Michelin PSS on 135i with Stock Suspension

[SixBanger]

Originally Posted by cbl117

This!...like a million times. Be warned OP...changing just the tires without touching the stock msport suspension is a trainwreck. You will expose the weaknesses and introduce new ones. Car will feel floaty, steering will be touchy and you will get a feeling of excess body roll with the slightest input.

I have M rear sub frame bushings, and front lower control arms. I'm still encountering the "floaty" feeling and I' like to know what I need to do to get rid of the floating feel and shitty steering? Whats the solution? Thanks
Myles

[champignon]

Originally Posted by SixBanger

I have M rear sub frame bushings, and front lower control arms. I'm still encountering the "floaty" feeling and I' like to know what I need to do to get rid of the floating feel and shitty steering? Whats the solution? Thanks
Myles

I wish I knew what people are talking about when they complain about a "floaty" feeling and "shitty steering." I have none of that after I ditched my RFTs in favor of Michelin PSS tires in the stock sizes on 18" wheels on my 2013 135i. It has previously been suggested in this thread that this is wheel size dependent, or may have been effected by some sort of change in the suspension with the change over to the N55 engine.

Either I simply don't find what you are reporting to be a negative, or it simply isn't present to any degree in my particular vintage car with my particular wheel size. But then, I wasn't looking for a race car, I was looking for a comfortable small 2 door sedan/coupe that drives like an old style BMW. And with the PSS tires, I found it.

[SixBanger]

Originally Posted by champignon

I wish I knew what people are talking about when they complain about a "floaty" feeling and "shitty steering." I have none of that after I ditched my RFTs in favor of Michelin PSS tires in the stock sizes on 18" wheels on my 2013 135i. It has previously been suggested in this thread that this is wheel size dependent, or may have been effected by some sort of change in the suspension with the change over to the N55 engine.

Either I simply don't find what you are reporting to be a negative, or it simply isn't present to any degree in my particular vintage car with my particular wheel size. But then, I wasn't looking for a race car, I was looking for a comfortable small 2 door sedan/coupe that drives like an old style BMW. And with the PSS tires, I found it.

Car doesnt feel safe under spirited driving and normal daily driving. I'm hoping I can get rid of it by changing to coilovers.

[Esteban]

Originally Posted by SixBanger

Car doesnt feel safe under spirited driving and normal daily driving. I'm hoping I can get rid of it by changing to coilovers.

I've heard that as well from a few members with the PSS tires that are driving 2011+ 135s on stock suspension. I also know of members with 2011+ cars on stock suspension and the PSS tires that are perfectly happy. Guess it's an individual thing.

[champignon]

Originally Posted by SixBanger

Car doesnt feel safe under spirited driving and normal daily driving. I'm hoping I can get rid of it by changing to coilovers.

I just did 155 miles on mostly twisty turny 2 lane mountain roads with dashed line passing areas (which I used quite a bit, going up to around 90 mph for brief periods), plus took all the curves at 15+ mph above the speeds shown on the advisory signs. At no time did I feel the slightest bit unsafe or at risk of losing any element of control over the vehicle. Perhaps that is not spirited driving in the mind of some, but it is about as spirited as my driving gets where I live.

[BMW135pls]

Originally Posted by SixBanger

I have M rear sub frame bushings, and front lower control arms. I'm still encountering the "floaty" feeling and I' like to know what I need to do to get rid of the floating feel and shitty steering? Whats the solution? Thanks
Myles

It's the stock dampers. They take too long to settle after bumps or weight transfer. This leaves the chassis bouncing around on its springs which gives the floaty feeling. What is your alignment like, particularly the front?

Originally Posted by champignon

I wish I knew what people are talking about when they complain about a "floaty" feeling and "shitty steering." I have none of that after I ditched my RFTs in favor of Michelin PSS tires in the stock sizes on 18" wheels on my 2013 135i. It has previously been suggested in this thread that this is wheel size dependent, or may have been effected by some sort of change in the suspension with the change over to the N55 engine.

Either I simply don't find what you are reporting to be a negative, or it simply isn't present to any degree in my particular vintage car with my particular wheel size. But then, I wasn't looking for a race car, I was looking for a comfortable small 2 door sedan/coupe that drives like an old style BMW. And with the PSS tires, I found it.

You just changed over to the NRFTs, you are still getting used to them. Give it a few months and you should know the limits of the chassis. The linear rear springs probably help a small amount, but the dampers are still RFT rated, so they underdamp on normal tires, especially PSS. You'll feel the effects of this very clearly at 100mph+, less so at lower speeds, but still there.

[champignon]

Originally Posted by BMW135pls

You'll feel the effects of this very clearly at 100mph+, less so at lower speeds, but still there.

Granted, you may track your car, which I don't, so that could be an issue.

Don't know where you live, but where I live, if they catch you going 100 mph, you can forget about your driver's license for quite a while.

[Cavpilot2k]

Originally Posted by EvenEsteban

I've heard that as well from a few members with the PSS tires that are driving 2011+ 135s on stock suspension. I also know of members with 2011+ cars on stock suspension and the PSS tires that are perfectly happy. Guess it's an individual thing.

Mine feels great ([I]almost[I] stock 2011+ suspension), BUT I have bushing inserts, which have stabilized the car significantly. I used to worry about the back end jumping around on uneven pavement in a high speed turn (onramp), but the inserts did away with that.

The PSS have made the ride far more compliant over potholes and bumps and don't cause that crash feel when you hit one that the RFTs did, but to me it feels much safer and more stable at high speeds than with the RFTs. But again, I think this is due to the bushing upgrade, which I think is a mandatory mod for this car (inserts or bushing replacement).

[SixBanger]

Originally Posted by BMW135pls

It's the stock dampers. They take too long to settle after bumps or weight transfer. This leaves the chassis bouncing around on its springs which gives the floaty feeling. What is your alignment like, particularly the front?



You just changed over to the NRFTs, you are still getting used to them. Give it a few months and you should know the limits of the chassis. The linear rear springs probably help a small amount, but the dampers are still RFT rated, so they underdamp on normal tires, especially PSS. You'll feel the effects of this very clearly at 100mph+, less so at lower speeds, but still there.

I've been on the non-run flats for many years now, I'm on my second set of PSS's and the suspension sux. I'm going to try the dampers first.

[lowbudgethero]

Originally Posted by SixBanger

I've been on the non-run flats for many years now, I'm on my second set of PSS's and the suspension sux. I'm going to try the dampers first.

Originally Posted by SixBanger

Car doesnt feel safe under spirited driving and normal daily driving. I'm hoping I can get rid of it by changing to coilovers.

ya'll need to drive crappier cars to appreciate how good the 135i is

I'm OK with how the car drives now with harder sidewall tires + rear subframe inserts. The suspension is pretty soft in general though.

[BMW135pls]

Originally Posted by lowbudgethero

ya'll need to drive crappier cars to appreciate how good the 135i is

My 135i on stock dampers has a similar bump response as my 1 ton utility truck on 275k mile factory dampers that are totally beyond shot and need replacement, as far as recovery time and bump steer is concerned. Ride quality and body roll is still better on the 135i though, but I mean it's 1/3rd the weight so...

Having driven quite a few vehicles, and as someone who is maybe an above average driver and likes to push the limits of traction, the 135i is certainly NOT the worst driving car on the road by FAR, but the stock suspension parts are definitely not as good as they could be. They're definitely the weak link in the build if you made the switch to real tires.