Skinny Tyres Vs Fat Tyres

Sorry to bust your bubble uninformed, but Q78's aint all that skinny. The designation on paper is 35.5 x 9.5 but let me tell you they are around 11.5 inches wide. I fitted a Q78 and a 34x 9.5 on 15x7 for a fit test on my 130 2 weeks ago and the Q78's are HUGE.
I am a massive fan of skinny. I run 7.5 x 16 xzl's everywhere and love them. But as I keep stating repeatedly, my rig is a tourer(not that you would know by where I take it) and I am more than happy with the ALL ROUND performance these give. I would look more at the 34 TSL's than the Q78's for play tyres as I don't feel like cutting up my guards.

CC

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Originally Posted by Col.Coleman

Sorry to bust your bubble uninformed, but Q78's aint all that skinny. The designation on paper is 35.5 x 9.5 but let me tell you they are around 11.5 inches wide. I fitted a Q78 and a 34x 9.5 on 15x7 for a fit test on my 130 2 weeks ago and the Q78's are HUGE.
I am a massive fan of skinny. I run 7.5 x 16 xzl's everywhere and love them. But as I keep stating repeatedly, my rig is a tourer(not that you would know by where I take it) and I am more than happy with the ALL ROUND performance these give. I would look more at the 34 TSL's than the Q78's for play tyres as I don't feel like cutting up my guards.

CC

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first of all was that the widest point or the tread width? because EVERY tyre is wider than there specified width. ckeck out the simex they are alot wider than there specified width...my 235's are 250 (spare and mounted)

secondly you were running 15inch rims which will be slightly different than a 16.

thirdly you mounted them on a 7 inch rim, they recomend a 6.5, and they will even mount to a 6 inch rim, just run a bead lock to make sure, on a 6 inch rim they will be tall and skinner than a 7.....


my point anyway is find a narrower tyre this tall ???

Serg

Regardlees of all that, they are a massive tyre. Not what I had envisaged from the size description having seen them in the flesh. The next size down, the 34 x 9.5 is a giagantic difference. more in keeping with what I had in mind, a taller skinny trye.
My 7.50's I have 14 tyres all up all xzl's. 7 on 7 inch rims, 5 on 6.5 inch rims and 2 on 5.5 inch rims. It doesn't make that much difference really.

A 9.5 x 16 Michelin XZL is around 36.6 inches tall and only 9.5 wide, but the difference is a tsl is $345 and the Michie is around $700.

It is all alot different in real life rather than on paper. (i knew I should have taken a photo). Just don't want you quoting it as a skinny tyre as it is no-where near what I call skinny.

CC

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Originally Posted by Col.Coleman

Regardlees of all that, they are a massive tyre. Not what I had envisaged from the size description having seen them in the flesh. The next size down, the 34 x 9.5 is a giagantic difference. more in keeping with what I had in mind, a taller skinny trye.
My 7.50's I have 14 tyres all up all xzl's. 7 on 7 inch rims, 5 on 6.5 inch rims and 2 on 5.5 inch rims. It doesn't make that much difference really.

A 9.5 x 16 Michelin XZL is around 36.6 inches tall and only 9.5 wide, but the difference is a tsl is $345 and the Michie is around $700.

It is all alot different in real life rather than on paper. (i knew I should have taken a photo). Just don't want you quoting it as a skinny tyre as it is no-where near what I call skinny.

CC

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we are using the term skinny in regards to common 4x4 usage, you cant compare a 750/16 radial to a 36 inch tall crossply dedicated offroad tyre. so yes, a 750/16 is a skiiny tyre when compared to most daily driver 4x4 tyres and yes, a q78 is skinny compared to most hardcore offroad tyre.

mounting a 750/16 on 5.5-7 inch rims won't have as much variation as a q78 with alot more sidewall height. think of it in percentage increase, so the bigger tyre will vary more. but same percentage.

if your looking for a good 4x4 in 750/16 look at the simex m/p treker.

regarding the 900/16 xzl, i looked at these. Apart from the fact that they now are a 4 block pattern and way more road bias than the 750/16xzl. they are also a load carrying tyre for trucks, landrovers dont have the weight to make them flex like a crossply swamper/simex etc will so they dont really perform offraod as well.

