18" Wheels And Tyres On Z3

[S555RGC]

Hi all,

I have come across a little issue with my z3.

I have fitted aftermarket alloys and tyres to it. They are 225/40/18 fronts and 235/40/18 rear.

I have steering wheel wobble between 35 and 40 mph. I have had the balancing checked, all wheels are straight, but I can't stop it.

I have been advised to scrub the tyres in a bit more, but other than that does anyone have any ideas or have come across this previously.

Your advice gratefully recieved,

Rhys

[mart77]

i had this on my old car.i ended up puting 4 new tyres on and getting all wheels tracked and aligned......are the tyres balanced properly?

[S555RGC]

Hi,

Thanks for the reply.

I had all 4 tyres re balanced today jus to make sure and they are now balanced correctly.

Haven't checked the tracking though as I assumed that as it wasn't pulling to either side that tracking wasn't the issue?

The tyres arent anything special they came with the set, so maybe if all else fails x4 falkens might sort it?

Regards

Rhys

[mart77]

yea mate.i put 4 falkens on mine and it was fine....as far as tracking goes,it doesnt always "pull" to one side.it can also camber the wheels....i would give it a blast round and see if its any better if not go and get it tracked properly.good luck mate

[S555RGC]

Thanks mate, appreciate the response.

I will give it a few 100 miles then check tracking, if that fails...new boots

[Stephen McCabe]

when we purchased our z3,it came with 17" wheels and the steering was awful,tramlining & the car seemingly pushed off line by pot-holes.bought 16" wheels,had tracking done and problem sorted.bigger wheels may look better but they effect the steering imho to the extent that i wouldn't entertain them.

[S555RGC]

when we purchased our z3,it came with 17" wheels and the steering was awful,tramlining & the car seemingly pushed off line by pot-holes.bought 16" wheels,had tracking done and problem sorted.bigger wheels may look better but they effect the steering imho to the extent that i wouldn't entertain them.

Agreed,

I eventually got my money back, and instead am going to invest in some better rubber as i will be track-daying the car soon.

Mods so far:

Brembo grooved and dimpled discs and pads all round

BMC carbon dynamic airbox

Weichers aluminium strut brace

Ecotek Cb-26p

Next,

Apex/Koni suspension (shocks and springs)

Nankang NS2 / Toyo Proxes

Regards,

Rhys

[Kyberlee]

Interesting topic. I've just bought a Z3 3.0 sport. I am thinking that sometime soon I would get some new wheel/tyre combos. The car currently has 17 inch wheels with 245/45 tyres. When I brought it home I noticed it following lines or grooves in the road which I thought could be down to the tyres but it was a bit scary at the time. This topic has made me wonder now. What wheel/tyre sizes are recommended? Can anybody help? Thanks

[S555RGC]

Hi,

You probably are experiencing what people are terming "tramlining" basically the car follows the indents left in the road and the wheels are grabbed almost by it. My Wife's mother has a cooper s and it is horrendous for it.

I found it happened a little with my Z3, but adding the strut brace seems to have helped alot. Also i would assume the type, width and characteristics of tyres would effect it too.

Im sure someone more knowledgeable will be along shortly.

Regards,

Rhys

[Zeddevil]

I have 18" on my Z3, when i purchased the car it had 16" on and used to tramline, it was quite scary. I too followed advice and fitted a strut brace, which helped to a certain degree, Then looking for an answer, was lead down the path of stiffer bushes, but IMHO the car would not have been like this off the production line, so decided to investigate further.

During an MOT it was noted that the rubber dust cover on one lower wish bone was broken, so i purchased new lower arms and changed them, what i noticed was that the front suspension is actually made up of ball joints, two at the hub and one arm to subframe. what i found was that the ball joints were worn and probably overall had 1mm play across them.

I also found that the suspension top mount was loose.

So i set about the change, the ball joints on the new arms are quite stiff na dt the same on the track rods and track rod ends (all got replaced), the bearing on the suspension top mount was also tightened correctly.

The up shot is that the tram-lining and steering wander has all disappeared and the car is a dream to drive.

I would suggest checking these parts out first before changing out to stiffer bushes and strut braces, all this will do is mask the issue of wear until it becomes unmanageable.

[S555RGC]

Thank you. It appeared that the wheels themselves had an inherent fault, and were sent back.

Have just picked up some BBS style 42's from a gent in Northants, they need a bit of a clean, but will be going on soon.