King's Lynn Stars have signed World Under-21 champion Maciej Janowski, while Daniel Nermark has returned to the Norfolk Arena.
The addition of 20-year-old Pole Janowski, who rode at Swindon last season, and Swede Nermark, 34, completes the Stars line-up for 2012.
"It's a big coup for the club to get a rider of Maciej's quality," boss Rob Lyon told BBC Radio Norfolk.
"Signing riders of that nature is a gamble, but it's a calculated gamble."
Fillip Sitera and Michael P Toft will make up the numbers by sharing a reserve berth.
The current line-up exceeds the Elite League's 41-point average limit, but King's Lynn management expect that to drop when Wolbert's average decreases from 5.17 to an estimated 4.28 after two away meetings.
Lyon, whose side reached the play-off semi-finals in 2011, added: "We'd like to go a little bit further. We'd like to get into the final and maybe win it.
"I feel with the team we've put together there's enough quality to reach the play-offs."