The epitome of racing feeling in everyday traffic starts a new round. 35 years after the debut of the first BMW M3, BMW M GmbH presents the latest generation of its high-performance automobiles in the premium mid-size segment. Time to introduce the two new vehicles. In the #M3M4explained series, the developers have the floor.
First-hand information from those who know best. In the fifth episode of our series, designers Andreas and Kristian talk about all the details of the rims on the new M vehicles and answer questions from the M community.
BMW M ENTHUSIASTS ASK, BMW M EXPERTS ANSWER.
How much time does it take to design a rim?
Andreas: The development process, i.e. design and industrialisation, takes approximately half a year.
Is the 18" entry level wheel a cast or forged wheel?
Kristian: All summer wheels for the new BMW M3 and M4 are forged aluminum wheels. The basic wheel Styling 824 and the two M Performance Stylings 963M and 1000M are even completely milled. The winter wheel 829M is a cast wheel.
What is the bolt pattern? Is it the same as in the G30?
Andreas: It's 5x112. These are the new standard dimensions used by all new BMW models.
What colours are available for the M Performance wheels?
Kristian: The 20"/21" 1000M will be available in Jetblack matt and Goldbronze matt. The 19"/20" 963M is available in Frozen Gunmetal Grey for the first time.
Are they all diamond cut or are there any more durable powder-coated options?
Kristian: The surface is already so good after production that nothing needs to be recut or cut to a diamond finish. All wheels are powder-coated in series production.
How much does the lightest wheel weigh and which one of the range is actually the lightest?
Kristian: The lightest OEM wheels are the 963M weighing in 9,9 kg for the 19" (front) and 10,9 kg for the 20" rims (rear). So these 4 rims are approximately 3,5kg lighter compared to a 826M car set.
What is the actual wheel weight of your lightest 19"/20" combination?
Kristian: The factory offered 826M with track tires (option code 1U1) starts as low as 94 kg. The 963M starts at approximately 90kg including tires.
How important is the consideration of gyroscopic moments in the development of rims?
Kristian: Very important as it has a major influence on all driving-relevant parameters. During wheel development, the suspension and brakes are carefully considered.
The largest wheels are 20" right?
Andreas: The largest wheels are the 1000M M Performance accessory wheels with 20" front and 21" rear.
What is the recommended wheel style for the winter?
Andreas: There is a specific 19"/19" 829M wheel combination available with specific developed winter tires.
Does BMW make the wheels or do you use an outside manufacturer to make them?
Andreas: All BMW wheels are developed in-house and then industrialised and manufactured in collaboration with our premium wheel suppliers.
Does it have self-levelling BMW logos on every wheel type?
Andreas: These are available as accessories at your local dealer. A must for every BMW enthusiast!
Which is the best choice for daily use? Concave design or M Performance?
Andreas: Basically, all wheels are designed to work best with the car in daily use. However, it depends on the local road conditions where you drive or your driving purpose in general. On the race track, things look different again.
What is the width and offset for the wheels?
Andreas: Dimensions are: 824M: 9,5Jx18" IS20 / 10,5Jx19" IS20; 825M / 826M / 963M: 9,5Jx19" IS20 / 10,5Jx20" IS20; 1000M: 9,5Jx20" IS20 / 10,5Jx21" IS20; 829 M (winter wheel): 9,0Jx19" IS20 / 9,5Jx19" IS20
Which one of the wheels has its topology optimized to the maximum?
Andreas: Each wheel is designed and engineered to its maximum.
What's the most difficult part about designing the wheels?
Kristian: With many years of experience in wheel design and development, we always find an adequate and clever solution. Our principle is: Nothing is impossible. And if it is impossible, then we should make it happen.
Why is there no silver M Performance wheel option?
Kristian: Gold is more precious than silver ;)
Can you please elaborate on the idea behind the different size of the front/rear wheels?
Andreas and Kristian: Short and sweet, because the topic is actually very complex: As explained in Episode 03, the new staggered wheel setup enables superior dynamics compared to a conventional setup. All chassis components (axles, steering, stiffening), tires and wheels have been meticulously fine-tuned to achieve every possible optimum, virtually near the limits of physics. With the winter wheels, however, there are 19" instead of 20" on the rear axle. The advantage is obvious: you could put on snow chains in winter - safety first when drifting!
Why don't you add a rim with large outer lip to enhance the depth effect like on the old E39 M5?
Kristian: Because the brake calipers are getting bigger and bigger and thus the space for moving the spokes inwards is limited. From a design point of view: such rim flanges or outer lips also look rather dated on modern cars. On my E28, on the other hand, it fits because it is contemporary and visually correct.
How much camber is there on the new BMW M3 and M4?
Andreas: Front axle camber is -1°40", rear axle camber is -1°50".
What is your favourite old school BMW?
Kristian: BMW E28 and BMW E9.
What car do you drive?
Andreas and Kristian: G21, F54, F40, E28, C5 RS6.
What was your first car?
Kristian: A VW Passat B3 35i with 2-piece BBS wheels.
Andreas: It was a Peugeot 205 CTI.
