Yamaha mounted Andrea Bartolini of Italy won both races at the Motocross World Championship 500 Grand Prix held in Luxembourg on August 8, 1999. The results of the two heats are as follows:
Results of Heat No. 1:
- Andrea Bartolini #5 (Yamaha)
- Bernd Eckenbach #4 (Husqvarna)
- Peter Johansson #3 (KTM)
- Francisco Garcia Vico #68 (Yamaha)
- Yves Demaria #110 (Husqvarna)
- Massimo Bartolini #56 (Honda)
- Jochen Jasinski #14 (Honda)
- Trampas Parker #171 (KTM)
- Miska Aaltonen #23 (Yamaha)
- Robert Herring #7 (Honda)
Results of Heat No. 2:
- Andrea Bartolini #5 (Yamaha)
- Francisco Garcia Vico #68 (Yamaha)
- Jochen Jasinski #14 (Honda)
- Peter Johansson #3 (KTM)
- Bernd Eckenbach #4 (Husqvarna)
- Shayne King #8 (KTM)
- Robert Herring #7 (Honda)
- Willie van Wessel #8 (Husqvarna)
- Alessandro Puzar #55 (Yamaha)
- Erwin Machtlinger #9 (Honda)
Chiodi and Federici Win 125 MX GP Heats in Switzerland
Alessio Chiodi on a Husqvarna and Claudio Federici on a Yamaha won the first and second heats, respectively, at the Motocross World Championship 125 Grand Prix held in Switzerland on August 8, 1999. The results of the two heats are as follows:
Results of Heat No. 1:
- Alessio Chiodi #1 (Husqvarna)
- Mike Brown #100 (Honda)
- Patrick Caps #23 (Honda)
- Thomas Traversini #19 (Husqvarna)
- Claudio Federici #4 (Yamaha)
- Steve Ramon #26 (Kawasaki)
- James Dobb #9 (Suzuki)
- Grant Langston #35 (KTM)
- Matthieu Lalloz #28 (Yamaha)
- Luigi Seguy #5 (Honda)
Results of Heat No. 2:
- Claudio Federici #4 (Yamaha)
- Mike Brown #100 (Honda)
- Alessio Chiodi #1 (Husqvarna)
- Carl Nunn #7 (Yamaha)
- Luigi Seguy #5 (Honda)
- Grant Langston #35 (KTM)
- James Dobb #9 (Suzuki)
- Patrick Caps #23 (Honda)
- Matthew Lalloz #28 (Yamaha)
- Thomas Traversini #19 (Husqvarna)