Mixing Tire types on FWD

[voodoo]

I currently have an Iseki TE4270 (TL2500F in USA), set up with Turfs all round. The fronts are Bridgestone PD1's 212 x 80D - 15. Rears are Bridgestone PD1's 333 x 80D - 20.
I have just found a set of Bridgestone Farm Service LUG tires (AG's) and rims, size 8-16 for the front.

Two questions;
Firstly the parts manual shows a Bridgestone 7-16 AG tire. Will the 8-16 still be within spec. and not adversely affect the FWD ratio. My rough calcs estimate that if the rear was a 11.2 - 24 Ag as per manual the gearing ratio changes slightly anyway from 1.46 to 1.49. Mixing tire types front and back gives a ratio of 1.43. The same increment in the opposite direction.

Secondly, will an AG setup on the front improve traction?
I'm keen on this setup because I generally find that it is the front that breaks traction first and then drains power from the machine. On slick wet clay with 2 tonne of clay in the dump trailer, I find that the rears are often ok, but I cannot get traction or directional control when reversing a load to dump.
My theory is that with the front end being lighter, (No loader), I will be able to use on clay as the need arises, but also I will be able to travel on lawns without marking them unduly.

Any thoughts and suggestions appreciated. I'm only thinking about this because the wheel set has become available. I cannot afford the option of a complete exchange set of AG's and rims at this time. If it's not feasible to mix & match, I'll just stick with the turfs.

 

[normde2001]

If you are light enough in the front end to lose steering, (directional control), I don't think different tires will help; however 200-250# of suitcase weights on the front would probably help immensely.

 

[drm]

I agree to try the suitcase weights. I have a NH TC33 FEL with Turfs and never break the front tires loose. If the implement I have on back is too light the backs will spin quickly. I do not want to load the tires due to a new soft lawn and NH turfs can not be weighted.

 

[voodoo]

Norm,
I already have a full row of suitcase weights hanging off the front. They in themselves definately do make a difference.
I think it is primarily the ground that causes the problem.

I have an area of ground where topsoil is stripped off for regrading. I have been stockpiling loads of clay and topsoil in this area for future shaping. On grass, gravel or concrete, I have no problem and very seldom do I use FWD on these surfaces.
However, the clay, especially at this time of year gets a slick slime layer for the top 2" from groundwater run off.
No matter how I would like otherwise, sometimes I have to go onto this area in wet weather. It is then that the front slithers about. I had been hoping that the AG tires would cut down through this slime and keep directional. Strangely, the rears provide quite a good grip on this surface, I think primarily due to the drawbar load.
When it gets to the point that both front and rear axles are slipping with differential engaged, I know its too wet to be on it at all. !!

This limited use of FWD on loose surface makes me think that I could run the AG's up front safely without axle wind up.

 

[KiotiJohn]

Check out this great article on choosing the right tires. There is a section on lead lag that will help you determine what's best. There is also a lot of other great information. John
Tire Information

 

[RickB]

Here is an easy way to cut through the issue. Find the static loaded radius of the tire that was original equipment on the front of your tractor. This info is commonly found on the tire manufacturer's online tire spec catalog. You can substitute any tire of any tread style that has a static loaded radius within about 5% of the figure listed for the original tire. Rolling circumference can also be used for the same comparison. Commonly there is an Industrial tread tire that will match up with a turf. Ags are a little harder to match.

 

[voodoo]

Rick,
Thanks for the information. I had read that a front overspeed between 0-6% was designed into FWD machines. However, you need to know the overspeed of the installed tires before you look at alternatives and their ratio. Your 5% variation on rolling circumference seems a good rule of thumb.

Interesting to note your comment about industrial R4's. Are you suggesting that there would be an industrial that would give the same rolling circumference and fit the original rims? If so this might be a better idea and change all 4 tires. Fronts are getting close to needing changed anyway, so now might be the time to change them all. It is the cost of replacing rims that is prohibitive.

Any leads as to where I might get information on equivalent industrial tires?

 

[KiotiJohn]

Turf tires are often the same size as industrials in width, but AG tires are much too narrow for swapping out to industrials. Maybe you can find R4's in the size of your turfs and swap them all. John

 

[rambler]

It is the front tires that rip up sod, ags in front will be much worse for ripping than just ags in back. IMHO.

You seem to understand the matched tire issue, that the front needs to move faster than the rear by a tiny fraction or there is trouble.

It is common for the front tires to spin out first, just how things are designed as they spin faster & are smaller. Nature of the beast.

Damp clay is just trouble, my whole farm is mostly clay. Good luck with it. /forums/images/graemlins/smile.gif

--->Paul