AlBundy

iTrader: (2)

When setting toe should I be taking into consideration the play in the suspension/steering?

gigaplex

iTrader: (2)

On a FWD car like the Tamiya minis it's usually a consideration. For 4WD touring cars it's probably not as relevant.

jlfx car audio

iTrader: (37)

I do on my tc
I push my wheels in and out with same tention and read both values and figure my avg toe angle (camber,caster also) cause under acceleration the wheels will pull forward and under breaking they will pull back so I make sure both sides have same slop so car acts consistent

GuyIsDamGood

I thought the Front Wheels will pull a-bit back under acceleration.....?

jlfx car audio

iTrader: (37)

Both front and back do I'm sure

old_dude

iTrader: (1)

They pull forward.

theproffesor

iTrader: (66)

That's called bump steer and can be adjusted by adding or removing shims under the steering arm ball stud.

scirocco14

iTrader: (5)

Front wheel drive cars will toe-in under acceleration (or reduce static toe-out). Actually so will the front of the touring cars.

Now this is slightly complicated by any bumpsteer in the suspension, as the front of the car will lift under acceleration. So there are several factors involved in this.

Mark

AlBundy

iTrader: (2)

Thanks for the insight.

GuyIsDamGood

I'm looking back at this Front Toe topic. (my Tamiya M-06 is having steering problems)

Thanks gigaplex, jlfx car audio, scirocco14, and theproffesor for the info.

-I looked (looking deeper) into the Bump Steer concept.
-I have to check those Tie-Rods. I was sure it's a Servo problem (not ruling it out yet); but I'm going to check those lengths first.

-I'm also going Shim the Steering Knuckle - C-Hub area to take-out the play.
-Then I'm go'n to take-out some front Droop.

Thanks

glennhl

iTrader: (16)

I always thought bump steer was not due to sloppiness of the suspension. I thought it was purely from the geometry. When you compress the suspension, the suspension arm and steering block move up relative to the steering rack, thus the steering tie rod moves through a radius but so does the suspension arm. If both the suspension arm and the steering tie rod are the same length, then there shouldn't be any bump steer or at least very little bump steer. That's really simplified, but car designers strive to have zero bump steer, but it's almost impossible in every case.

GuyIsDamGood

Hey glennhl; what you said sounds right (unless we're missing something).

I fixed the steering​ problem with my Tamiya M-06...? It was the Servo Arm position. I moved it a few degrees on the Servo.

Take Care

Skiddins

Think it relates more to their angle (steering hub and arm) relative to eachother, as their mounting points are so different.
Most manufactures default setups tend to aim for neutral bump steer. But it's useful to be able to set it to give toe in or out depending on what you're trying to achieve with the setup.
It has the most effect mid corner.

For setting up, I tend to tap the centre of the car on the top deck to make the suspension compress slightly and return to it's 'settled' position, then check toe and/or camber etc. Make changes to links, then repeat.

If you try to remove all the slop in an RC car you'll end up with something that is undriveable.

glennhl

iTrader: (16)

You are right, not only do the lengths of the suspension arm and the steering link need to be the same, but their angles need to be close. That way as they rotate, they stay the same relative to one another. Good catch!

I also tap the suspension to settle it before measuring toe, but now you guys have me thinking that I need to check toe as I hold the suspension down in order to see what kind of bump steer I have. Of course, it's just for information purposes, because I really can't change it.

gigaplex

iTrader: (2)

Adding or removing shims under the steering link outer ball stud will alter the bump steer.