Board Thread:Questions and Answers/@comment-90.210.127.4-20140315132133/@comment-15636815-20140316044304

To receive a set bonus, the locomotive and all wagons in the train must belong to the same set.


 * This DOES NOT mean that you must have every type of wagon available for the set.
 * This DOES NOT mean that you must fill the locomotive to its maximum power.
 * This DOES mean that non-set wagons in the train will prevent the set bonus.

Examples:
 * Shamrock + 50 wagons from Shamrock (Set) ==> set bonus
 * Shamrock + 40 wagons from Shamrock (Set) ==> set bonus
 * Shamrock + 49 wagons from Shamrock (Set) + 1 other wagon ==> NO set bonus

Hope this helps.