Talmácsi had his first full Grand Prix season in 2001, with the Racing Service team, on a private Honda RS125R bike.

The change wasn't a real success with no points in five races, and during the 2002 season, Talmácsi switched to the PEV ADAC Sachsen team, where he could ride a Honda again.

In 2003 he signed for the reigning world champion Exalt Cycle Aprilia team, to partner teammate Steve Jenkner.

Although not challenging for wins like his teammate, Talmácsi still had a much improved year, with consistent top-10 finishes (seven times), and a career high 70 points in the championship, which was good enough for 14th overall.

He finished 17th in the championship with 43 points, and his results with a weaker bike attracted the attention of teams like Derbi, Gilera, Honda and KTM.

Joining the Red Bull KTM team for 2005 gave Talmácsi the real breakthrough year, scoring his career's maiden podium in the third race of the season at Shanghai.

Two races later in Mugello, he inherited his first victory, after a last lap fall from KTM teammate Mika Kallio and Héctor Faubel saw him cross the finish line first.

Talmácsi managed a season's best finish of 3rd in Brno, the closest race to a "home" Grand Prix, but that was the most he could get out of his bike.

Coming into his 7th season of the 125cc category, he was given an offer from Jorge "Aspar" Martínez's team to ride one of their bikes in 2007, replacing outgoing world champion Bautista.

In Barcelona his two main rivals at the time, Faubel and Pešek, crashed into each other while Talmácsi finished 2nd, again leading the world championship by 13 points.

The last race of the season at Valencia saw Talmácsi come into the weekend with a 10-point advantage, and needed to finish on the podium if Faubel won.

Talmácsi started from pole, and in an absolutely tense race where Faubel tried everything, including backing them up into fellow Spanish Aspar Aprilia rider Sergio Gadea, but Talmácsi hung on to second place (third still would have been enough by one point if Gadea passed him), finishing just behind his rival race-winner Faubel, and became the 2007 125cc World Champion.

The party to celebrate his success back in Budapest, Hungary was known as "Talmageddon", a word play between Talmácsi and Armageddon, and was also named 2007 Hungarian Sportsman of the Year for his achievements.

Talmácsi started the 2009 season in the 250cc class, but left Aspar's Balatonring Team after only three races following a row over image rights, firing his manager Stefano Favaro in the process as well.

His best result was 12th in Donington, finishing ahead of notable riders Chris Vermeulen, Casey Stoner and Nicky Hayden in wet conditions.

Talmácsi accepted, and had an okay season, scoring regular high point finishes, but only stood on the podium once, a 3rd place in Aragón.

According to Favaro, Talmácsi had another contract offer which he declined in December 2010, which was a big mistake, as at age 30, he couldn't afford to miss a full season.

[8] "My doctor explained what has happened to my leg, it is basically as if it had been fired at from close range with a pistol, the engine block exploded with such force.

[9] He announced his retirement from motorcycle racing following the incident, no longer having the necessary strength in his legs to perform at an elite level.