While attending Sousa High School in Chiba, majoring in English, he started to fully participate in the 125cc class of All Japan Road Race Championship and gained 2nd place for 2006 season.

Upon his high school graduation in March 2009, Tomizawa was recruited by new CIPMOTO-GP250 Team, ended his full-time, first international racing year in 17th place with best results at 10th twice at Motegi and Valencia respectively riding a Honda RS250R.

Riding a Suter motorbike, he won the inaugural Moto2 race at Losail, and followed this up with his first Grand Prix pole position and second place at the following round in Spain.

On lap 12, holding 4th place, Tomizawa fell at the Curvone, a fast right-hand corner, when he was forced wide and lost grip in his rear tire.

[11] Alex Hofmann originally reported on German TV that neither Tomizawa nor Redding had suffered life-threatening injuries; he had apparently received this information from Dorna themselves.

It was reported that Rimini's state prosecutor, Paolo Giovagnoli, would begin an inquest that might involve criminal proceedings against as yet unnamed individuals.