wheel rotating noise after 19" rims upgrade

[solidgold]

Just swapped out my 18" rims and RFTs for 313 rims with PS2 tires. It looks great on my Alpine white E89. However, I am hearing more tire noises from the rear. It sounds like a rotating blade (whurr, whurr, whurr) especially more obvious at 70-100km/hr on a straight road. Also, when I release the accelerator, the sound is more distinct. Note that this is when the top is up. The sound went away when I drop the top (maybe because of other road noises that drown it out).

It may not be harmful but just so annoying.

Checked on the wheel bearings. All is in order. Balanced and rotated the tires. Noise still there. Anyone encountered this?

[Iron Man]

Did you go with a wider tire/wheel? Did the offset change? Could be a wheel rub.

[solidgold]

Yes. I moved from 225/40 R18 front and 18x8.5, 255/35 R18 rear
to 235/35/R19 front and 265/30/R19 rear. This is the BMW Z4 specs for
19" so I don't think that the tires are rubbing the wheel hub/wall. Also i hear that noise between 70-100km/hr. If they do rub, wouldn't it produce the same noise the moment you drive?

[Iron Man]

If there is no wheel rub, the offset is in spec (you didn't mention the offset above) and they are all balanced, I don't have a clue.

Did you perform a dynamic wheel balance? I've experienced a wheel shudder/vibration around 60-70mph before, had the wheels re-balanced (Hunter balancing unit I believe) and the noise went away. There was no shudder/vibration at the lower speeds.

Sorry I couldn't help you more.

[Silver-Bolt]

Try re-installing your stock wheels/tires and see if the sound goes away.

[scollins]

I've done a little digging, and I think this may be your problem:

18" Z4 E89 wheel specs:
Front: 8x18 ET 29
Rear: 8.5x18 ET 40
From here: Post by Ramius

19" Style 313's have specs:
Front: 8x19 ET 37
Rear: 9x19 ET 39
From here: For Sale post from United BMW

If we plug those specs into our handy calculator, you get:
Front: 8mm less clearance on the strut side. Your tire is also 10mm wider, or 5mm wider on each side. That may cut your strut clearance by 13mm from stock. You might be rubbing in the front.

Rear: 15mm less clearance on the inside! And your tire is also taller by 1/4" and 10mm wider overall (5mm per side). So that cuts your potential clearance on the inside down by 20mm. You might not have that much room to give, especially when going up to a larger wheel and tire diameter.

I'd take off your wheels and inspect the inside edges for any wear. You may want to chalk the tire and wheels and then drive around some and see if it wears off.

[solidgold]

I'd take off your wheels and inspect the inside edges for any wear. You may want to chalk the tire and wheels and then drive around some and see if it wears off.

Thks again. Great idea! Will try to do this and see if I can pinpoint the exact spot.

[Memphis1]

Originally Posted by scollins

I've done a little digging, and I think this may be your problem:

18" Z4 E89 wheel specs:
Front: 8x18 ET 29
Rear: 8.5x18 ET 40
From here: Post by Ramius

19" Style 313's have specs:
Front: 8x19 ET 37
Rear: 9x19 ET 39
From here: For Sale post from United BMW

If we plug those specs into our handy calculator, you get:
Front: 8mm less clearance on the strut side. Your tire is also 10mm wider, or 5mm wider on each side. That may cut your strut clearance by 13mm from stock. You might be rubbing in the front.

Rear: 15mm less clearance on the inside! And your tire is also taller by 1/4" and 10mm wider overall (5mm per side). So that cuts your potential clearance on the inside down by 20mm. You might not have that much room to give, especially when going up to a larger wheel and tire diameter.

I'd take off your wheels and inspect the inside edges for any wear. You may want to chalk the tire and wheels and then drive around some and see if it wears off.

those are the specs for the 3 series 313's, the Z's 313 are designed specifically for the Z.

solidgold, my first reaction would be to have them rebalanced, if that doesn't fix it you might have a bent rim or bubble on tire, the last and worst case scenario, you have a bad wheel bearing.

[scollins]

Originally Posted by Memphis1

those are the specs for the 3 series 313's, the Z's 313 are designed specifically for the Z.

solidgold, my first reaction would be to have them rebalanced, if that doesn't fix it you might have a bent rim or bubble on tire, the last and worst case scenario, you have a bad wheel bearing.

Ah, I thought they only offered the 313's in 1 Series and 3 Series fitments, and only 19" for the 3 Series. It could be that he ordered the Z4 313's but got E9X 313's by mistake? :

Far less technical data available over here for you new Z4 guys, unlike us E9X guys who have had a few years to compile the details....

[solidgold]

Ah, I thought they only offered the 313's in 1 Series and 3 Series fitments, and only 19" for the 3 Series. It could be that he ordered the Z4 313's but got E9X 313's by mistake?

I don't think I got it wrong here. Specifically checked the part no. and gave it to the guys who brought in tons of wheels and rims for BMW sole dealership for the local market.

Part no :

Front alloy wheels: 19x8" ET29
Wheel part number: BMW 36116787655

Rear alloy wheels: 19x9" ET40
Wheel part number: BMW 36116787656

[Manny G...]

actually sounds like a hubcentric spacer noise.. but if you're using factory wheels they should be 72.5 mm ... next guess is a re-balance

[Mr. ///M3 RD]

Originally Posted by scollins

I've done a little digging, and I think this may be your problem:

18" Z4 E89 wheel specs:
Front: 8x18 ET 29
Rear: 8.5x18 ET 40
From here: Post by Ramius

19" Style 313's have specs:
Front: 8x19 ET 37
Rear: 9x19 ET 39
From here: For Sale post from United BMW

If we plug those specs into our handy calculator, you get:
Front: 8mm less clearance on the strut side. Your tire is also 10mm wider, or 5mm wider on each side. That may cut your strut clearance by 13mm from stock. You might be rubbing in the front.

Rear: 15mm less clearance on the inside! And your tire is also taller by 1/4" and 10mm wider overall (5mm per side). So that cuts your potential clearance on the inside down by 20mm. You might not have that much room to give, especially when going up to a larger wheel and tire diameter.

I'd take off your wheels and inspect the inside edges for any wear. You may want to chalk the tire and wheels and then drive around some and see if it wears off.

+1 Great Post ! Good advise

[Memphis1]

^^ wrong info but thanks for playing the home game


im just teasing collins...

[solidgold]

Just swap out my 19" wheels and got 4 17" wheels to test. Drove for 5-6km between 40-90km/hr and noticed that the rotating sound is not present. Although I can still hear tire noise, it is mild and does not replicate what I hear on the 19". The 17" belongs to a 3-series with multiple complex spokes unlike the 313s I have. So it could also be the big blades on the 313s taking in more air flow as you drive. But at least it confirms that other parts of the car - camber, wheel bearings, etc do not have problems.

[Memphis1]

It can't be wind buffeting... Have them checked, rebalanced or for cracks or bends.