In the 1989 All Japan Motocross season, Atsushi Okabe took the 250cc class championship aboard his KX250SR. Instead of a single backbone frame – the norm at the time – it had two square pipes that ran around the tank: the first perimeter frame. The epoch-making feature was typical of Kawasaki, known for pioneering new technology in the motocross industry. Adding to the sensation, the bike won in its first season. The perimeter frames featured on the 1990 mass-production KX250 and KX125 models the following year became the basis for the aluminium perimeter frames used today.