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[email protected] clare@snyder.on.ca is offline
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Default Outside edge of front tires stairstepping

On Sun, 9 Jul 2017 16:07:08 +0000 (UTC), Chaya Eve
wrote:

On Sun, 9 Jul 2017 23:40:18 +1000, Xeno wrote:

To make any significant difference to your particular issue, you would
possibly need to go beyond that range.

Have a look at SAI (Steering Axis Inclination) as well. SAI and caster
angles usually increases the positive camber angle of the inside tire
and decreases positive camber angle of the outside tire during a turn
though this will depend on the steering system employed. This is a
designed in effect that you can easily and inadvertently affect when
playing around with other angles.

Unless you have a really good understanding of steering geometry, you
are playing around in the dark.


I am well read enough to know that steering geometry gets complex fast
because everything affects everything else.

The manufacturer understood the steering geometry.
The manufacturer understood the tires.

I start with their spec and stay within range.

For example, on tires, the OEM spec is considered, by most people I've
talked to anyway, as a MINIMUM spec. For example, the speed rating (S) is a
minimum spec. If I get an H-rated tire, that's "likely" to be a better tire
than that spec'd by the manufacturer (other things taken into account).


Not necessarily - if you never drive thevehicle faster than the
rating of a T rated tire.

The load range, as I recall, is 102, so, likewise, if I get a load range of
105, I'm getting a "tougher" tire (yes, I know it simply means the weight
it can carry reliably - but there's a manufacturing aspect to the sidewall
to allow it to carry that weight).


Not necessatilly - it means the tire will not overheat under the
heavier load and kighr speeds - but it does not imply the sidewall is
eny stiffer - or that the cargass is more suitable for your
application AT ALL.

To your point of exceeding the range specified by the manufacturer, if I go
to a Z speed rating or a 125 (or whatever) load range, then the compromises
start to take their toll.

Same with alignment.

Everything depends on the numbers but lets say, for the best argument, that
I'm on the high end of the positive camber range, and on the high end of
the positive toe range.

You will have tire wear problems - no ifs, ands, or buts.

It probably would be a "logical" thing to ask the alignment shop to
consider putting the camber and toe at the lower end of the positive range
if my main goal was to reduce the feathering that occurs on steep slow
downhill corners.

Does that logic make sense (to a point that isn't carried to the extreme)?

Definitely better than max toe out and max pos camber - but going
slightly to the neg camber side of the range, and possibly slight toe
IN. Tell me what year your 'runner is and I'll tell you where you
should be starting.