L2501HST Fades in High Range on the Road
- Thread starter harripm
- Start date
Turbo or any other power enhancing technique. 
You simply don't have enough HP. Back off the foot pedal.
Of course I'm assuming fuel and air delivery are within spec along with the overall condition of the drivetrain.
You simply don't have enough HP. Back off the foot pedal.
Of course I'm assuming fuel and air delivery are within spec along with the overall condition of the drivetrain.
Magicman
Well-known member
Lifetime Member
Equipment
M4900 Utility Special 4WD e/w FEL & 1530 John Deere "Traveling Man"
For torque you gotta keep the RPM's up. If the hill is too steep or the load too great, down shift.
I quickly found out that my Kubota does not have the low end torque/lugging power that my old John Deere has.
I quickly found out that my Kubota does not have the low end torque/lugging power that my old John Deere has.
i7win7
Well-known member
Equipment
BX2370, B2650 grapple, tree puller, trailer mover, 3 point hoist, mower, tiller
If you have loaded tires you are losing power trying to get the centrifugal forces (vs gravity) up to speed. Loaded tires increase stopping distance also.
Are you saying the 2501 is losing speed/power just driving down a graded road? If that is what you are saying then that isnt normal. I live on a dirt road and drive my 2501 around in high gear often. Going from place to place High gear works fine. It is true that the tractor has no actual torque in high range, but just driving the tractor around from point A to point B Ive never had any trouble. It scoots along pretty speedy.
dirtydeed
Well-known member
Lifetime Member
Equipment
B2650 BH77, U27-4R2, BX23TLBM, box blade, rear blade, flail mower, Stump Grinder
I believe the OP meant when driving on a road with a slight incline (going up a hill) he loses power.
I think that its a fairly common complaint for those with L2501's. I've heard it before. For all of those who wanted that extra "bulk" weight of the L to do work, you will pay for that when running in high gear.
harripm- with a hydrostat, you just need to back off on the treadle pedal to keep the rpms up. Many folks new to hydrostats typically mash the pedal (like the accelerator pedal in their car) when they want more power...the exact opposite of what they need to do when running a hydrostat.
I wasn't implying that you are new to hydrostats, just stating that its a fairly common observation.
Last edited:
Thanks for all the replies. I do have loaded tires. I also know that backing off the pedal is often required when loading the tractor, i.e. turning plow, etc. I just thought in road gear unloaded it should pull itself @ full speed. Otherwise, very happy with the tractor BTW.
Ahh, well I cant speak to that too much then. Where I am here its all pretty flat. I do have loaded tires on my 2501 as well though. I've never had any trouble driving around in high range. I have noted however that the tractor has no actual torque in high range - if you try to pull off for example with the box blade down on the ground or something you wont go too far and its immediately noticeable.
You're asking more than that 25HP engine / hydro can do. There's a hill on the way to town that slows me down with the L4240. It was much worse with the L3200. These tractors have a HI range that works best on flat or gently sloped areas. When it was time to replace the L3200 it seemed like there should be about 5 more horses for the mower and hills, plus another 5 for the A/C. Getting 10 more horsepower than the last tractor and the HST+ made quite a difference.
The loaded tires really don't add more challenge to getting the tractor rolling or stopped than having a bunch of fat people in the cab would. It's just added weight. The liquid isn't fastened to the tire unless it's frozen. The tire just slips around the outside of the liquid. Hold a bucket of water by the handle and twist it. Then stop. A filled bucket is obviously heavier, but the difference in force between spinning an empty bucket vs. a liquid-filled bucket is negligible for both starting and stopping. You're applying force to rotate the bucket and not the 40 pounds of water. If you freeze the water in the bucket so it becomes a mass that grabs the bucket, you may strain your wrist doing the same thing.
After travelling for a distance, the liquid in liquid-filled tires will eventually be rotating at pretty much the same speed as the tires. That rotation is where the centrifugal force comes from. Going fast enough and far enough it will press against the inside of the tire with an incredible amount of pressure. If the tractor stops, the liquid will continue moving inside the tire like stirred coffee in a cup. The coffee swirls around and doesn't make the cup rotate. Because the liquid isn't connected to the tire, it will just slosh inside and not attempt to keep the tire rotating. The liquid will have a forward inertia - just as the fat people in the cab.
The loaded tires really don't add more challenge to getting the tractor rolling or stopped than having a bunch of fat people in the cab would. It's just added weight. The liquid isn't fastened to the tire unless it's frozen. The tire just slips around the outside of the liquid. Hold a bucket of water by the handle and twist it. Then stop. A filled bucket is obviously heavier, but the difference in force between spinning an empty bucket vs. a liquid-filled bucket is negligible for both starting and stopping. You're applying force to rotate the bucket and not the 40 pounds of water. If you freeze the water in the bucket so it becomes a mass that grabs the bucket, you may strain your wrist doing the same thing.
After travelling for a distance, the liquid in liquid-filled tires will eventually be rotating at pretty much the same speed as the tires. That rotation is where the centrifugal force comes from. Going fast enough and far enough it will press against the inside of the tire with an incredible amount of pressure. If the tractor stops, the liquid will continue moving inside the tire like stirred coffee in a cup. The coffee swirls around and doesn't make the cup rotate. Because the liquid isn't connected to the tire, it will just slosh inside and not attempt to keep the tire rotating. The liquid will have a forward inertia - just as the fat people in the cab.
dirtydeed
Well-known member
Lifetime Member
Equipment
B2650 BH77, U27-4R2, BX23TLBM, box blade, rear blade, flail mower, Stump Grinder
Chim- you're still pulling that additional weight up a hill. You could fill the tires with concrete and it wouldn't matter. Additional weight is just that...it takes more energy to start, move, or stop it. It's physics....just sayin'
Chim, you are mistaken about the liquid ballast in the tires. The mass is the problem....not the friction between tire and liquid. To get that mass in-motion, to keep it there when changing slope (uphill) or to stop it... will require plenty of energy management. The little 25 hp tractor has to work hard to accomplish that.
Hmmm. Looks like I didn't communicate as clearly as I had wished. What I posted was in agreement with what you are saying:
" The loaded tires really don't add more challenge to getting the tractor rolling or stopped than having a bunch of fat people in the cab would. It's just added weight. "
Moving weight is moving weight, whether it's the fat guys in the cab, a big batwing mower on the 3PH or a loader bucket full of concrete. The point I was trying to make is that the centrifugal force mentioned in an earlier post is a non-player.
That said, I do expect that there are some differences between liquid and solid tire fill with regard to starting or stopping. With liquid, a spinning tire is more or less a separate entity. If you're going down the road long enough to have the liquid spin nearly synchronous with the tire, and stop the tire rotation, the liquid will continue to spin inside the tire - but not drive it.
Do the same with a solidly filled tire and when you try to stop the tire, the fill will want to keep rotating the tire because the fill can['t continue to move without transferring that inertia to the tire. Just like trying to stop a bush hog quickly.
Are you running at full 2,100 rpm? There is noticeable difference between 1,800-1,900 rpm vs 2,100 on these tractors. I regularly travel on a gravel road that has a slight grade and mine w/o filled tires, but typically with the loader and ballast box pulls it in full high. I can tell though if it was much steeper I'd probably have to back off the pedal.
Cathy is absolutely correct. Even my little B2920, which is significantly smaller and lighter than the L2501, and having more horsepower at 29, could not maintain full speed uphill in High range.