My last FWD car was a 98 Integra GSR and that car had moderate torque steer but the bump steer wasn't that bad. Now the MCS has pretty serious torque steer and bump steer. The torque steer I can handle, but the bump steer is just crazy and sometimes dangerous. If I hit a bump while changing lanes and car sometimes will jump almost 1/3 to 1/2 of a lane over in a split second! Is this normal or maybe there's something wrong with my suspension? My car is a new '10 MCS with 7xx miles on the clock, 16" wheels with the regular suspension. I've heard of alignment being off from the factory in other cars before. If this is just the nature of the car, is there something I can do to the suspension to get rid of it? Sorry in advance if this topic's been covered before.

 

First, do you still have the horrible run-flat tires on that have a too stiff of sidewall?
That's a majority of your issue as the car does like to "skip" with run-flats.

Get a normal set of tires with a flexing sidewall and your horrific scare of bump steer will go away.

- Erik

 

Yup still have the run flats, totally forgot about them. This is the first car I had with run flats, so I have nothing to compare them to. I am planning on going to 17" wheels so maybe I'll switch to non-runflats when I do.

 

Replacing the shocks with Bilstein HD's mage a very big difference.

 

on both!

 

The 17" wheels will only make the problem worse. You would be better off sticking with the 16"s. If you decide on wider tires and wheels, that will also exacerbate the issue.

Wider tires will also tramline more than narrower tires.

Koni Sport shocks or Koni FSD shocks go a long way to improving the ride and handling.

 

"made" Hate this laptop keyboard.
Anyway, the problem is still the shocks. Bump steer is not that bad and I find no bothersome torque steer. I can floor it and it goes dead straight. Note the factory alignment was way off. Maybe tires will help. I changed the shocks first and almost did not change from the RF's. ( now run re960's)

One way to have no bump steer in a strut suspension is to put the rack and steering arms in the same plane with the lower arms. Another is to move the steering to some part of the strut that does not move. Neither solution works in real cars, so they have some bump steer.

 

I put in Koni FSDs and bump steer remains horrific, absurd, dangerous. What was Mini thinking?

 

I've got no noticeable bump steer. Torque steer, yes. Bump steer, no.

Mike

 

Holy necro-thread!


The R56 has much less measurable bump steer than the R53. Almost none actually.

It sounds like you have a ball joint loose or something otherwise fairly catastrophically broken. As usual, go drive another like model that's kept in good condition and compare to yours. Instead of just assuming it's a fundamental design flaw and pointing the finger elsewhere, take some responsibility and inspect your car for improper maintenance first.

 

Damn, we must not be driving the same car.

 

Have you driven another one to determine if it's just your car? Have you checked the fastener torques and condition of your suspension? For real and not "seemed legit"?

 

Entire front end is new. Did this before and now. And others have complained of the same bumpsteer issue.

 

Sounds like the answer is no, you haven't made a direct comparison. Are you sure you're using the correct terms? Torque steer is not bump steer.

Bushings, ball joints, and tie-rod ends are all new *and* torqued correctly? If so then perhaps your problem is the rear end or something you've missed.

The fact is the R56 has minimal front bump steer, which is a measurable toe change through the suspension stroke.

 

Glad I found this thread. I also experience a huge amount of bump steer and torque steer. I do not have run flats, but have stock suspension. I was going to try a strut brace for the front end, but what I am hearing is improved shocks may improve front end control and reduce bump steer. Any thoughts on the effect of adding a strut brace and it's effect on this issue?

 

That's correct, I've never driven another R56 Cooper. But I've read posts from others complaining about the exact same issue.

Yes I understand the difference between both terms and am using the term deliberately.

 

+1. I could have sworn on several occasions, I was going to die in my R53...

 

I went from 140k miles on OEM shocks to Koni FSDs and all new bushings front (and rear), control arms (ball joints), new engine mounts and yes of course the ride is less harsh but bump steer is still atrocious when steering wheel is anything but straight.

 

That doesn't mean the R53's bump-steer is bad per se. There are plenty of other sports cars with way worse bump steer than the R53. The NA Miata for example is many times worse than the R53, yet it's almost never talked about because in the real world it's not much of a problem.

If you guys are having your cars lurch to the side simply driving down the road, then it's NOT bump steer, you have something broken or loose. If the car hits a heave or speed bump in the road, both sides of the suspension compress evenly. Whatever minor bump steer is there means you get symmetrical toe changes and you don't feel it in the cabin. If you hit an asymmetrical bump, the tire tread squirm is going to be far greater than any toe changes. Loose ball joints however, will radically shift the alignment and cause unpredictable behavior.

Don't use bump steer as a mysterious term to blame another problem on. Man up and take your cars to professional mechanics so they can accurately diagnose the problem. Why are you driving around with so-called dangerous suspension anyway? Be responsible people!

 

Thanks Lex. I should have mentioned mine is an R57, but would think that the convertible would be even stiffer structure-wise. Has about 75K on the original suspension. Would love to find an approach that resolves the issue.

 

2001f4s,

Oh thats a different vehicle. Convertibles much less rigid structure. I dont know if they have the same front suspension.

 

75k miles means your front control arm rear bushings are shot. They're usually broken by 30k miles on all MINI's and BMW's with single pivot mac struts.

 

Thanks Ryephile. I will get on it and report back.

 

The r57 platform is your issue. that car moves all over the road.

 

Mine (r56) has been the same way since new.