guys in the hardcore USA scene ran Michies form trucks, 900/16, 1100/16, 1100/20 etc, they all went back to S/S BFG etc as they found they werent that good. this wasnt a reflection of the size, rather the construction of the tyre and using it outside its field(light weight vehicles)

the point that was brought up is whether or not skinny are better/worse than fat.

looking at a daily driver that has the same height tyre 750-10 inch is ample and does the job well. go offroading and the limiting factor will be the height NOT the width.

on road i feel the disadvantages outway the advantages for wider tyres on def/RRC and discos.

look back to the 80's when 4x4 really started to become popular world wide, tyres werent getting taller by much but they sure got wider. and we all know that the USA is a driving force behind the 4x4 industry....

i think we all know that the majority of stuff (in general, not just 4x4 market) in america is based on apperance rather than function, thats there society, yse they do lead the world in 4x4 motor sport, but very specific areas, so tyres are designed for a narrow use.

if i could have any 1 tyre for all round work it would be a 8.25r16 mich XCL, but this tyre doesnt exsist anymore....



so on a 15x7 inch rim what were the heights and widths for the q78 and the tsl 34x9?

Serg

My 130 sits 2 inch over a 110 in standard trim. That is how they come. I fitted them on 15's as that is what I had laying around. I didn't take measurements as the guys at Fourby's were letting me do this for nix, but, the 34's fitted beautifully without having to do much modding, but they will foul under full flex. Not so with the Q78's. They touched the leading arm, flares the whole lot. You would need to army cut the front guards. A spring lift wouldn't fix it, you would need to space it to limit your up travel to run these tyres. And they stuck out a heap. The 9.5 inch is the tread width and they balloon out a heap more like a tractor tyre. Looked tough, bit you would rip your panels to shreds trying to drive it. I will look at the 34's, but will still need to space-lift. They still are a pretty wide tyre.

CC

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Originally Posted by JDNSW

For almost all offroad situations the only important factors are the overall diameter of the tyre and the tread pattern - for any realistic width, you mostly won't be able to tell the difference, and pressures will make a lot more difference.

On the highway, wider tyres can give slightly better handling where they have resulted in wider track, although very occasionally the wider tyre may result in aquaplaning where a narrower one would not have. Note that if as well as wider tread we are talking lower sidewalls, these will result in slightly better handling in extreme conditions as the tread cannot get as far out of angle with the wheel. But the conditions to see the difference would probably never occur with most four wheel drives. These shorter sidewalls also make tyre and rim damage more likely in offroad conditions. But in most cases we are talking wider tread, not shorter sidewalls.

As suggested above, the wider tyres will use more fuel and cause more wear and tear, particularly on steering and wheel bearings, but again, for practical alternatives the difference will be small.

In my view the move to wider tyres is almost entirely due to changes in fashion, and has nothing to do with utility.

John

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Hi John,
That was the feeling I was getting. In order to get bigger (roleing diameter) tyres people were getting wider tyres with larger aspect ratios.

When you look at all the early photos/film of military Land Rovers and Jeeps they all had skinny, high walled tyres regardless of whether they were in the desert or the jungle. Even the military trucks have skinny tyres for there size.:confused:

My mag wheels have 7J x 16 x 33.0 Tubeless stamped on them.

Insted of going from the original 235 70 R16 the standard 245 75 R16 which is a wider tyre, I was wondering what other options are out there. Is there a 225 85 R16 or something simmilar?

How skinny can I go on my rims?

A couple of examples.

A mate in the LROCB has a vehicle set up almost identically to mine, and we used to do quite a lot of 4x4ing together when I was over that side of the country.

A) My IIA: 109" pick up, 2.25D, custom soft springs, 285/75-16 MTRs
B ) Mate's: 109" pick up 2.25P, custom soft springs (different design, but spring rates almost the same between both vehicles), 7.50x16 Wrangler TGs

Now the driver of vehicle B is probably a much better driver than me, and certainly drives with more finesse and better wheel placement.

I noticed on a number of occasions (and have video footage to prove it), that my IIA had significantly better traction. e.g.

1) Steep, loose, rocky hill. I could idle up quite smoothly, whereas vehicle B was spitting rocks out all over the place, and moving up in quite a jerky fashion as each wheel spun/stopped/spun/stopped.

2) steep, rock ledges. the MTRs consistently performed better on this type of terrain.

