[Weut]

Hi,

I have the standard rims on my bmw 435d, which I don't really like, but they work. When I bought the car, I also got the M2 rims, replica's however, which are way better looking.
Now, when I bought the car, the seller told me these rims don't work on the car because of xdrive, which I didn't understand, because as long as they have around the same circumference, it should be fine, right? Atleast that's what we thought.
The original tires are 225/50/R17. The M2 ones are 225/40/R19 and 255/35/R19 on the rear. Theoretically, they should fit. It should work. But at around 50 km/h, but real obvious at 70 km/h, the car starts vibrating back on forth, which is obviously the xdrive trying to correct something.
So we thought there's probably some wear on the tires which is causing this.
Since we wanted to confirm this, we actually measured the circumference of the tires. The results were weird, because the replica's differed just 1mm front to back, while the standard BMW rims differed 12mm. side to side they were all the same.
We expected this to be vice versa, so we just do not know what to think at this point.
Can anyone here tell me what other possibilities or reasons we might have missed. And is there a solution, because I really really want those replica's on my bmw. Having the originals on there just feels bad.

[alohasurftoad]

225/40/19 255/35/10 are the standard oem tire sizes for staggered rims on x-drive. so the tire sizes are fine.

vibration is usually caused by balance. so it could be as simple as one or more wheels are not balanced.

if balance is not the problem, depending on the tire quality or wear, on or more tires could be out of round(aka tire run out). what is the brand and model of tire you are using?

also replica(cheap) rims are typically gravity cast, may balance just enough to meet spec and are easy to warp or get out of round as well (aka rim run out). if the rim is not true, the tire will not wear true as well.

i have never been a fan of replicas, cheap wheels and tires for this reason. especially on medium or high performance cars.

imo, your vibration is being caused by tires, replicas or a combination of the two.
.

[Weut]

So,
I just found out there's water in 2 of the tires. Probably from a compressor.
Chances are that is the problem. Fingers crossed!
I'm not a fan of replica's either, yet they've been giving to me for free together with the car. Here's to hoping they're not too cheap, so that they'll last for a bit.
The tires are Michelin sport 3, they seem to be close to new, which I am very happy with. Cheap tires I would never use, since I've had one accident in whole my life, all thanks to cheap tires. Grip can safe your life.