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Discussion Starter #1
I am extremely fortunate that the previous owner of my beautiful M5 saw fit to upgrade, amongst many other things, to KW variant 3 suspension. (Cheers Alan - you did a great thing!)

I'd like to 'tweak' it this weekend though as I'm not used to the Ferrari levels of stifness that it's been set to! Does anyone have a handy guide or know a good website to show me how to get to the rear suspension mounts?

:wroom:
 

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It depends what you are trying to adjust, the Variant 3 has adjustable rebound and compression (as well as height) - it's fairly easy to get to the bottom of the shocks, but to get to the tops at the rear, you have to have had access points drilled into the boot. I saw Alan's car when it was at Birds, and as far as I recall they didn't do this. At the front obviously it is more easy to get access.

I think KW suggest a fit and forget setting at the rear for compression for this very reason........
 

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I thought the adjustments where on the bottom of the shock, so therefore you lift the car and adjust it.
 

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You know - and this may seem ignorant of the installation - but you would think it would be a standard application to drill access points into the rear deck and then cover those holes with simple black snap in disks.

It would look factory - and yet still allow ease of adjustment. Even if you needed a special tool to reach the compression adjusters - how tough can this be??
 

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Jayson, you need to get to the adjustors at the top and the bottom - many coilover kits are just adjustable for rebound, which can be adjusted at the bottom (sometimes even without removing the wheels).
 

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rogbacon said:
Jayson, you need to get to the adjustors at the top and the bottom - many coilover kits are just adjustable for rebound, which can be adjusted at the bottom (sometimes even without removing the wheels).
Indeed I know the v2 is just at the bottom, but I thought with the v3 one was one the bottom and the other on the lower bottom side.

I know with the bilsteins both adjust with one knob.
 

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This is interesting Jayson, definitely not what I have been told by one of the specialists here in the UK, and to be frank have never even examined mine in great detail - sounds like I have a project this weekend! Thanks for raising the point, this could be good news for when it comes to adjusting them for track days.
 

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Would be interested in hearing the outcome as I have exactly the same for my M5.
 

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I have KW Variant 3s in my 540. Compression is on the bottom of the coilover, rebound adjustment is on the top. They recommend that you remove your rear deck to gain access to the top of the rear coilovers (which includes removing the rear seat back and base, rear-side headliners, etc).

Wrightsville Beast: You can't really drill a hole through the deck to adjust them through it as the rear speaker enclosures extend above the rear shock mounts (otherwise that's what I'd have done with my setup).

-Jeremy
 

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Discussion Starter #11
Thanks loads for that Jeremy.

Have you played around with the settings much? I'm getting the feeling that with so many adjustments available, it could be months before I get the set up just right!
 

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I think Bird's did what they hoped was a 'fit and forget' setting tuned to Alan's requirements. You should definitely have a long conversation with them about it. Better still let me know if you fancy heading down there one Saturday and we can both tackle them!

One of the other board members here is going to be doing all the tuning work on my system for me (thanks Peter!!).

Roger
 

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jerbro said:
I have KW Variant 3s in my 540. Compression is on the bottom of the coilover, rebound adjustment is on the top. They recommend that you remove your rear deck to gain access to the top of the rear coilovers (which includes removing the rear seat back and base, rear-side headliners, etc).

Wrightsville Beast: You can't really drill a hole through the deck to adjust them through it as the rear speaker enclosures extend above the rear shock mounts (otherwise that's what I'd have done with my setup).

-Jeremy
Righty o - thank you. I always wondered about that.
 

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100%Cocoa said:
Thanks loads for that Jeremy.

Have you played around with the settings much? I'm getting the feeling that with so many adjustments available, it could be months before I get the set up just right!
: ) 'Just right' is a feeling. You won't know it until you've driven it. The key is to do the adjusting gradually, and keep it even left/right, and don't adjust all the way closed or all the way open.

I actually did an extensive search - trying to find out about the proper way to do suspension tuning - the whats and whys. I didn't find much - most people don't have coilovers - and most coilover owners don't have compression and rebound adjustments. Most of the [really small amount of] information I found recommended to "go by feel", which wasn't very helpful, as they didn't describe the right feel.

In my case, I adjusted everything to what the factory says are the most common settings (1.5 turns compression, 2.5 turns rebound for the fronts, and something similar for the rears, if memory serves). For me, this produced too much squat. I noticed this in a couple ways - one was when low-speed but high-distance bumps (low speed meaning the rate at which the suspension compresses, rebounds) - like on the highway at high velocity. I was dipping too much for my tastes. Plus, what with the lower stance I wanted, my passenger rear tire was actually rubbing against the fender lip. Enter in fender rolling. This only partially solved the problem. I adjusted the rear coilovers up a little and while that was better, I still had issues. Finally, I made them quite stiff (3/4 turns compression front and rear). This is what I remain at today - though I may make it slightly stiffer when I go to a track day.

Rebound - the rate at which the car returns to it's normal ride height. The 2.5 turn setting that the factory recommends (again, iirc) as a starting point seems fine - the shocks quickly return from being compressed to their normal height. The only place where I've noticed I don't like this is for large sweeping corners. I find that while I don't dip so much, I do bounce up from each dip quite quickly - which makes my steering feel 'loose' (as I'm sure less weight is pressing against the pavement on each rebound at that precise moment). As sure-footed as this suspension is, I think it could be that much more so by slowing the rate of return - by adjusting the rebound to not react so quickly. That's on my list of things to do. : ) Keep in mind that the floaty-feel given by the relatively high rate of rebound is still quite a bit less than the stock suspension, so I'm already better than before -but still not at the perceived level of control I'm seeking for especially in those higher-speed corners.

