Let's Talk Big Tires for Rock Crawling

[tatum]

I'll disagree with you there Hans, gearing is a function of diameter, not weight. Horsepower will be affected by weight (rotationg mass calculations) whereas changing gearing will be the most effective way to address tire diameter.
There is no doubt, larger diameter tires have many benefits in the desert and in rock crawling. Save the smaller diameter tires for short course work.
As for the weight of the tires, yeah, it would be great for the tires to weigh less, then it would take less horsepower to spin them, but lighter usually is directly related to durability and strength.
You and I have had this discussion before, I respect your opinons and acheivements in SCORE, but for my use, feel 8 ply tires add a benefit of durability, flat protection and so on.

It was interesting to see the different tires in use at Moab last week, it did seem that both the UTV specific versus the LT tires showed different benefits.

Arctic Cat has 4.0 gearing in their 550 and 650 Prowlers, it appears those could be changed out into the XTZ (which has 3.1 gearing) to pick back up some of the loss of effective gearing...
Maybe it's time for some aftermarket companies to look into different gearing sets for other brands...

I know what a taller tire does to gearing.I also know what a heavier tire does to rotating mass and how it affects the drive line.
I believe a flexible tire will get more contact patch and give better traction.
I am talking rock crawling not desert racing.
As far as I know you can only gear a Teryx taller and not lower with out having custom gears made.

 

[Darryl89]

I know what a taller tire does to gearing.I also know what a heavier tire does to rotating mass and how it affects the drive line.
I believe a flexible tire will get more contact patch and give better traction.
I am talking rock crawling not desert racing.
As far as I know you can only gear a Teryx taller and not lower.

Very true on the contact patch from a more flexible tire, but the BFGs running on UTVs at Moab seemed to be doing really good.

 

[Crowdog]

As far as I know you can only gear a Teryx taller and not lower with out having custom gears made.

I talked with Seth over at Stateline Customs. They have a setup that reduces the gear ratio by 21%. Unfortunately, it affects both high & low. I would love for it to only affect low range.

And in general, I wish most all sport UTVs came with a lower low range. There is no need to be able to drive 25mph in low. Low should be 15 mph max right out of the box.

 

[Darryl89]

I talked with Seth over at Stateline Customs. They have a setup that reduces the gear ratio by 21%. Unfortunately, it affects both high & low. I would love for it to only affect low range.

And in general, I wish most all sport UTVs came with a lower low range. There is no need to be able to drive 25mph in low. Low should be 15 mph max right out of the box.

Yeah, they don't need speed in low.
I run 18 and 19 gram rollers in my primary to keep the revs higher, effectively doing the same thing, but I do lose top speed, but then again, I gain the top speed back with the larger tires.

 

[tatum]

He is probably changing the final drive gears like when you put in brute force gears.That is actually a pretty easy swap and you dont have to split the cases.
If someone made a lower low range gear that would be the way to go.

 

[TREE68]

i would like to bring up an old subject. because after KOH i plan to get tires/wheels. on my teryx. im going same size all around (includind the spare) thinking 7 inch width on wheel. beadlocks. 15 inch if i can. with falkens or KM2 BFG. had KM2 on my jeep, and falkens on my z71. so i like both. i ride johnson valley desert 100% of the time. so desert/rocks.