Can big spacers cause bumpsteer?
 

i have 25mm spacers up front and i have noticed some bump steer and i was wondering if this can be the problem?

thanks

What is you effective offset with the spacers? They aren't causing bump steer in the technical sense, but a big scrub radius increase (like putting a 25mm spacer on a stock wheel) can lead to some odd steering characteristics.

They could cause the pre-existing bumpsteer to be worse though, since it'll be acting on a larger radius, making the wheel move more, but I'd tend to agree that it's probably the scrub radius doing whatever you're feeling.

hmm.. the car is lowered and the front wheels are 19x9.5 with a +45 offset + 25mm spacer and i def got some bump steer and is very annoying. i had to lowered my sway bar about an inch but i dont think this will cause the minor bumpsteer.. i think my spacers have something to do with it..

its not bump steer, its 'tracking.' and yes, thats due to the low offset. the further away the contact patch is from OEM, the more the car will pull over uneven surfaces

i see.. i'm going to remove the spacers tomorrow and go from there. should i remove the front and back or just the front ones?

+1

just deal with it lol
i run 17x10 +10 in the front and it feels just fine. just be more cautious around rutted roads

it's kinda dangerous i was going kinda fast the other night and my car shifted about half a lane and it was kinda scary

How is your alignment? Increasing the scrub radius from stock will make the vehicle more prone to tracking etc, but with a good alignment it should not be an issue.

I run 25mm spacers (effective wheel offset of +27) and had to fight the wheel alot until I had the car properly aligned.

its good. i have the car aligned to stock settings.. im not sure if this is good or bad for my front wheel set up.

If I'm getting my math right, your effective offset is 20mm. The 45mm with the wheels only is close to stock. It would be easy to take the spacers out to check and see if this is the root cause of your problems.

With 19" wheels you don't have much tire. Thus, your tires can't 'spring' and comply to the road much either. This may be part of the problem. What tire sizes are you running?

Several threads show different alignments for different wheel diameters, you may want to check these out and consider alignment changes. Also, may sure you aren't bottoming out the suspension since it's lowered; this makes the car misbehave badly.

so i removed the spacers and the car feels a lot better.

I think you should take this as the spacers amplifying an existing problem, rather than them being the cause.

It's nice to get a good improvement, with an easy change.

Tires can also have an effect: my 'other' car was having notable tracking issues that completely disappeared when I put on new tires; same size, different brand, not worn out.

Is the rest of the suspension tight?

yea.. car feels like a stock rx7..

bumpsteer is cause when the wheel travels up you get toe in or out, the spacer just magnifies the problem because of the scrub radius change, you might have some worn out joints that don't help things either with adjustable control arms you might be able to control the bumpsteer a little bit, but you need to get your scrub radius back to a normal amount. there are some lowtech ways of checking bumpsteer.

how do i do that?