[christover1]

Gwagensteve wrote:

christover1 wrote:

High pressures can cause skids on wet roads also.

Hmm, I'm not convinced the physics supports this view.

Steve.

I was thinking incorrect footprint/contact to the road surely must effect water dispersion, and risk aquaplaning?
Too low could do same?
Wearing out centre of tread earlier would effect road contact, too?

[sideways]

christover1 wrote:

High pressures can cause skids on wet roads also.

FWIW, with my bartreads I've found if you stick 25-30psi in them then they stop trying to kill you in the wet and around corners, Tyre placard says 17psi and that's for 4ply tyres, mine are 6 ply.

The handling and wet weather performance were diabolical with 15 in them, in the dry the tyre would feel like it was trying to fold over. It felt like it was just going to roll if you ever tried to go sideways. In the wet you just went sideways everywhere.

[Reubs]

LOL another tyre pressure dabete - this never gets old!

I had a tyre pressure debate with some defensive driving instructors on a company supplied course a few months back. I turned up with 20PSI as per the placard in my Coily. The instructors checked everyone's pressures then told me I couldn't do practical part of the course with underinflated pressures. After much debate and a call to some 'expert' at the driving instructors office in Melbourne it was decided I needed to run a minimum of 28PSI to do the course so I had to pump the tyres up. At the end of the day I made sure I deflated my tyres back to closer to 'normal' pressures (about 22PSI warm) for the drive home, at which time the instructor even had the nerve to suggest I should look at the maximum inflation pressure stamped on the tyre's sidewall to figure out what pressure I should run (50PSI at 800kg loading)!

Apart from slightly lighter steering and a harsh ride (the course was conducted on QLD Raceways crappy back carparks) I didn't notice a huge handling improvement over 20-22PSI with the tyres at 28PSI and we were doing slaloms/brake tests/cadence braking etc, and I think even the instructor was impressed at how well the Sierra handled (mild lift with 215s and sway bar still attached) with 'supposedly borderline underinflated' tyres - it certainly outperformed all 6 of the company Hilux's in our group.

[sideways]

When this thread was first started I was going to post "inb4 tyre pressure smackdown" but I thought I wouldn't be an arse.

[speedyblue]

Kuhmo MT's come in 215/75R15 as well. No experience with them myself. I'm about to buy some AT's in this size for the wifes Jimny so I'm interested in what prices you come up with.

[lightly]

I'm a tyre fitter and don't get many jimnys in but I usually put 32psi in, two blokes said just put 28 in, I doubt there is much difference in 22 and 28 psi, saying that my brother hilux with 33's usually only runs on 28 or 30 psi.

[bohuler]

I run a workshop and every single car or 4wd tyre that I fit has the tyres fitted checked against the tyre placard for pressure and sizing. I will not put my business at risk by fitting the incorrect tyre to a car just because it was aready fitted with that tyre UNLESS I have confirmed with the customer that the tyre they want fitted does not meet the ADR for the car and will probably invalidate their insurance in an accident.
Also all car and 4wd tyres that are brought into my business for puncture repairs leave the workshop with 35 to 40 psi in them. This is clearly noted and all customers are advised to check the pressure against the recommended pressure for thier car before or after refitting.
And all customers that have tyres fitted in my shop are asked to return in a week so that I can check and re tourque the wheel nuts if needed.
People are so bloody stupid that if you don't tell them they will come back blame you for making thier car drive like shit when all you did was repair thier tyre and yes I am serious when that headgasket was a direct result of the tyre being fixed here and I want you to replace the head gasket for free now.... WTF?? Fuck off and leave me alone!
**Rant over**

Dave

[Matthew]

^^ One of the few tyre fitters who knows what they're actually doing.

[alien]

Kumho KL71 =)

[barrybanks]

In both my vehicles, if you run the manufacturers tyre placard rating, you will never get the manufacturers claimed fuel consumption.
If you run tyre pressures up around 40psi you can achieve it.

[austuff]

speedyblue wrote:

Kuhmo MT's come in 215/75R15 as well. No experience with them myself. I'm about to buy some AT's in this size for the wifes Jimny so I'm interested in what prices you come up with.

