Eliminating bump steer?

[Greg]

How can I eliminate bump steer?

thanks

[(B1) MR_fanny]

what is bump steer if u mind me asking??

[blind_elk]

what is bump steer if u mind me asking??

As the suspension travels through from max to min, the effective length of the tie rods changes, altering the toe-in (or toe-out as the case may be). This is usually because the polygon bounded by the lower control arm, the strut, and the tie rod do not form a parallelogram.

Therefore, the solution is to create a parallelogram, usually by moving the pickup point for the lower control arm - both laterally and vertically - so that the lower control arm and the tie-rod move through parallel arcs during suspension travel.

[GTRman1992]

What is the surface condition you are getting it on ? Maybe your front suspension is too stiff and the tyres are skipping accross the top of the bumps

[Sydneykid]

I have never seen any bump steer on a double wishbone Skyline. I have a Longacre bump steer gauge that we use on the race cars. The standard geometry is pretty much spot on, you really have to get very low before it becomes an issue. In fact so low that you will have other problems far more important than a bit of bump steer. :jester:

PS; if you want to know more about bump steer this is a good simple explanation

http://www.longacreracing.com/articles/art...rt.asp?ARTID=13

[G0DF4Th3R]

i wish this thread was in English esp blind_elks post lol

no idea whats going on

[Greg]

thanks for the replies

maybe its not bump steer that i get, but when travelling over bumps/grooves in the road (usually created by trucks etc), the steering wheel gets moved quite a lot.

[SiVaK]

I think i know what you mean Greg i get the same thing when there are grooves in the road im pretty damn sure mine is the hicas playing up could be for you too

[Greg]

I've removed hicas, but thanks for the reply anyway

[GunMetalR33]

Sounds like tram lineing to me, are you running extra neg camber on the front?

I think i know what you mean Greg i get the same thing when there are grooves in the road im pretty damn sure mine is the hicas playing up could be for you too

[cul202]

My car tramlined something terrible when first I got it. From the wear on the tyres I figured it was running a shyte load of toe out. Got that taken out & some non-conical tyres & almost all the tramlining traits were gone!

Take it for a wheel alignment & see how it goes.

.

[SiVaK]

Gunmetel R33

Whats tramlining?? Im not sure about the neg camber but my tyres are worn out on the inside,is neg camber when the top of the wheel is angled outwards of the car or inwards? if you know what i mean. Cheers

[dangerous_daveo]

Gunmetel R33

Whats tramlining?? Im not sure about the neg camber but my tyres are worn out on the inside,is neg camber when the top of the wheel is angled outwards of the car or inwards? if you know what i mean. Cheers

Neg camber is where the wheels are like / that (very exagerated).

out of interest tho, I get tram lining, tracking or whatever you call it heaps, and Im only running 1* neg camber on the front. However Im running a fair bit of toe out for the street, could this have the same effect?

[cul202]

Possibly. As I said taking out the toe out on mine cleaned it up alot. But I also changed to fresh tyres at the same time as mine were down to the belts almost on the inside, while nearly new on the outside edge.

My old Torry ran 2 times the amount of camber that the 'line does and didn't track nearly as much.

.

[dangerous_daveo]

Ahh ok. It is due for a wheel alinment, and Im thinking I need more camber anyway, outsides of the tyres are wearing, and it sometimes scrubs.