Ervik's best distance is traditionally the 5000-m, where he for several years was among the very best of the world, but his top priority for the most part of his career was to perform optimally in the allround championships.

Under American coach Peter Mueller, Ervik enjoyed a new spring as a speed skater – on 15 October 2005, he set a new world outdoor record on the 3000 meters, finishing at 3:44.90 in Inzell, and on 5 November 2005, he set the world record (indoor or outdoor) on that distance in Calgary with a time of 3:37.28.

Ervik's highest ranking on the all-time best-ever Adelskalender list was a 4th place, a position he held briefly on 4 December 2005, when he became the second skater ever to race a 10,000-m below 13 minutes (but 12.52 seconds later Enrico Fabris overtook his 4th rank position).

Due to the car's traction and handling being reduced to virtually zero while on the ice, Ervik managed to finish the race with a two lap lead.

Ervik currently works as head of the marketing department at the Storhamar Dragons front office.