Tire Grooving Advice

I am just about to buy a Ideal Heated Knife for grooving some tires. I have a set of Hi Tec Retreads (33x12.5x15 MT) that I plan on practicing on (currently useing them and will be replacing soon).


And will be replacing them with some TSL bias-ply's (33x12.5x15). This truck is only driven on the street to and from the trail and will be trailered in the not too distant future.


I have 3 questions:
1. how does grooving increase tire life?
2. is there any reason I should not sipe them and groove them?
3. does anyone have preferences for design of grooving either tire? (Originally I was going to just cut the V's in half, but have seen other ideas and want opinions on other thoughts)

Thanks,
Michael

don't know about change in wear, here is how I grooved mine....

So, why did you decide to cut the chevrons in three pieces in stead of two?

I assume you left the outside lugs only partly cut to protect from ripping?

Any idea of what size blades you used for each cut?

Would you do the same thing next time.

Here is my original idea (any comments?)


And here is another idea I saw (any comments?)


Thanks,
Michael

grooving is mostly to allow the tread bolcks to conform and move around better siping on the other hand is what increases tread life and improves traction.

bj-666 said:

grooving is mostly to allow the tread bolcks to conform and move around better siping on the other hand is what increases tread life and improves traction.

Click to expand...

I have heard/read that both siping and grooving can increase tread life. I wonder if anyone has a better explanation than heat disapation?

Thanks,
michael

No other opinions?
Is not that common?

Thanks,
Michael

not too sure why siping or grooving would increase tread life.

Tire wear can be acclerated by excess heat - sure. But to generate that excess heat you would need to be running the tire VERY underinflated (trail psi), and be driving at highway speeds (remember the Ford Exploder/Bridgestone fiasco).

By grooving the tire you could actually increase tire wear. More grooves = less tire surface area = more wear at the same load. But if you only drive to and from the trail or intend trailering the XJ soon then this should not be a problem, or even noticeable.

When running "street" tires (tires with a wear rating exceeding 200) on a race car we have the tires shaved, typically to 3/16 tread depth. The full tread tire can squirm (move about laterally) under racing loads, and this is what generates the excess heat. That heat leads to blistering and can destroy a tire within a few laps.

Perhaps that is where the grooving/siping leading to extra tire life rumor originated.

From personal experience with siping tires - again for a race car, competing in rally and ice racing - this actually accelerates tread wear. By siping the tire (we cut the tire every 1/4") the tire is way more susceptible to "chunking" or ripping off entire tread blocks. But the increased grip on icy surfaces is very, very noticeable. Most rallies in the USA do not allow spikes of any sort, some FIA santioned events excepted.

My 38" TSL's may only have a few hundred miles of trail use on them, and they are chunked, the edges of the tread blocks are ripped and torn, and there are areas of the sidewall that are suspect. The tires will be shot long before the tread is worn.

HTH,

I am interested if anyone can provide some logic to the siping/grooving increasing tread life.

2xtreme said:

I have heard/read that both siping and grooving can increase tread life. I wonder if anyone has a better explanation than heat disapation?

Thanks,
michael

Click to expand...

Try here...
http://www.discounttire.com/dtcs/tireSiping.dos
or
http://www.sipers.com/sipers/index_large.asp -> under increased tread life

It is what I had done to my MTR's On Bigger lug tires they only sipe down about 50% depth and 50% of the center of the tread to prevent the lugs from "chuncking out"

Did I get 200% improvement over unsiped tires? I do not know. This is the first set of MTRs that I have owned.

2xtreme said:

I have heard/read that both siping and grooving can increase tread life. I wonder if anyone has a better explanation than heat disapation?

Thanks,
michael

Click to expand...

Heat disapation is very important when it comes to tire wear, especially if driven on pavement. Large lugged off-road tires don't disapate heat well, therefor letting the tread wear quick. The hotter a tire gets the easier it wears. Siping and grooving both decrease the amount of tire contacting the road and allow the tread lugs to flex more. The grooves also provide more surface area, which help disapate heat.

OK, I will go along with all the concepts that siping and grooving could extend my tread life stricktly by heat disapation. Not that this is likely for me since I go through sidewalls and destroy the tire well before the treads are gone also (almost no street use, just on the trail). My current tires are siped and there is a huge different in performance with them on the rock and snow/ice. I will sipe my next tires also.

But what about the pattern I use for grooving. What determines what pattern I should use to groove my new tires?

I have seen a variaty of paterns and would like to better understand what pattern works best in what conditions?

Thoughts?

Thanks,
Michael

I think the tire you choose dictates the grooving,your trying to make smaller lugs out of bigger ones.To small and youll tear them off,I would always groove 90* to the lug.

Here is what I ended up doing to my first set of tires.


I used a Number 4 blade for the inside lugs and a Number 2 blade for the outer lugs.
Took about 3 hours to do all 5 tires (taking them off the jeep and rotating them at the same time). I did do the fronts on the jeep but prefered taking them off in the long run.

I will be doing a set of swampers next.

Michael