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Hello guys,

This is my first post here I bought an 05 E85 a month ago with;
18inch (measure at 19) M6 replicas the tyres are as followed.

front - kumho ecsta supra 225/40/18
back - excelon performance uhp 225/40/18

It also came with;
16 inch stock rims with run flat Bridgestone tyres on.

(both measure 225 width)

However since getting to know the car and how it drives, I have noticed a glaring problem with the handling. Essentially on roads especially uneven country ones, the car appears to weave randomly making me fight it. I have just put on the stock rims and all of these problems have disappeared and i can drive the car how I imagined it should drive.

The problem is that I much more prefer the look of the m6 rims and was wondering if this sort of problem is down to the wheels being lower and offset or the tyres on these rims. I'm not an expert and I just wanted to know if anyone had any advice or experience with a similar problem.

Thanks for any help and best regards!

The tyres may have rotation markers on the side wall make sure they are correct

Hi Mark, they do have the markers and were correct.

Welcome to the whacky world of tramlining!
It's a common problem for lower profile tyres. Not all brands though!
I've just put my summer wheels back on ; 108's with 225 and 255 section tyres and i've gone from the sublime, staight-as-an-arrow comfort that my winter 225x55 R16 tyres gave, back to tramline city!
i've had no problems on 3 cars with 225x40xr18 vredestein ultrac sessantas but sadly these are no longer in production and existing stock is thinning.
On the lookout for some decent non-tramlining rubber now....

Have you tried reversing the 18inch set front to back & trying ?
You really need to reveal the wheel widths & offsets to get to a true answer

I previously had a 2.5SE on 18" M6 wheels. square set up with 225/40's all round and that handled absolutely fine.

it was lowered on FK springs which bottomed occasionally over large humps but the wheel set up should be fine.

[IMG]http://i1014.photobucket.com/albums/af2 ... 029089.jpg[/IMG]

[IMG]http://i1014.photobucket.com/albums/af2 ... b16c19.jpg[/IMG]

Chris_D wrote: ↑Sun Apr 23, 2017 6:35 pm Welcome to the whacky world of tramlining!
It's a common problem for lower profile tyres. Not all brands though!
I've just put my summer wheels back on ; 108's with 225 and 255 section tyres and i've gone from the sublime, staight-as-an-arrow comfort that my winter 225x55 R16 tyres gave, back to tramline city!
i've had no problems on 3 cars with 225x40xr18 vredestein ultrac sessantas but sadly these are no longer in production and existing stock is thinning.
On the lookout for some decent non-tramlining rubber now....

Hi Chris,

That gives me more comfort that the problem is likely down to the tyres. Hopefully this is something I can fix or at least lessen the effect of with a decent pair of rubbers. Cheers!

mr wilks wrote: ↑Sun Apr 23, 2017 6:36 pm Have you tried reversing the 18inch set front to back & trying ?
You really need to reveal the wheel widths & offsets to get to a true answer

Hi Wilks,

No that didn't cross my mind but I will give it a try!
Cheers!

Number5 wrote: ↑Sun Apr 23, 2017 9:02 pm I previously had a 2.5SE on 18" M6 wheels. square set up with 225/40's all round and that handled absolutely fine.

it was lowered on FK springs which bottomed occasionally over large humps but the wheel set up should be fine.

[IMG]http://i1014.photobucket.com/albums/af2 ... 029089.jpg[/IMG]

[IMG]http://i1014.photobucket.com/albums/af2 ... b16c19.jpg[/IMG]

Hi 5,

Hopefully this is something I can fix with a better set of tyres. Can you recall the brand of your 225/40's?
Cheers!

From this photo it looks like when I bought it they were "Milanza", but i know I put Falkens (probabaly 452's) on and I had no tramlining
[IMG]http://i1014.photobucket.com/albums/af2 ... 10feb9.jpg[/IMG]

My new setup with 225/40 front & 235/40 rear (MV2 wheels) rides fine without tramlining...

I would suggest the ditch finder rear tyres wont be helping things buddy, but as others have suggested check the width and offsets to check they are not staggered and fitted incorrectly.

Next try tyre pressures try 34 front and 36 rear.

If that doesn't work check RTAB & Lollipop bushes for play and movement.

If they are fine switch to a set of 4 matching good quality tyres and try that

As hopz says a good quality set of 4 matching tyres will help, Id recommend Goodyear Eagle F1s or Michelins, and get tracking done, and then check suspension component bushes as worn ones affect handling negatively.