Combines hyd rotor drive

Why in earth would you want a hydraulic drive on the rotor, Other than possibility of backing out a wad, increased cost, (hydro drive able to hold more than 300 hp or in case of the big combines 500 hp) more fuel consumption (add 20 to 30%),less power, more heat. You still need a gear box, so what have you eliminated, a mainshaft and a couple of beltsIJ You know why the massey's came out with the XP versions Xtra power is because the first ones were to gutless because of the power loss in the hydraulic coupling.

I think CIH is using a CVT transmission to run the rotor on the 8010 which is much more efficient than a straight hydrostat. I suspect that will be the way of the future. Tough to put all that horsepower new combines have through a varie-drive belt arrangement too.

The hydraulic drive is the best thing going on a combine.Simple reliable and no it does not take a lot more fuel and power. Anybody that has one or drives one will tell you this.

I demoed a 9790 along side an R 75. The 9790 had constant rotor speed which would keep the rotor running at optimum speed at all times. Im not sure if the technology is there to do it with variable drives, but let me tell ya it makes a difference to keep that rotor spinning the rpms it is supposed too. The 9790 never lacked any horsepower and fuel consumption wasnt anymore. of course they were different engines but the horsepower was about the same. I like the idea of the hydraulic drive rotor, just not sure how they would mount that on a transverse rotor and the system they have works pretty darn well. If it aint broke dont fix it.

I agree, hydraulic drives up at this horsepower range are ridiculously expensive and inefficient. The factory Gleaner set up seems to work great. It seems to be much more reliable than anyone elses drive. This is probably the last place on the combine I would make changes. And yes,Massey tried it and it didn't work, but I'm not sure that their system was governed to hold a set speed.

Guess what the R75 has constant rotor speed because it is driven by mechanical drives, this is a option they have to advertise because they are hydraulic drive. They added a govener to the hydraulic drive to match flow and pressure to load. You have that already on your injection pump. When you walk into hydraulic shop with your dead hydrostatic drive remind them how simple it is and remember that when they had you the bill for 20 K. Do you see any 500 hp tractors with hydrostatic driveIJ Cvt would be the way to go but then the cost of these machines is already nuts, I would like to see that driving the wheels.

When your engine comes under excessive load, the rotor does slow down quite abit, watch your rotor rpm readout. The constant rotor speed has the ability to increase rotor speed as engine speed decrease. Also yes you will see the CVT transmission in 500 hp tractors and more. The CVT is much simpler than any mechanical or powershift transmission and Im not talking about the IVT I am talking about the Fendt CVT.

Anyone who has been around a machine with hyd. rotor drive will tell you how great it is. We are on our sixth Massey rotary with hyd. rotor drive. We have never had any problems at all with the hydraulic system on these combines. I wouldn't say that any of the machines were under powered. We ran a 25' platform in beans with our 8570's and it handled it just fine. We have ran 30' platforms on our 8780's and they have all had ample power as well. The extra power on our current 8780XP is nice but I would say that the constant rotor speed control introduced on the early 8780's was more beneficial than the extra power on the XP's. The rotor speed stays constant and will not drop. IT will actually increase a little when a wad goes through the rotor. This helps tremendously in tough green soybeans. We did have to reverse the rotor on the 8570's a few times because of a plug. But I don't believe we have ever had to use the reverser on the 8780's with the constant speed rotor.

I guess we would all be better off with varible speed standard shift combines too instead of hydrostatic..rightIJ