"I was disappointed [not to be renewed with team Garmin], but it also opened new doors," Dekker told The Netherlands' AD newspaper.
"I'm not done with cycling. I could race for a small Italian small team, but that would do nothing for me. The attack on the world record is something else. It's ambitious, and it's all or nothing."
The 30-year-old won the 2006 Tirreno-Adriatico and 2007 Tour de Romandie before sitting out due to an EPO doping ban. He returned to race the last four years with American team Garmin-Sharp.
He has yet to set a date to attempt to break the mark that IAM Cycling's Austrian, Matthias Brändle set on October 30.
Dekker's attempt will be part of wave of attempts and plans since the UCI changed the rules on May 15 to allow pursuit track-style bikes.
Following the change, on September 18, German Jens Voigt (Trek Factory Racing) retired by being the first to attempt and set a new mark at 51.110 kilometres. Brändle announced his attempt and broke the record soon after.
Along with Dekker, Briton Alex Dowsett (Movistar), Dane Alex Rasmussen and American Taylor Phinney (BMC Racing) have shown interest in taking on cycling's revived blue riband event ahead of the 2015 season. Sky's Bradley Wiggins could set a mark that will stand for several years when rides as planned this June or July.
"It will be one of the toughest trials of my life, but that does not matter to me. I'm not afraid of it," Dekker said.
"I put everything aside in the next few months. I put everything I have into that one hour. I'm going to make it? Yes, of course, I'm going to get it."
After his return from a doping ban, Dekker struggled to find his place in cycling. He helped Garmin's leaders, had a chance to race for himself and won a stage in the Circuit Cycliste Sarthe.
In recent long time trials, he placed 131st over 47.2km in the 2014 Giro d'Italia, 23rd over 37km in the 2013 Tour of Poland and 136th over 54.8km in the 2013 Giro. The hour record distance is all that matters now for Dekker, who said that he is unsure if he will race afterwards.
"It could be my last trick. Maybe I'll stop it with the world record in my pocket. I might continue, but I'll see in the coming months," Dekker added. "I'm only concerned with that one day alone for now."
More on the Hour Record
Former Hour Record holder Ole Ritter thinks Bradley Wiggins could hit the 55-kilometre mark for the iconic record
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