HST vs shuttle

[MossRoad]

Additionally, unless you can run your brakes with one foot and HST with other, Shuttles are much more precise.

My late 70's IH2500b had the directional pedals on the left foot and the brakes on the right foot. Worked great!

My Power Trac has a treadle, with the right foot forward and left foot reverse. No brakes. None. No need.

 

[goeduck]

Patrick,
Disagree. HST sacrifices more than a tiny bit of HP. In small tractors 5 hp is significant. You would NOT be faster at a repetitive function than me, W/ the newer hydraulic shuttles. The 5125r I use has F-R buttons on the loader joystick. The power reverser lever isn't even necessary, but is available. I can push a button, already under my hand, faster than you can shuffle your feet on floor pedals. Also, HST generates significant heat under load, efficiency loss, and friction wear!.


HST is Old School,, time to catch up.

I have an older shuttle and really like the feel of the gears, I also have an older HST and really like the accuracy. But it sounds like shuttles have come a LONG way from reading your post. A LONG way. I knew HSTs did but did not know shuttles did.

 

[ArlyA]

HST does indeed require or use, quite a bit of HP. Depending where in its range its being operated, they run in losses of 10 to over 20%. These high losses is why we can't use Hydro UTV's in our snow industry. Just the same, for loader and other dirt work, we are looking to purchase HST tractor. Let me add, a geared transmission uses less than 5%.

Patrick,
Disagree. HST sacrifices more than a tiny bit of HP. In small tractors 5 hp is significant. You would NOT be faster at a repetitive function than me, W/ the newer hydraulic shuttles. The 5125r I use has F-R buttons on the loader joystick. The power reverser lever isn't even necessary, but is available. I can push a button, already under my hand, faster than you can shuffle your feet on floor pedals. Also, HST generates significant heat under load, efficiency loss, and friction wear!.

HST is Old School,, time to catch up.

 

[MossRoad]

Fuel savings for the HST VS Gear argument for the average compact utility tractor owner is a non-issue, so don't let anyone scare you off with talk of excessive fuel usage. Here's why...

If you're a typical compact tractor owner, you're only going to put 50 hours of usage on your machine in a year. If the geared machine uses 1 gallon per hour, that's 50 gallons of fuel a year. @ $3.00/gallon, that's $150 per year in fuel cost. If the HST uses 20% more fuel, that's an additional 10 gallons and $30 more for the entire year.

Also, I read this talk of HP losses on HST quite often on TBN and usually reply with this.... HP is HP, no matter what produces it, and if you have a tractor rated at 35HP at the PTO, it puts out 35HP at the PTO, and if it's rated for 35HP at the drawbar, it pulls 35HP at the drawbar.

So, get a tractor that specs out with enough PTO or drawbar HP to complete your tasks. Same thing applies to either gear or HST. Get the machine that you are most comfortable on, that is rated to do the work you need to do, and don't worry about HP losses through the transmission or fuel economy.

 

[rScotty]

Patrick,
Disagree. HST sacrifices more than a tiny bit of HP. In small tractors 5 hp is significant. You would NOT be faster at a repetitive function than me, W/ the newer hydraulic shuttles. The 5125r I use has F-R buttons on the loader joystick. The power reverser lever isn't even necessary, but is available. I can push a button, already under my hand, faster than you can shuffle your feet on floor pedals. Also, HST generates significant heat under load, efficiency loss, and friction wear!.
HST is Old School,, time to catch up.

I would expect that HST would use more power than direct drive gears. And for those who normally run their tractors at full RPM under load it could be noticible - or maybe not. I'd like to read some studies on HST efficiency before passing judgement on power sacrifice. Or on longevity for that matter.

However, one efficiency advantage of HST that doesn't get mentioned enough is that the HST transmission is always in exactly the right gear to develop peak engine torque. The gear ratio can't help but be right because that is the way HST works. It's like a gearbox with an infinite number of gear ratios. And I suspect that the multirange HST trannys are even more efficient.

Even if the research shows that HST is less efficent everywhere - which I doubt - it sure is convenient and friendly to work with. Particularly on hills.
rScotty

 

[ovrszd]

Why can't you use your right foot to operate the HST and left for the brakes?

Sadly, many are designed with all pedals on right side. Have to be agile....

 

[rScotty]

Sadly, many are designed with all pedals on right side. Have to be agile....

Yep, gotta agee. My Kubota HST+ is designed that way. Both brakes and the HST are on the right. Only the clutch is on the left in my Kubota HST
.
I think the layout got to be that way because in a car it is typical to work the brakes and accelerator with the right foot and use the clutch with the left. So the designers - who maybe have never driven a tractor - just copied the automobile layout without thinking about why it was that way.

Because what the tractor manufacturers overlooked is that in a car a person won't be using throttle and brakes simultaneously - where in a tractor they will sometimes. Or at least we used to. Back in the days when most tractors were 2wd, using the wheel brakes was about the only way to get the front of the machine to turn instead of just pushing dirt. Luckily using brakes and throttle together is not required as much as it used to be now that we have 4WD with sharp turning radius. But the ability is still needed and used.
As ovrszd says, it requires agility.

I think every person who has ever weighed in on foot pedal position agrees that the layout would be a lot better if the brakes were on the left next to the clutch. And moving the brakes would give space on the right to move the HST to a better - more central - position as well.
I wonder how long it will take manufacturers to notice.

Has anyone done those pedal modifications to their Kubota? 4Shorts?
rScotty

 

[ericm979]

Many HST tractors now do not have a clutch. That leaves room to put the brake pedals on the left.

 

[MossRoad]

There should be two directional pedals on the left, and split brakes and a throttle pedal on the right, as well as the differential lock operated by my right heel, like my IH2500b had. I loved that layout.

 

[DK35vince]

Fuel savings for the HST VS Gear argument for the average compact utility tractor owner is a non-issue, so don't let anyone scare you off with talk of excessive fuel usage. Here's why...

If you're a typical compact tractor owner, you're only going to put 50 hours of usage on your machine in a year. If the geared machine uses 1 gallon per hour, that's 50 gallons of fuel a year. @ $3.00/gallon, that's $150 per year in fuel cost. If the HST uses 20% more fuel, that's an additional 10 gallons and $30 more for the entire year.

Also, I read this talk of HP losses on HST quite often on TBN and usually reply with this.... HP is HP, no matter what produces it, and if you have a tractor rated at 35HP at the PTO, it puts out 35HP at the PTO, and if it's rated for 35HP at the drawbar, it pulls 35HP at the drawbar.

So, get a tractor that specs out with enough PTO or drawbar HP to complete your tasks. Same thing applies to either gear or HST. Get the machine that you are most comfortable on, that is rated to do the work you need to do, and don't worry about HP losses through the transmission or fuel economy.

Very few if any compact tractors list draw bar HP that I remember seeing. So hard to say if there is a difference in draw bar HP.
Generally see some PTO HP different between HST and gear listed in the specs in the same make/model.