I personally can't wait to find out about the quarter-inching valve, but here's how the one-inching valve works on my
L2800.
It has a standard position type lever with float at the far forward position and all the way up at the rear position. The total travel of the handle on the lever is probably eight inches or so. I'm at work right now or I'd post a photo of the lever for you.
If you start with the lever all the way back (arms up) and then push it forward a little bit, the arms will fall a little bit. If you push it forward further, it will fall more. In general, this action is in one-inch increments, but down travel speed is controlled by the knob near the front of the seat. You get the feeling that you have decent control going down because of the speed adjustment.
On the other hand, if you pull the lever toward the rear, nothing will happen until you pull it far enough for the valve to get to the next increment. You know when you get to the next increment because the arms then rise one inch. Suddenly. With full force. No feathering, no force adjustment. One inch at the arms means about six inches at the tail wheel of a five foot mower, by the way, and when that baby jumps, the whole tractor does. That's the source of complaints with the one-inch valve that Kubota will replace.
I presume that the quarter-inch valve will work in the same way except that 1) it moves in quarter-inch increments instead of one inch, and 2) I hear that it feathers better rather than just jumping to the next increment all of a sudden (in other words, a proportional indexing valve).
At least I hope #2 is true, and as soon as my dealer gets the part, I'll know for sure.
Obviously, someone with actual experience with the quarter-inch valve could tell us for sure about the action of the lever.
- Just Gary