Hi, finally getting back round to deciding on this. Was sold on the KL71's as my first big read around probably about 20 different forums suggested they performed just as well as the KM2's in the mud, bit better on the tar, probably wear a bit quicker but are $100 a corner cheaper.

However my latest big read around seems there is quite a few whom feel that they do not perform as well in the mud as a KM2, don't clean well and have poor side-biters performance. Basically alot feel they are a lower mid range muddie with good road performance. Any zookers with experience with the mud performance of the KL71 and how it compares against the KM2?


KM2 VS KL71
Best prices i could find up here (Darwin not worth shipping in) are
$205 KL71
$310 KM2

Cheers

[Marko_SJ]

Get trepadors Good on road, good in mud, good on rock.

Dearer than the KL71s cheaper than the KM2s.

[atari4x4]

KL-71 =

KM2's & treps =

[sideways]

atari4x4 wrote:

KL-71 =

KM2's & treps =

[christover1]

Federal Couragias =

[Marko_SJ]

christover1 wrote:

Stockies =

[Scales]

KM2's
got them on mine in that size, they rule. spend the coin, reap the rewards, good on and offroad

[austuff]

Found 215 KL71's for $190 per fitted and balanced today, putting the pressure on with the price so low.
Was saving some more for treps, federals or km2 but very tempted to jump on these before they are gone (customer didn't pick up so going cheap)

hmmmm

[Marko_SJ]

Thats a significant saving over treps and KM 2s.

Are you going to drive the 'black shit' after it rains? If so, you want the most aggressive tyre you can find.

[austuff]

Yep, the plan is to hit the mud. Getting these and putting the savings into a electric winch is tempting like ORU9 or Runva 9500 (already have a tirfor). Just that some reviews are pretty bad when it comes to self cleaning etc, they sure look chunky enough on the outer tread though

Cheers

[austuff]

Hi, after much searching and a few let downs and an inability to source a good price for known brands I took a risk on some relatively unknowns in stock here in Darwin ($180 fitted). I think (haven't had muddies before) they are very noisy on the tar but (with a mates truck on standby) took them through some nasty crap down the creek and they pulled me out no worries, then i took them through some even nastier stuff and only just got through though didn't feel them turn to slicks at any time just needed more revs or 1st gear for that one. I like the look of them (reversed no big blue writing) look a bit like the old KM's I think.

So glad the tyre guys agreed to squeeze the 235's on to some spare 5.5" rims as that's all I had after much research this appeared to be acceptable if I don't air them up too high? They drive nice at 20/18psi anyway on the tar (albeit noisy)

Settled on the 235's as I married the auto t-case to my manual Jimny box and the gearing is only slightly higher than my AT 225's were

Some tyre banging on the top inner guard when i hit some big holes in the mud ruts so maybe will have to look at a little body lift in the near future (have the ToughDog 60mm suspension lift already) but would rather not go body lift so might see how I go for a bit first.

Deestone Mud Clawer 235/75/R15, non-directional, 8ply, no idea of sidewall though as can't find info on this size on the net.





Let you know if they disintegrate in the first year or so so you can avoid, but might be worth considering if your on a budget and can run 235's.

Cheers

[Marko_SJ]

My mate has similar in a 31 on his hilux. They work very, very well in mud. Insanely noisy on road, and its going to get worse

Can't wait to see this thing go w/ new tyres.

[got_bar_work]

They make small simex et
They would be the go for wet season

[austuff]

The_Amateur wrote:

and its going to get worse

OMG, WTF, hahaha should-ave just fitted those old tractor tyres I saw at that dump.

Actually weren't that bad but don't think I've driven them on a dry road yet so worst is yet to come no doubt

Cheers

[billythunder]

christover1 wrote:

I put 40 in newly fitted tyres, for a week, to make sure beads are nicely seated.
Maybe fitter pumped them till they seated, and left it at that.
My recent tyres had 52psi in them after fitting.

The tyre shops put higher pressure so you need to replace them sooner