There are many online retailers such as eBay that provide a variety of goods for sale to the public. One can find used BMW tires as well as all sorts of other goods on such sites.
The Z4 does not have as spare tire. Run flat tires are used.
can 4 people ride in a bmw 745 with 22 inch rims
No.
No
BMW 635 car tires can usually be purchased at one's local BMW dealer. If not available, one can find them at Mavis Tire, or even at Wheel Fires internet site.
You can purchase tires at any local car dealership. For example, if you own a BMW, take your car to a local BMW dealership. There, you can purchase your tires for your vehicle.
BMW X6 come standard fitted with run-flat tyres.
Low tires.
There are a variety of companies that sell inexpensive replacement tires for BMW cars. Some of these companies include Tire Rack, etyres, CARiD, Bimmerzone, and many others.
Believe it or not, you hit it with a hammer (I used a rubber mallet). For exact procedure, check out this very good DIY for BMW brakes: www.dvatp.com/bmw/diy/brakes . Good luck!
There are many stores that sell BMW tires locally, this includes Pep Boys, Michelin among others. Not all stores will carry the exact same type of tires, but most carry a variety and will help you to find ones you need if you cannot find them.