Kubota B2650 HST in neutral down paved road hills?

[Rock Crawler]

I mow my father in laws 4 acres every 4 weeks or so with my B2650 HST, and instead of trailering it 4 miles I just drive over and do the job, and drive back to my home after. It takes as long to load and unload from the trailer as it does to just hammer down in high range and drive there.

On the way there I go down 2 long steep hills on paved roads that are around 1/4 mile each. Typically I get to the top and kick into neutral and run the throttle to idle and let it fly. I would guess that I am doing 35-40 MPH for 30-40 seconds straight before it tapers off. Is there any negative to this?

My father farmed this area back in the 60's and said that they always/regularly did the same on the old gear tractors and never thought twice of it. So I just want to make sure that there is no TECHNICAL/MECHANICAL reason that would say that this is detrimental to the rear axle/HST on the tractor. No need for the safety police to scold, I'm not interested in that angle for the intent of this question.

 

[LouNY]

The one thing I'd say is your SMV sign is for under 25 mph, you could get a sheriffs deputy in a bad mood some day.
Hang on good

 

[Fuddy1952]

I wouldn't do it for many reasons, although in a hurry lots of times while in top gear I shove in the clutch gaining speed then ease out to slow down. It neutral you have no control.

 

[3Ts]

Typically bearings and other moving parts are only designed for "at least" 20 mph. I'd be concerned about 1) exceeding the bearing speed limit and 2) the steering linkage and it's responsiveness to small corrections. Titan says their tires are designed for 30 mph. Keep in mind that double the speed does not just double the forces, it's 4 times. The physics formula includes the square of the velocity.

However, there is some discussion about Ag design criteria I've seen (Google) that talks about 20 mph, or 25 mph, and a few higher speeds. The design speed seems to be focused on the braking system with the higher speeds requiring a more robust and reliable braking system.

Having said that, I have come across a reference to "high speed tractors" that get up to 40 mph. It's your decision on what you do, you know your capabilities and those of your tractor, just remember that with higher speeds, things go to pot quicker as well.

 

[Rock Crawler]

I wouldn't do it for many reasons, although in a hurry lots of times while in top gear I shove in the clutch gaining speed then ease out to slow down. It neutral you have no control.

My tractor is a newer model and has oil bathed brakes in the rear axle housing. I do actually use the brakes to scrubb some speed and then let off and let it build again before scrubbing off speed again. If I had a tractor without a reliable and effective brake system, you are correct... and I would not kick to neutral!

 

[Rock Crawler]

Typically bearings and other moving parts are only designed for "at least" 20 mph. I'd be concerned about 1) exceeding the bearing speed limit and 2) the steering linkage and it's responsiveness to small corrections. Titan says their tires are designed for 30 mph. Keep in mind that double the speed does not just double the forces, it's 4 times. The physics formula includes the square of the velocity.

However, there is some discussion about Ag design criteria I've seen (Google) that talks about 20 mph, or 25 mph, and a few higher speeds. The design speed seems to be focused on the braking system with the higher speeds requiring a more robust and reliable braking system.

Having said that, I have come across a reference to "high speed tractors" that get up to 40 mph. It's your decision on what you do, you know your capabilities and those of your tractor, just remember that with higher speeds, things go to pot quicker as well.

That is what I am looking for. Mechanical design limitations. So in the 20-25 MPH area would be a theoretical upper limit. I can deal with that, I will modulate brake applications accordingly and not let it "zing" down the road at traffic speeds

Thank you!

 

[Industrial Toys]

The faster you go, the more dangerous any given situation could become. Not likely, but say a wheel locked up?

Here is another thing to consider. I'm guessing you don't have the MFWD disengaged while traveling on the road. So you ONLY have back brakes, that may not be perfectly matched and could pull dramatically in a panic stop.

I remember as a twelve year old kid driving our new tractor on the back roads. That thing just couldn't go fast enough to please me. Even unwired the high limit screw on the injector pump and took it out a few turns.

 

[Fuddy1952]

Here are a few calculations...
4 miles averaging 15mph= 16 minutes.
4 miles averaging 20mph= 12 minutes.
4 miles averaging 30mph= 8 minutes.
Average recovery time, broken leg, (minor)=
70,560 minutes.

Sooooo I would allow 8 extra minutes= 2 minutes a week, enjoy the ride and a soda!

 

[dodge man]

I've done it on my BX a couple of times, but it has terrible road speed, like 7mph. I also probably don't go over 15 mph. If the pavement was really smooth, its probably not dangerous but if its rough at all, not safe.

 

[Rock Crawler]

I've done it on my BX a couple of times, but it has terrible road speed, like 7mph. I also probably don't go over 15 mph. If the pavement was really smooth, its probably not dangerous but if its rough at all, not safe.

Yes, it's smooth and it doesn't even gone at bouncing or anything at all that indicates that you couldn't go faster. When I first did it I was a bit spooked and was ready for a near death experience. Now I roll down the mountain side with one hand on the steering wheel and the other holding a cold Corona up to my mouth

Kidding on the beer part. But it honestly rides and handles about as good as my Wrangler JK.