Copying 1 to 2: 8.97
Copying 2 to 3: 7.36
Copying 3 to 4: 7.08
Copying 4 to 5: 6.51
Copying 5 to 6: 6.92
Copying 6 to 7: 7.33
Copying 7 to 8: 7.86
Copying 8 to 9: 8.00
Copying 9 to 10: 11.07
Copying 10 to 11: 10.39
Copying 11 to 12: 16.46
Copying 12 to 13: 56.50
Copying 13 to 14: 233.98
Results with modified method including sync on 32bit. Will repeat with 64bit live CD tomorrow evening.
16.04.2 LTS (Xenial Xerus), 4.8.0-54-generic, i386, RAM=16552604
Copying 1 to 2: 8.97
Copying 2 to 3: 7.36
Copying 3 to 4: 7.08
Copying 4 to 5: 6.51
Copying 5 to 6: 6.92
Copying 6 to 7: 7.33
Copying 7 to 8: 7.86
Copying 8 to 9: 8.00
Copying 9 to 10: 11.07
Copying 10 to 11: 10.39
Copying 11 to 12: 16.46
Copying 12 to 13: 56.50
Copying 13 to 14: 233.98