Overall, I personally like the reduced suspension travel quite a bit over stock. The gf doesn't mind it either ("it seems sporty"). Not harsh but quite a bit more specific than stock. For reference, I'm 31, so my opinion of the comfort level of my setup may very well be different if I were older (I wanted it tight - which is what I got).

A curious note: I have notice that with the stereo off, you can actually hear the shock rebound. My passengers haven't commented though.

Much luck to you. If you're the DIY type and you need help getting the rear seat out, I can pretty much walk you through it off the top of my head (what with suspension and stereo updates, my rear seat and deck have been removed about five times).

Cheers!
-Jeremy
 

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Discussion Starter #15
Jeremy,

That is EXACTLY the kind of advice I was looking for. Thank you so much. I am very much a DIY type and have played with many cars over the years but never a BMW. The interior is so well put together that it's a little more daunting than a 'normal' car. Once I've got that bit sussed, I'm just going to tweak and tweak until the car 'feels just right' as you say. I'm only a year older than you and I like it tight too (!) but not so tight I need to see an osteopath every week!

Apparently my car is set 'about half way' on compression and 'hard' on rebound. The ride height is set pretty low but not ridiculously so. The rear rebound is set harder than the front giving the rear end a bouncy feel. Around town (have you ever driven on London roads?!) the whole ride is just plain uncomfortable. I'd prefer a more evenly balanced posture witha slower rebound.

As for the ride height adjustment, does this make much diference to the hardness of the ride in your experience? I imagine that raising it a little would make it a bit more compliant.

Cheers,
Barney.
 

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100%Cocoa said:
Around town (have you ever driven on London roads?!)
I've driven on Czech roads - but that was only in a Skoda econo somethingorother. Honestly, what with the cobblestone, I'm not sure which suspension, let alone a sport suspension, would be comfortable. : )

100%Cocoa said:
As for the ride height adjustment, does this make much diference to the hardness of the ride in your experience? I imagine that raising it a little would make it a bit more compliant.
Honestly, I'm not convinced that ride height has a lot to do with the hardness of the ride. Though to be fair it doesn't matter to me. I'll set the ride height to what I want - then I'll adjust the compression and rebound to match my preferences from there. I wouldn't adjust the height to affect the hardness of the ride even if it did make a difference.

Oh, keep in mind that when changing the ride height of the front, you're changing the angle at which the thrust arms extend from the body. The reason I say that is that the bolt that goes through the thrust arm bushings where the assembly mounts to the body of the car is designed to be torqued at load. If you change the average ride height without re-torquing the thrust arms, you're likely to 'rip' the thrust arm bushing. This usually results in 'clunking' when switching between moving backwards to forwards. You'll also notice this if you jack up the front of your car and can move the front wheel forward and back ever so slightly without affecting the steering (ask me how I know). Just 2¢ to help you on your way.

Again, good luck in your adjustments. Having the ability to affect the ride quality that much is an empowering thing.

-Jeremy
 

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Discussion Starter #17
Hi Jeremy,

Can I sak how you know (?!) about the thrust arm problem? I have an intersting squeaking noise from the LH front suspension and it clunks/ticks around RH bends. I't going into Birds tomorrow, but any info would be most helpful.

Many thanks,
Barney.
 

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100%Cocoa said:
Hi Jeremy,

Can I sak how you know (?!) about the thrust arm problem? I have an intersting squeaking noise from the LH front suspension and it clunks/ticks around RH bends. I't going into Birds tomorrow, but any info would be most helpful.

Many thanks,
Barney.
Hi Barney - sorry for the delay in returning a response.

I'm not sure about the squeaking noise - perhaps someone else can answer that. Thrust arms have been discussed quite a bit in the last month on the roadfly e39 board. A quick search sould find quite a lot of information specific to your symtoms. In my case, I get a clunk when I change directions (front/back). This has also been explained as a potential thrust arm bushing issue.

You get your issue fixed when you took it into Birds? What was the diagnosis?

-Jeremy
 

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100%Cocoa said:
Hi Jeremy,

Can I sak how you know (?!) about the thrust arm problem? I have an intersting squeaking noise from the LH front suspension and it clunks/ticks around RH bends. I't going into Birds tomorrow, but any info would be most helpful.

Many thanks,
Barney.
you sure it's not the spring on the spring perch?
 

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Discussion Starter #20
The beast has been into Birds, been given an astonishing amount of love and attention by Pinder & his team, and been given the all clear.

The noise is there but is nothing to worry about apparently - the spring moving on the perch is the most likely cause of any clicking, the squeak being the gas moving through the valves in the strut. (Are you familliar with that one Jeremy?)

Obvious when you think about it, but still slightly odd to be so much louder on one side. (I have been a passenger too, and it was distinctly louder on the N/S from both sides of the car)

Also, in answer to my own question when I started the thread (!) - I've finally heard from KW. My mail had been around the houses a bit. Turns out I needed to contact Recaro, who are their UK agents.

They did however, send me a document on how to carry out the adjustments which I've attached. You have to scroll down to the English section.

Cheers,
Barney.
 

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