Toe-in or Toe-out?

Regards

In article , Steve writes

This is surprising.

Steering movement is distorting a parallelogram, (or at least a trapezium). If front wheels are parallel and turn together, at least one of the two angles will not be tangential to the radius of the turn, assuming the line through the back axle remains on a radius. One would thus expect toe-out to be almost universally preferable to toe-in.

Is there something about series Landys that belie this?

Regards,

Simonm.

The tracking (toe-in toe-out) don't affect the steering angles in a turn this is controlled by the Ackerman principal If you draw a line from the point of swivel on the front axle through the centre of the track rod end and extend it back they should intersect at the diff and it's the angle of the steering arms that alter this

As an apprentice I was taught that rear wheel drive vehicles had Toe-in and front wheel drive vehicles had toe-out this is because of the free play in steering components with a rear wheel drive vehicle the front axle pulls the wheels along forcing them outwards on a front wheel drive the wheels will try to drive themselves inwards

now the problem with 4X4s is are the front wheels pushed along or do they pull the vehicle

personally I tend to set most vehicles to as close to parallel as possible

Andy

In message , Steve writes

To be honest, the easiest *estimate* is based on your transmission - full time 4wd use RR settings, series (part time) use series settings ... as others have said, parallel might be good ...

In article , Andy.Smalley writes

I guess you mean the rear axle diff? Surely this is independent of the actual degree of parallel-ness of the wheels. If you turn left, does the left axle twist round more than the right one because it's on the smaller radius? It ought to, for sure.

I think I get an idea of what you're saying - I'll try to read up some more on it too

And what about vehicles with four wheel steering :) ?

Regards,

Simonm.

Parallel then - and keep an eye out for strange (and accelerated) tyre wear.

Thanks, Steve

In article , Andy.Smalley writes

Absolutely. Thanks for making it very clear (and sorry to other readers if I've been a bit dense).

It's what one would hope - all the wheels are tangential to their radii about the centre of the turn, which is itself aligned with the rear, rigid axle.

Done that way there theoretically wouldn't be any requirement for 'toe' at all, so we're back to the problem of 'pull' versus 'push'.

I was thinking about cars, but the principle you describe above is universal I guess.

Thanks for the explanation.

Regards,

Simonm.

Toe in or out has nothing to do with the angles the wheel turns when steering. It is usually to correct for the tendency to turn caused by the camber angle, that is, the amount the wheel is off vertical (usually out at the top). Series is listed as 1.5 degrees camber, and hence toe in of

On or around Sat, 15 Nov 2003 09:50:58 -0000, "Steve" enlightened us thusly:

parallel, and keep an eye on the tyre wear. Toe-out is bad, makes the steering vague on the road, IMHO. toe-in will get you heavy steering and more drag.

which reminds me, I intended to tweak mine in a tad, as there's slight evidence of inner edge tyre wear - though permanent 4x4 and the slippy-diff in the middle make it more prone to wear anyway.

On or around Sun, 16 Nov 2003 09:48:41 +1100, JD enlightened us thusly:

mine, with full-time 4x4, would handle like a pig and wear its tyres out. it was last set parallel, and looks to be causing *slight* inner edge wear, when I change the tyres front-to-back, I'll possibly tweak it slightly.

on which subject...

in switching tyres front-to back, what are the views on swapping tyres on one side, or diagonally?

tyre wear patterns seem to indicate that the NSF gets the most wear and the OSR the least, by a small margin, so to correct tyre wear, swapping 'em diagonally would be optimum. However, this gets them all running the other way to the way they started, which may accelerate wear until all the tread blocks are slanted the other way?

anyone tried it, and got any results?

Talking about bi-directional tread patterns, of course.