Operating Tips

[ponytug]

How did you work out the pressures to determine least motor wear?

... Try reversing the wheels for greater safety and stability!
In a PT425, use 11# of air in the front tires and 7# in the rear for the best traction, nicest ride, and least wheel motor wear!

 

[FOURTEEN]

How did you work out the pressures to determine least motor wear?

I want low impact on the motor bearings, enough carrying capacity, and a nice ride, so, on a concrete floor:

For the FRONT tires, I loaded the bucket to achieve pucker, then adjusted the tire pressure to about one half of the unloaded height. 11# has worked well. Enough air to prevent tire, or wheel, damage, but soft enough for a full footprint, to absorb shocks, and to provide a gentle ride when loaded or unloaded. When loaded the tires will 'caterpillar' up over obstuctions like rocks or logs. (A 'D' shaped tire rather than an 'O'.)

For the REAR tires, with the bucket empty, I adjusted the tires to be soft but with a flat, even footprint all the way across the tire without any cuping or bowing. 7# has worked well.

 

[BobRip]

Use your Power Trac to lift and hold large boards in place while nailing. I just used this on a 2 X 10 X 10ft board. No way could I hold this while nailing.

 

[Red Zebra]

Just today....

Put a pallet on the pallet forks....leveled with the truck and off loaded new washer and dyer. PUt them in storage in my barn until the house is ready.
Placed the washer in the corner...then leveled the dryer pallet with the top of the washer and stacked them. (They're designed to do this). Great back saver!

Will use the PT to move all appliances fromt the barn to the house when complete. About 400 ft away.

Hint: Strap the the load to the pallet to prevent it from toppling off when moving, lifting, etc.

 

[J_J]

How did you work out the pressures to determine least motor wear?

The size of the load will have the most effect on the wheel bearings, whether it is a rolling load or a bouncing load The side load will be the same no matter what the tire pressure, except when the load is bouncing. Lower air pressure will give a softer ride, but may also contribute to tire roll off. The advertised tire pressure for a certain tire is the pressure for the maximum load. You will notice that as the plies are increased, the max load increases. The price also goes up. The tire pressures that Fourteen published is for a PT-425

 

[ponytug]

Great points JJ.

I had enquired about the process so that it might be applied by others to determine tire pressures optimal for their purposes.

Unlike some folks, I do pretty much everything at slow speed, and usually on a slope. I'm happy with my current tire pressures, but I am always curious to learn more.

All the best,

Peter

The size of the load will have the most effect on the wheel bearings, whether it is a rolling load or a bouncing load The side load will be the same no matter what the tire pressure, except when the load is bouncing. Lower air pressure will give a softer ride, but may also contribute to tire roll off. The advertised tire pressure for a certain tire is the pressure for the maximum load. You will notice that as the plies are increased, the max load increases. The price also goes up. The tire pressures that Fourteen published is for a PT-425

 

[FOURTEEN]

""Lower air pressure will give a softer ride, but may also contribute to tire roll off.""

That is why I said: " 11# has worked well. Enough air to prevent tire, or wheel, damage, but soft enough for a full footprint, to absorb shocks, and to provide a gentle ride when loaded or unloaded. ". Less than 11# can cause tire damage including that described by JJ. 11# seems to be the best compromise to prevent damage from both overly soft and overly hard tires on the Front of the PT-425.


'''The advertised tire pressure for a certain tire is the pressure for the maximum load.'''

True, but you seldom use maximum tire pressures. The advertised tire pressure is the maximum load allowed on the tire, not the maximum load allowed on the vehicle. With the OEM tires on my wife's Azera, Azera calls for 30#, far below the maximum tire pressure of 51# listed for that tire. At 51# each tire could carry a load of 1653#, but that would be excessive for a 3600# car, and would cause the car to ride and handle terribly, while possibly leading to suspension damage. On that car 30# provides the best ride and handling while protecting both the tire and the suspension. When I first bought my PT, I asked PT what the best tire pressures would be, but they didn't have a clue! So, as usual with my PT, it was 'do it yourself' time!


""The tire pressures that Fourteen published is for a PT-425.""

True, but the same proceedure could be used to find the best pressures for any model PT.

PS: Note the tire profiles in this full load picture. (Also my handy 'saw holder'!!)

.

 

[cqaigy2]

Seems like the lower pressure would help reduce the peak shock on the wheel moter.

 

[FOURTEEN]

Seems like the lower pressure would help reduce the peak shock on the wheel moter.

Exactly!!!

 

[J_J]

[ True, but you seldom use maximum tire pressures. ]


I disagree with that statement. I would venture to say, that about 95 % or all tires are run at the rated pressure. It only makes sense in the fact that tires are selected for load caring ability.

Yes. I agree that some vehicles use less air pressure in order to give a stable ride.especially when there is a large offset between the weight distribution on certain vehicles. If tires on these vehicles use max tire pressure, there will be less of a footprint, with the tendency to drift. The same is true about pickup trucks. If you use maximum pressure, you will have a stiff ride, and you will wear out the center of those . Some people reduce the tire pressure for a softer ride and a better footprint.

A bouncing tire will have a greater load on the bearings than the static load

Try this. Lay a 5 lb brick on your hand, no problem. Now, pick that brick up and drop it on your hand from 1 ft. Dynamic forces are involved here, and it will hurt like ****.