I wouldn't bother, apparentely 90% of people quit before the end of the race if they know they're going to lose so they don't have high losing stats. wwwww
If you quit before all four races are over, you automatically get a loss, so it's more about not wasting your time than stats. In my experience it's more like 20% that disconnect.As has been suggested, enter your information manually by going to Nintendo WFC > Nintendo WFC Settings > Nintendo Wi-Fi Connection Settings > Connection 1
Here are my settings, adjust to match your info
Auto Obtain IP - No
IP Address - 192.168.2.2
Subnet Mask 255.255.255.0
Gateway (Router IP): 192.168.2.1
Auto-obtain DNS - No
Primary - Use yours
Secondary - 0.0.0.0
Then try "Test Connection"
Also enable virtual DMZ in your router settings. Gateway IP can be found from cmd > ipconfig.