Fixing the ride - E85 Z4

[dan101smith]

We've got a 3.0 SE Z4 on an 04 plate.

It's got 17" wheels, and is running Michelin PS2s (non-runflats).

The problem is, the ride is still rubbish.

We're planning a week's tour of France in May, and the options are to take the Z4 or my 540. I'd like to take the Z4, but there is no way I can put up with the poor ride quality for that much driving.

So...

Fingers point to the springs and dampers.

Has anyone changed their OEM setup for anything else that has improved the ride quality?

[playalistic]

Lots of people over on the z4-forum have made changes. Are you referring to the crashy ride or the floaty feeling over rough terrain? (or both more likely )

[dan101smith]

Certainly the crashy ride.

Where is this Z4 forum of which you speak?

[Sticks.]

On 17s with non rfts the ride should be fine.

http://www.z4-forum.com/forum/

[richtea78]

Have you checked if the rear springs are broken as its meant to be a fairly common problem?

[dan101smith]

Yep, been through that already.

I've had a look on the Z4 Forum as mentioned, but all that came up in the search were threads where people said it's expected to have a st ride so deal with it.

Unless I'm missing something...

[Sticks.]

Hmm, depends what you're used to I suppose, but as I said, once the rfts are gone the ride is ok. Firm but supple, or moreso, anyway. With 17s it should be ok. Maybe see if you can try aonther one locally for comparison?

[cheadle hulme]

Mines on Eibach 30mm lowered springs, which actually improve the ride.

Much more supple and less crashy. I presume its due to them being better quality? I didn't put them on, and don't like the way it looks, but it improves ride and handling so I've left them.

[dan101smith]

Sticks. said:

Hmm, depends what you're used to I suppose, but as I said, once the rfts are gone the ride is ok. Firm but supple, or moreso, anyway. With 17s it should be ok. Maybe see if you can try aonther one locally for comparison?

Firm - yes.

Supple - no.

And that's the problem. It crashes over bumps.

I suspect it is still on original dampers now at 64k miles, but it has had new rear springs under warranty.

It's an '04 SE so if I understand correctly, it has a 30mm drop from the factory - perhaps a set of Eibach springs might be worth a try.

Trying another for comparison is a good idea - just need to find one!

[tjlazer]

If you find the ride too harsh in your car you'll have a right chuckle in the M. Sorry but this may not be the right car for you if you're having issues on 17" wheels. I did a big continental trip in my M with no issues- dont forget the roads are considerably better. Anyway the new model is popular with owners who found the old one too firm as the standard settings are a lot more pliable (if thats the right word). Personally I've decided to live with it while I'm young and buy a nice wafty merc when I'm a bit older

[R26Andy]

You find an SE on non RFT 17's a terrible ride? Perhaps a sports car isnt for you.

I have the Sport with the M suspension and RFT 18's and consider it fine (for a sports car) and much better than some of my previous cars.

Andy

[Sticks.]

R26Andy said:

You find an SE on non RFT 17's a terrible ride? Perhaps a sports car isnt for you.

I have the Sport with the M suspension and RFT 18's and consider it fine (for a sports car) and much better than some of my previous cars.

Andy

FWIW the 3.0 SE has the sport susp, but take your point. Maybe OP's isn't right.

[dan101smith]

I had a quick look over it today to check the springs aren't broken - they're not.

I also checked for any sign of leaks from the dampers - none.

The rear springs were replaced under warranty in the last 12 months, however the dampers are all originals, and now on 68k.

To the chap above - sorry, but it being a "sports car" is no excuse for a poor ride. My Boxster S was firm yet controlled, and didn't crash over every. little. bump.

I've not driven another Z4 since buying this one about 3 years ago. So I'll see if I can find one to have a go of to compare.

But I suspect a set of Eibach springs might be in order.

[Beardy10]

Bloke who I have known for many years who is Head of Sales at a big BMW dealership once described the Z4 as the worst riding BMW he'd ever driven on 18's. He reckoned it had a harsher ride than the CSL (which dates the conversation).

[pilchardthecat]

Beardy10 said:

Bloke who I have known for many years who is Head of Sales at a big BMW dealership once described the Z4 as the worst riding BMW he'd ever driven on 18's. He reckoned it had a harsher ride than the CSL (which dates the conversation).

What a load of bks. My Z4M on 18s is a much better ride than the 1 coupe i had previously (18s with runflats).

[Beardy10]

pilchardthecat said:

Beardy10 said:

Bloke who I have known for many years who is Head of Sales at a big BMW dealership once described the Z4 as the worst riding BMW he'd ever driven on 18's. He reckoned it had a harsher ride than the CSL (which dates the conversation).

What a load of bks. My Z4M on 18s is a much better ride than the 1 coupe i had previously (18s with runflats).

It was at the time the CSL came out in 2003/2004. Obviously before the 1 series existed and runflat's were just being introduced. The guy has been selling BMW's for twenty years...it's his job to sell them and he was just being honest. If you don't like it his opinion fair enough.....but it's obviously his opinion. Maybe he thinks yours is bks too........

[a11y_m]

dan101smith said:

I had a quick look over it today to check the springs aren't broken - they're not.

I also checked for any sign of leaks from the dampers - none.

The rear springs were replaced under warranty in the last 12 months, however the dampers are all originals, and now on 68k.

To the chap above - sorry, but it being a "sports car" is no excuse for a poor ride. My Boxster S was firm yet controlled, and didn't crash over every. little. bump.

I've not driven another Z4 since buying this one about 3 years ago. So I'll see if I can find one to have a go of to compare.

But I suspect a set of Eibach springs might be in order.

Personally I don't find the ride particularly crashy in my Z4 (2004 2.0i SE too). However, I've just changed back from my 16" winter wheels to 18" summers and noticed a small difference in crashiness: they look ste but 16" with 225/50/16's could be an option.

Eibachs will lower your 3.0i SE by a further 15mm. From factory we've got a 15mm drop compared to non-sport equipped Z4s, and the -30mm Eibach drop is quoted from standard (non-sport) height. I've been riding on Eibach springs with standard dampers for over 2 years and 10k miles and rate them highly. The damping control is OK with them but it's not the ultimate in control (I'd imagine something like Bilstein shocks combined with Eibachs springs would be amazing but not sure on harshness), so new dampers with springs might be an idea given your 68k miles. My Z4's only covered 29k miles in comparison.

[Steff]

I'd speak to Steve at http://www.guglielmimotorsport.co.uk/ and get it set up properly by someone who knows what they're doing.

[Sortie 10]

Take the Z4 to France - mine is on M Sport suspension and runflats, and I have driven many thousands of miles in France in my 5 years of ownership
You will notice an instant improvement to the ride quality as soon as you cross the English Channel - the reason? Simples! The French actually maintain their roads and dont just fill in pot holes, but resurface them.

There you go, solution to your problem at no cost!

[TimboZ4]

I had this problem and fitting a strut brace reduced the 'crashiness'. Mine is a 54 2.2 SE.