Derek, over on the GL1800 boards there is a special topic board for the darksiders so it isn't just one web site.
Not a fan of car tires on bikes personally but there is a fellow who does Turbo kits for the gold wing, $10,000 plus install, and he says he has put 50,000 onto his rear
tire while doing extensive testing of the acceleration properties of the turbo.....in the 1/4 mile head to head with a non turbo he says he is 300 feet ahead at the end.
I think if I was running a lot of miles I would at least try a car tire....they do look funny though....
I know it's not just one web site, and if they roll like that it's a place I don't belong.
I don't know about Darksiding yet, haven't tried it. Might not if I don't end up keeping the ZG.
I've got to decide once I get her back on the road.
My next bike won't be appropriate for a darkside setup, that much I know.