Currently MonsterGy6 is the only company that offers Hubs and Short axles for the 50cc Maddog. Their kit allows you to run a 12×8 wheel completely centered with a safe short axle. MonsterGy6 states that a 12×8 wheel is the only way to run it centered so they do not offer 12×7 wheels for a stock Maddog 50cc

If you want to go Single Shock this is the recommended way to do so.