Re:GEN 4 Wobble

SZ4 steel wheels, red dot on tyre aligned to blue dot on wheel, all 4 the same.

facade wrote: I could be wrong, but it is no more trouble to machine the wheel round than any other shape*- at least I would machine it round, it isn't exactly hard.....

The issue isn't the roundness, its the balance. They are 2 different things. Most balancing issues are caused by the tyres rather than the rims, as they are both further from the centre and of a much more complex shape/composition than the rim.

As to whether the Gen 4 will suffer wobble issues, I doubt the tiny changes made to the Gen 4 will have eradicated the issue. All live axle vehicles suffer from wobble to a greater or lesser extent.

Micheal wrote: yes they do fit like that but I found the travel on the jack insufficient to raise the wheel of the ground, necessitating a lot of faffing around with bits of wood and then found when the jack was sitting high enough the diagonal arm would foul part of the underbody. I just wondered if this was just me or if anyone has replaced the jack with something more purposeful that would effect a swift wheel change in an emergency?
Thanks

Unless they have changed the jack from the previous Jimnys which I doubt, It sounds like you are doing something wrong. The standard jack is sufficient to lift a tyre clear of the ground, even with much bigger tyres fitted. If you are trying to jack it up under the chassis rather than the jacking point on the radius arms you will definitely have height issues though.

Busta wrote:

facade wrote: I could be wrong, but it is no more trouble to machine the wheel round than any other shape*- at least I would machine it round, it isn't exactly hard.....

The issue isn't the roundness, its the balance. They are 2 different things. Most balancing issues are caused by the tyres rather than the rims, as they are both further from the centre and of a much more complex shape/composition than the rim.

As to whether the Gen 4 will suffer wobble issues, I doubt the tiny changes made to the Gen 4 will have eradicated the issue. All live axle vehicles suffer from wobble to a greater or lesser extent.

I'm going on what I've read- the blue dot on the steel rim marks the low point of radial runout of the rim, and goes to the red dot of the tyre- the point of maximum radial runout of the carcase, so overall gives the roundest tread profile, and therefore slightly less flexing of the walls to maintain the ride on a level road, I suppose if you had high pressure tyres with stiff sidewalls the car would nod less as it goes along.
Machining the alloy at manufacture could well make it near enough to round that there is no appreciable radial runout/runin, so they don't mark the rim.

In the absence of a rim mark, you default to the yellow mark- the lightest point of the tyre, and put it next to the valve- the heaviest point of the rim, so the wheel is nearer to static balance and they use less additional weight dynamically balancing it.

Does seem a bit "wet finger in the air" though, relying on an unknown amount of tyre runout to correct an unknown (but in spec.- honest ) amount of runin at the rim.