to balance the bike. You can also add a gps if you need to track position.
Prerequisites are trig. and basic feedback control. There should be plenty of programming help online for your sensors, though I'd recommend Arduino if you haven't coded much.