Zack started racing BMX at 3 years old and is sponsored by BMX giant Crupi Racing .
Zack Walker secured his 10th win in the 5 and under novice class to move up to intermediate class last Monday .
Zack Walker started racing BMX at 3 years old and is sponsored by BMX giant Crupi Racing .
Zack Walker secured his 10th win in the 5 and under novice class to move up to intermediate class last Monday .