kubota vs. kioti

[sawtooth]

No I have not tried it. BUT one would assume a new 5' cutter with much smaller gearbox vs a older Bush Hog 6' 286 with a MUCH larger box wouldn't even be a comparison. To be honest I'm not sure the Jubilee could even pick it up. I can try it though and just leave it on ground. Will report back soon.

 

[SPYDERLK]

No I have not tried it. BUT one would assume a new 5' cutter with much smaller gearbox vs a older Bush Hog 6' 286 with a MUCH larger box wouldn't even be a comparison. To be honest I'm not sure the Jubilee could even pick it up. I can try it though and just leave it on ground. Will report back soon.

The 5' on the larger tractor would be a valid check to see if the poor performance goes with it. Does the gearbox heat up much?.

 

[k0ua]

If you could do a double blind test (swap cutters) test and report back it would be educational.

 

[sawtooth]

The fact that it us a diesel has nothing to do with it. The 2810 is only 32 PTO HP vs 30 for the naa. The NCAA has more torque though. 110@ 1400rpm vs the 2810 having 101ft-lbs also at 1400. I agree with James that it isn't a good comparison. You need the same cutter on both. But its funny how you said the one with more power (but less torque) pulls the cutter better.

That is strange. I would have guessed the 2810 had more torque for sure. By seeing them both run I will be amazed if the 2810 won't cut in a pretty high gear with the 5 footer. Maybe I'm wrong though. Anyone else have a NAA / Jubilee and ran a 6' hog with? If so how does it do? Compression checked out good good and oil pressure is great. But in first gear I run it wide open in the thick heavy grass and it's about all it can do to keep up. Doing the test will be interesting.

 

[94BULLITT]

No I have not tried it. BUT one would assume a new 5' cutter with much smaller gearbox vs a older Bush Hog 6' 286 with a MUCH larger box wouldn't even be a comparison. To be honest I'm not sure the Jubilee could even pick it up. I can try it though and just leave it on ground. Will report back soon.

A 8N will run a 5' hog. Something is wrong with the Jubilee or your hog or the grass is super thick.

 

[tomato coupe]

How fast can a 4400 lb (2000 kg) tractor go up a 30 degree incline powered by an engine with performance shown in the attached graph? The graph is for a an actual Kubota engine that produces 50 hp (@2700 RPM) and 110 lb-ft of torque (@1600 RPM). Let's assume the tractor has a 12 speed, geared transmission that can cover the range of 1-12 mph, and it is lossless. Let's also assume that road friction is negligible.

1. The work performed is equal to m * g * h, where m is the mass of the tractor, g is the acceleration due to gravity (9.8 m/s), and h is the vertical height the mass is lifted. Work is measured in joules (J).
2. Power (P) is the rate at which work is performed. It is measured in W (watts), which is the same as J/s (joules per second). P = (m * g * h) / t, where t is time.
3. For a 30 degree incline, the distance traveled is double the height the mass is lifted.

and some conversion factors:

1 m/s = 2.24 mph (velocity)
1 HP = 746 W (power)
1 kg = 2.2 lb (mass)
1 N-m = .74 lb-ft (torque)

Pencils down!

1. The maximum speed of the tractor is about 8.6 mph, and it is attainable with the tractor operating at 2700 RPM.

2. If you operate the tractor at 1600 RPM, which corresponds to maximum torque, the maximum speed is about 5.8 mph.

3. Even if you boost the torque of the engine (without increasing the rated horsepower), the maximum speed will still be 8.6 mph.

Cheers

 

[tomato coupe]

View attachment 372140 View attachment 372141

Here's an interesting comparison- the Kubota graph posted and one from an older lower revving and larger displacement tractor engine
two tractor engines with equal peak rated horsepower- which one has more average horsepower and will do more real world work when run at non peak rpm... as in pulling a plow or other heavy implement from a dead stop in a geared transmission tractor :stirthepot:

I believe a higher torque / lower peak rpm engine is better suited to tractor work.

attachment problem? View attachment 372157

I'm not quite sure what situation you're proposing here. Are you talking about getting the engine up to full operating RPM quicker, or are you talking about intentionally running the engine at lower RPM?

 

[sawtooth]

A 8N will run a 5' hog. Something is wrong with the Jubilee or your hog or the grass is super thick.

Yes a 8N will run a 5' but not well in deep stuff. But it's only 27 or so PTO hp correct? Now my NAA runs a 5ft ok if I stay I stay in first in thicker stuff. BUT I have to run it WOT and it's giving everything it's got. Can't say it gets pulled down to where I stop but definitely moans a lot and I Gotta go real slow. Never burns oil and has great oil pressure. My point is I don't see anyway it can handle a 6' in the same grass period but I'm going test this theory. Just need to wait a few more weeks. The 2810 on the other hand goes through same grass and doesn't seem to struggle at all even with the bigger and much more heavy gear box which in theory should require more power to operate.

 

[LD1]

A bigger heavier gearbox and blades dont really take any more power to operate. The power required to turn just the components is peanuts in comparison to doing the work of mowing.

And sometimes the heavier blades and gearbox can help power through a thick spot, since once at speed, it has more inertia.

 

[SPYDERLK]

Pencils down!

1. The maximum speed of the tractor is about 8.6 mph, and it is attainable with the tractor operating at 2700 RPM.

2. If you operate the tractor at 1600 RPM, which corresponds to maximum torque, the maximum speed is about 5.8 mph.

3. Even if you boost the torque of the engine (without increasing the rated horsepower), the maximum speed will still be 8.6 mph.

Cheers

Yes. As said or forcefully implied many times by those who have come to understand physical science.
larry