Driving a HST

[ovrszd]

Does that constant high rpm get to you after a while. That's the part I don't think I'll appreciate.

For me,,,, yes.....

The only time I use the hand throttle on my M9540 Shuttle is to do PTO tasks. The rest of the time it's at an idle. You can't do that with HST. Don't even try it, you'll be greatly disappointed. And it doesn't matter what HP tractor you are running. It's just like a stick shift pickup versus an auto pickup. It is essential that you turn rpms with HST to get any production. Without rpms it will stall.

I'm hoping you can adjust and enjoy the HST. Just be patient and give it time. As I said earlier, you're first thoughts are going to be that it's underpowered. Rev it up and most of that goes away, not all, but most.

Edit: meant to add, on my HST JD mowing tractor, I never run it at idle. Always have 1/3 throttle or more.

 

[k0ua]

Does that constant high rpm get to you after a while. That's the part I don't think I'll appreciate.

I vary the RPM quite a bit, I will back off of the RPM a bit. when it is not really needed. The new Kioti's do have a throttle linked pedal. The Kubota Grand L's have had it for a long time. I would imaging other deluxe tractors across brands also have it.

 

[phiferpharm]

The only thing many DK owners find is that the hand throttle can be very tight when you get it. I might add that it doesn't seem to loosen up much with time and use, so be prepared to loosen it up if it is too tight. I haven't loosened it up or lubed it, but I should. There are several threads about the best way to do this (unless I'm mistaken I think James has posted about this).

 

[s219]

I would caution against loosening hand throttles -- they are meant to be tight by design (usually have stacks of disc springs between plates) to have enough friction. Otherwise, the vibrations of the diesel would cause the throttle to move on its own. In fact there are occasionally threads here from guys who need to tighten the throttle to keep it from drifting. So I'd try carefully lubing it first, but avoid messing with the springs or plates.

Re: the main topic, I find that the operating procedure for HSTs is very consistent with how diesels are used, especially if you think of the HST pump as a separate piece of working machinery (it is, it's a pump basically). I grew up using all sorts of diesel equipment and the first thing you'd do is throttle it up to an operating RPM before engaging whatever machinery there was. Machinery attached to trucks or other drivable construction equipment even had separate hand throttles (often on the opposite end of the machine from the driving station) just for that purpose. Diesels are very efficient when you put the RPM in the meat of its range and leave it there while doing work.

Chuck, you seem like you're between a rock and a hard place with the CK to DK trade, but maybe you should test drive an HST DK before committing. Or look at some other models/brands available with the HST+ types of transmissions that link throttle to the HST pedal(s). To me that may be the best of both worlds.

 

[chuck172]

I vary the RPM quite a bit, I will back off of the RPM a bit. when it is not really needed. The new Kioti's do have a throttle linked pedal. The Kubota Grand L's have had it for a long time. I would imaging other deluxe tractors across brands also have it.

What's a throttle linked pedal? This is starting to get complicated.

 

[k0ua]

Many DK owners (including this one) have had to lube up or loosen up that hand throttle.. It is too tight. Here is how.

http://www.tractorbynet.com/forums/...ottle-lubrication-pix.html?highlight=throttle

By the way if you missed it, here is how slow you can go with a Hydro transmission. Inch worms can overtake you!

http://www.tractorbynet.com/forums/...4-how-slow-can-you-go.html?highlight=throttle

 

[k0ua]

What's a throttle linked pedal? This is starting to get complicated.

Instead of what I told you in a previous post about setting the hand throttle at 1800 or 2000 or above depending on the job, you can "link" the throttle to the pedal that controls the swash plate in the hydro. So you can leave the hand throttle at some lower setting and then when you step on the go pedal, it will also up the throttle. So as you start to need torque from the engine it will automatically throttle up as you start to load it, and it will also throttle down as you let off of the pedal. Kubota Hydrostat plus has had this feature (and many more) for some time. Kioti now has it as well in the new NX series. The DK series does not have this feature.

 

[the old grind]

IMO what James and nybirdman said on page 2 could (should?) be laminated into a quick start guide for those new to HSTs. :thumbsup:

C172, expect more back-pats for choosing such a nice machine. I wouldn't sweat the expected noise (and thirst) of high rpm running. PTO implements may soon drown that out with their own racket. Field and brush mowers want full (540) PTO rpms, but tillers, PHDs, and many others can be scary at such speeds. (I'd bet you're rpm will be in the high teens 90% of the time too.) Congrats!

 

[oldpilgrim]

put the throttle wherever it 'feels' right for you. I very seldom put mine over 15-1800. I had pushed it up to 2000 when driving down the road. You'll find you will very infrequently use the throttle.

Don't over think the hst stuff. It simple, versatile, works, works easily, and works very well.

 

[TJP89]

I find that once I get the engine up over 2000 it smooths out and isn't too loud. Running at PTO speed (2400-2500 I think) with the cutter gets LOUD however, but that's true on any tractor.

The only time I run in idle is when I'm just moving around behind the barn from implement to implement over very short distances. Everything works at idle, just very slowly, and a lot of doing that can't be good for the tractor.

I found the HST very intuitive to use, much more so than a gear tractor. If you play around with it a little, you'll get the hang of it quick.