I thought they were hydraulic, I was wrong.
THE BASICS OF AWD
Christiniís patented mechanical All Wheel Drive system delivers power from the motorcycle transmission to the front wheel through a series of chains and shafts. There is no energy-robbing hydraulics involved.
The lightweight all-mechanical system works similar to that of AWD systems found on four wheeled vehicles. The AWD system (powering the front wheel) is driven at a slightly lower rate than the rear wheel (approximately 80%). Under optimum traction conditions, the rear wheel is actually driving faster than the front AWD system. One-way clutches within the front hub allow the front wheel to freewheel under these conditions. At this point, the AWD system is effectively passive. Though the front AWD system is turning, it is not actually transferring power to the front wheel. When the rear wheel loses traction, the drive ratio, relative to your forward speed, changes. The AWD system engages, transferring power to the front wheel until traction is reestablished at the rear wheel.
CJ Racer here on Adv built a 990 AWD form Christini parts