Motorcycles are already covered by the rules. I made a suggestion about using Motorcycles for a recon squad in this thread:viewtopic.php?f=9&t=99
Another option could be to take a single Motorcycle with sidecar as a replacement for a HMG team, trading protection for speed.
Most German OOBs allow two HMG teams, meaning you could take two Motorcycle combinations this way.
The Warlord model is indeed nice. You might want to look at the Black Tree Design ones as well, they come with 3 riders each.