|Morgan Dual Drive|
This is the 2004 release from Morgan Forestry. It represents a significant redesign from the earlier models that we have. Morgan has abandoned the steering which is a feature of our models in favor of a tandem drive. The steering while nice presented some design compromises. By eliminating the steering it was possible to make the body wider (tire clearance issues). This resolved a nagging issue relating to ease of access. It also provided space internally to drop the engine clear down to the belly of the machine lowering the center of gravity significantly. In Mechanical drive machines the location of the engine and the transmission is driven by needs for drive line alignment, but with a hydrostatic drive no such constraints exist. Likewise the engine does not conflict with the front axle, so down between the tires the engine goes. The rear unit sports a tandem drive with hydrostatic motors on each side. The drive unit itself is the same one used on other logging equipment with tandem drives often made in Europe, but instead of being mechanically turned it has a hydrostatic drive.
The tandem drive provide more traction for difficult conditions and as with forwarders and other machines with this tandem drive there are tracks that slip over the tires. Reports are that this machine is consistently more productive than a Cat 527 track skidder.
One of the good features of the hydrostatic drive is that the torque roll comes out as a benefit instead of a detriment. On a mechanical drive machine the torque roll is trying to lift the front of the machine and puts disproportionate weight on the front axle of the tandem drive---always making it more difficult for it to climb over things. Because the hydraulic motor is attached to the walking beam and not the main frame, the torque roll of the the Morgan is trying to lift the front of the walking beam instead of the front of the machine. This means that the front tire of the tandem drive runs light and therefore likes to climb over things----a real good thing. If you can get the front wheel up on top instead of jammed under, the rear tire is likely to follow.