R. Range

Yes, I know, the title sounds kind of crazy, and I waited until this happened the second time (today, as I rarely drive my E in the rain) to post this just to make sure I wasn't losing my mind. I have 19" Iforged wheels and PS2's, and after I put them on I noticed a little vibration in the wheel at a couple of speeds, but nothing worth worrying about. However, the first time I drove the car in the rain, and again today in the rain, the car seems to shake like a wet dog above 60 mph, especially around 70. I'm not talking about steering wheel vibration; I'm talking about up through the floorboard shakes that make the passenger seat shake noticeably and that I can feel through the floor, my seat, etc. What on earth would account for this that wouldn't really be noticeable in the dry?

And while I'm on the subject of oddities, is the clearance between our brake pads and the rotor much less than a typical car? I'm thinking maybe it is to reduce the stopping time/distances or something. The reason I ask is I've noticed that the car doesn't move much (not at all sometimes) when sitting on level ground at idle with your foot off the brake, either in drive or reverse, and one time after washing the car the night before I had to give the car some significant gas to break it free of something to get it to back out of the garage. The only guess I could come up with was that perhaps the surface rust you get on the rotors when you wash the car was actually enough in that case to sort of lock up the brakes, but if that's so the clearance between pad and rotor must be incredibly small.

vraa

Do your iForged rims have lip?
The water will get in the lip, and totally screw up your balance, that's why they vibrate so much int he rain.

I've heard that there is no way to fix it

AMG BLISS

The wheel vibration you describe is very similar to what I encounter with HRE's. A little puddle forms on the inside of the wheel behind the centers and this results in the balancing being off. I don't know if Iforged does the same thing but definitely with HRE's. Mine at least.

Can't help with the oddity thing.

lowphat

I get the same thing - only in the rain, above around 70 or 80 - it scares the crap out of me when it happens because the whole front of the car feels like its going to break apart from the vibration.

My LM-5's have only a minimal lip, especially the front pair...

vraa

It's the lip.

http://www.clublexus.com/forums/arch...p/t-24213.html

medici78

I hear the only fix is to pull over and wipe off as much water with a towel. Only temporary, I'm sure.

W211 Ryda

There was a thread on this subject awhile back. I guess there really isn't any solution to this.....well....except to slow down.

https://mbworld.org/forums/showthrea...rain+vibration

R. Range

Thanks a bunch for the feedback. Now at least I know I'm not crazy.

It's funny you guys said what you did because on my way home after I posted, I started thinking about something else I had noticed about the Iforged wheels--the inside of the barrels is not flat and smooth from side to side but is somewhat concave. I figured this out because I noticed that they retain a fairly good sized pool of water in them after washing the car, and I had taken to reaching in with paper towels after I got the car dry and soaking up the pool of water. On the way home I started thinking about that and whether it's possible they could retain enough water inside the barrels to throw off the balance of the wheel (plus they do have lips, at least 3" on the rear and probably and inch and a half on the front). What a weird side effect for an aftermarket wheel.

midget fidger

This thread has been dead for a while, but my wheels seem to be having a similar issue and I'm considering installing http://www.iforged.com/store/product...?products_id=5

They're supposed to push the water out during the rain. I don't have iForged wheels, but they should fit onto my valve stem just fine. What do you guys think?

Here are the installation instructions - http://www.tpmssolution.com/tpmswaterinstall.pdf

Vic55

Dead for a while? Try 4 years.

pearlpower

Universal fit item, not specifically for or made by iForged wheels
http://www.tpmssolution.com/tpmswaterinstall.pdf

Yuille36

I definately know how this is, I had a 19" rims with a polished stainless steel lip, and water sometimes gets, behindthe lip, and throws that balance off, with a little shimmy in the steering, especially now that it's winter. During the summer months, the water would eventually evaporate, but not the winter. This is a good thing to keep in mind the next time it happens.

Full Throttle

Thanks for explaining why this occurs, i was going nuts thinking about this.

midget fidger

Yeah, I almost took the car in for road force balancing of the front wheels today ($70) until I decided to search around some more on the forums. I found a reference to this thing on some Audi board. Once it's installed, the wheels will have to be rebalanced anyhow so that saved me some hassle.

Jasoneo5

Hate to bring this back again BUT I am having the same vibration problem in the rain, only I am running the stock 18's. Coming from under the wheel wells, and I want to say the passenger side. I don't want to sound stupid but at first I thought it was the motor until reading this thread because when I sped up the vibration seemed to get a little worse.

I pulled off the freeway and the vibration stopped. Anybody?

dinfung

Bring this old thread alive. Anyone know is ther a fix or where I can buy some of this tpms divider? All the link above is dead.

Dublinoh

Go to the link in post #5, read the thread in the Lexus forum. Bottom line: "water induced imbalance" is an urban myth say two physicists and a Tirerack expert.

Onespeed55

That's not what I got from the Lexus thread at all... what I read was a couple of hypothesis with no real data to back them up. Nothing I read qualifies as a definitive answer one way or the other. Its obviously wheel/tire related, and only on certain types of wheels, so real-world data suggests the "water induced imbalance" it at least a viable theory. There is much more data to back that up just from people sharing their experiences than there is to disprove it from some doctors and a "Tirerack expert" whatever that is, emailing their thoughts on the subject. Problem -> Hypothesis -> Testing -> Theory -> Testing -> Revision of Theory -> Testing -> Prove/Disprove. None of that happened, so while I'm not saying its true, they can't possibly say its false.

If you added a 1oz weight in a random spot on your wheels and ran up to 80MPH do you think you'd notice a vibration? Now just imagine XXoz of water randomly placed inside of the wheel barrel. Regardless of whether its co-rotating or not, it surely has some sort of effect on the balance of the wheel. Moving around or stationary, its going to have an effect. The balancing machine test was one test being performed by tire shop employees, and hardly qualifies as definitive. Not saying they're dumb, but they are not physicists and the conditions were not controlled (or uncontrolled, as in the case of a car moving down a highway at 80MPH).

dinfung

Thank Dublinoh and Onespped55. The pass few day I drove over 1000km from Vancouver to Banff and back. I have driven up to 140km with no vibration in dry. While I am in heavy rain I do experience vibrations at 120km and above. I am not try to prove who is right or wrong here, but I do like to see if there are anyone who believe in this found a fix or cure.

Dublinoh

Onespeed55 Your example of a "one ounce weight at random" is counter to the argument the physics professors put forth which was the water would distribute evenly and not not be randomly placed. However your point that they did not test or observe is a valid point. Also the test that was performed on the tire balancing machine did not introduce any outside vibration, that is to say something like road vibration and suspension movement. In my minds eye (I know....) I could imagine vibration causing evenly distributed water to take on a wave like shape, think a vibrating string here, harmonics with peaks, valleys and nodes. If that occurred it would certainly cause imbalance. So the experts were describing a steady state of rotation, and real world would be rotation and road vibration, etc.. If I were to choose, I'd be in your camp.

HeissRod

Urban myth is bull****. If it's raining hard, my wheels (both front and rear) start vibrating at highway speeds like they are out of balance. If I pull off the freeway and stop at a stop sign, to let the water somewhat drain out, then pull back on the highway, I'm good for another few miles until the water builds back up.