Many BIMMERPOST members change their wheels for cosmetic reasons, but also to reduce unsprung weight. If BMW has its way, we could soon be seeing a massive reduction in BMW wheel weights by way of carbon fiber wheels
. The i8 has already been announced with a CFRP wheels option (pictured below), which saves 3kg / 6.6lbs per wheel
, but Autoexpress
appears to be reporting on CFRP wheels for standard non-i models.
According to BMW's lightweight construction manager, Franz Storkenmaier, "we save 25 percent in weight compared to a forged alloy wheel with the hybrid wheel [with alloy spokes and a carbon fiber rim] and another 10 percent if it’s completely carbon." Now BMW just has to convince European regulators that they’re strong enough to be safe on the streets.
For those concerned about damage to carbon fiber wheels, Storkenmaier says:
"The carbon fibre wheels are very damage resistant. They're actually more damage resistant to kerb hits than standard alloy wheels because the damage polishes out really easily. You can scratch it when you park and it's better to polish out than aluminium. You can have the metal finish to it with the alloy hybrid, but it's technically a better solution to go all the way and have a full carbon fibre wheel."
Carbon fiber wheels aren't the only component BMW is seeking to potentially produce. Others include:
Full carbon fiber steering wheel
made of a carbon skeleton and a carbon frame.
- a new carbon-plastic compound made from carbon fiber production waste from the i3 and i8 that will be a light and strong alternative to magnesium, aluminum and steel in light, semi-structural parts like dashboards, seat frames and spare wheels.
"We have tried to use the leftover raw carbon fibre from i3 and i8 production to make carbon fibre parts, mixed with plastic. We chop up the leftover fibres and mix them all together, so it doesn’t matter where they come from or what their original job was supposed to be. After we cut them up, we mix them with plastic and this mix can be used in a regular plastic-moulding machines, but it comes out stronger and lighter than any thermoplastic. We are the very first car maker to use carbon fibre on an industrial scale. Now are we able to use the leftover from the mainstream production on an industrial scale, too."
"We have developed an instrument carrier (dash structure [dashboard]) out of this material and it could replace the magnesium one at a weight saving of about 20 percent. It’s even higher for seat frames because they’re typically made from heavier metals than magnesium."
"Carbon fibre is an expensive material to work with, but if you are using production waste then it’s a different cost structure from working up raw carbon fibre. It’s cheap, and that’s how we can position it as a competitor to magnesium."
You may not be a fan of the i3, i8 or the entire idea of the BMW i sub-model, but these potential and creative uses of carbon fiber, which BMW can now produce on a mass scale due to the development of the i3/i8, can bear fruit in many other ways for future standard BMW models.