3) greasy tracks and side slopes - again vehicle usually got further along the track, didn't slide sideways as much, etc... (despite the fact that MTRs are not known as being a good mud tyre).

However - that said, I think on a (long distance) touring vehicle, skinny is best.

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Originally Posted by isuzurover

A couple of examples.

A mate in the LROCB has a vehicle set up almost identically to mine, and we used to do quite a lot of 4x4ing together when I was over that side of the country.

A) My IIA: 109" pick up, 2.25D, custom soft springs, 285/75-16 MTRs
B ) Mate's: 109" pick up 2.25P, custom soft springs (different design, but spring rates almost the same between both vehicles), 7.50x16 Wrangler TGs

Now the driver of vehicle B is probably a much better driver than me, and certainly drives with more finesse and better wheel placement.

I noticed on a number of occasions (and have video footage to prove it), that my IIA had significantly better traction. e.g.

1) Steep, loose, rocky hill. I could idle up quite smoothly, whereas vehicle B was spitting rocks out all over the place, and moving up in quite a jerky fashion as each wheel spun/stopped/spun/stopped.

2) steep, rock ledges. the MTRs consistently performed better on this type of terrain.

3) greasy tracks and side slopes - again vehicle usually got further along the track, didn't slide sideways as much, etc... (despite the fact that MTRs are not known as being a good mud tyre).

However - that said, I think on a (long distance) touring vehicle, skinny is best.

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Ben i dont take anything you say lightly, and much respect your imput and opinion.

some points to consider with the above:

285/75-16 are 833.9mm tall
750r16 are 787.4mm tall

thats 46.5mm difference or 23mm more clearance.

TREAD PATTERN AND RUBBER COMPOUND: how did these 2 tyres compare?

regarding my earlier post: do rockcrawelrs run water or lead shot in there tyres(fronts atleast) ?

Serg

Quote:

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Originally Posted by Col.Coleman

My 130 sits 2 inch over a 110 in standard trim. That is how they come. I fitted them on 15's as that is what I had laying around. I didn't take measurements as the guys at Fourby's were letting me do this for nix, but, the 34's fitted beautifully without having to do much modding, but they will foul under full flex. Not so with the Q78's. They touched the leading arm, flares the whole lot. You would need to army cut the front guards. A spring lift wouldn't fix it, you would need to space it to limit your up travel to run these tyres. And they stuck out a heap. The 9.5 inch is the tread width and they balloon out a heap more like a tractor tyre. Looked tough, bit you would rip your panels to shreds trying to drive it. I will look at the 34's, but will still need to space-lift. They still are a pretty wide tyre.

CC

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i am interested in both the tyres you mention so any mounted measurements you have would be a great help.

cheers, Serg

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Originally Posted by uninformed

Ben i dont take anything you say lightly, and much respect your imput and opinion.

some points to consider with the above:

285/75-16 are 833.9mm tall
750r16 are 787.4mm tall

thats 46.5mm difference or 23mm more clearance.

TREAD PATTERN AND RUBBER COMPOUND: how did these 2 tyres compare?

regarding my earlier post: do rockcrawelrs run water or lead shot in there tyres(fronts atleast) ?

Serg

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Serg - I agree all things are not quite equal, but it is about as close as you can get - 2 offroad tyres from the same company on almost identical vehicles. In reality there isn't much in the diameter difference. The TGs would have been about 32.5" and my MTRs 33.1" (measured, on the rim). In fact, because of the softer sidewalls, my tyres probably had a smaller rolling radius when aired down). Cleareance wasn't an issue either - IIA #B had a rover rear, I had a sals rear (but neither was dragging in the cases I mentioned).

I agree with you that compound and diameter are probably more important, but IME width is more than a fad in some cases and for some terrain types

When I went from 235s to 285s (with a 0.75" diameter increase) I was amazed at the difference in traction, MORE than the difference fitting a rear locker made! I think it is just down to surface area, and ability of a wide/supple tyre to deform better.

You are right that many rock crawlers run water or steel shot in (front) tyres, but they are also crazy about keeping overall weight down and C of G low. That is why they usually fit alloy wheels, and don't run anything much bigger than 37-39" tyres (C or G). The IROK tyres which were the tyre of choice for a while, were specially designed to reduce weight.

However, on my touring rig (110) I run 255/85-16 Bighorns, and don't want anything wider.