tyre pressures

[luigi]

The diference between 40 psi and 20 psi is a lot. A noticeable diference in ride and steering.
Thanks Steve. Wayne.

[gwagensteve]

That's great news Wayne.

I'll provide some context- Richard and Wayne were up at my place yesterday - and Wayne commented that his car was very harsh and tramlined badly since he'd fitted 235 75 15 KM2's.

Richard asked what tyre pressure Wayne was running, and Wayne commented "what the tyre store left them at"

To which I wittily replied "which is often whatever it takes to seat the beads"

And sure enough - three had 43 psi in them and one had 38

I guess the learning is just because the car has 20 psi on the placard, there's no guarantee the tyre fitter will ever check what the car should run before they send you out the door, which is outrageous (and frankly, dangerous) but all too common, hence my throwaway remark.

Steve.

[Richardnclark]

Wayne, As I mentioned yesterday, as a rule in my WT I run 20 psi max on sealed roads with 30in MTs, & 15 psi on gravel, rough etc Will also go lower if needed now I have more confidence off road. I find this very satisfactory. Cheers Richard

[gwagensteve]

I used to be a lot more picky about tyre pressures vs track conditions than I am now. I pretty much go straight for the number that gives the best track performance now when I air down. For my setup, that's 4 psi, but for 235's, It might be around 12psi or so.

Getting to the right number for peak performance takes some trial and error. For my car 6 psi was too much and the car behaved badly on rock (tyre bounce) but at 4psi it's all sweet.

If you carry a compressor and ratchet strap, the consequence of pushing the experiment too far is a lost bead - no big deal to re seat.

Odds are your tyres will continue to work better and better right up to the point they fall off the rims.

Steve.

[christover1]

I was surprised by the difference 1psi made. When in the sand, I dropped from 10 to 9 and it was a huge improvement.

In my Vit I have found 25 on road to be best for me.
I use 15 on fast dirt and easy trips.
10 on most harder off road stuff.
And down to 8 when I get in trouble.

I have the trailer tyres at 17 on road,
and same as car off road.

[Richardnclark]

Thanks for the reminder about the racket strap Steve. I must add one to my tool box. Cheers Richard

[luigi]

It is probably a bit unfair to blame the tyre shop in this case. Like most tyre shops parking is in short supply. My sierra was in bits in the shed. So I delivered the bare rims in a wheelbarow. The shop is very close to my house. Then I took the wheels with new tyres fitted home in my other car.
So , I suspect they reasonably assumed that I would check / adjust the pressures to suit when I put the wheels on my car.
They did give me a really good deal. The only one who needs a kick up the bum is me for being so slack. But a very wise man once said....... a kick up the bum is also a kick forwards Regards Wayne.

[Richardnclark]

Ops - racket = ratchet (senior moment!!) R