There several ways to change the tempo in Logic. If you want to change the tempo of your track globally, the easiest way is to double-click the tempo in the Transport Bar and enter a new value.
However, if you need to use multiple tempos in the same project, you can use the Tempo Track or the Tempo List (and even more options are available... but these are the 2 main ways).
[b]Using the Tempo Track:
1. Choose View > Global Track (or simply press G on your keyboard)
2. Open the Tempo track by clicking on the disclosure triangle
3. Make sure you have the Pointer tool selected
4. Control-Option-Command-click at the bar you want to change the tempo (do not click-hold... but hold down the 3 keys and click)
5. Enter the new tempo value and press Return. Please note this will change the tempo of you project at the bar where you inserted the new tempo. This will not change the BPM of your track at the beginning of you project.
[b]Using the Tempo List:
1. Go to Options > Tempo > Open Tempo list
2. Click the Create button to insert a tempo change
3. Change the Position value (choose the bar where you want the tempo change to occur)
4. Insert a new tempo