[iCARMIX]

The i4 M50 is already one of BMW's most capable electric sport sedans - killer acceleration, razor-sharp handling... but here's how we took it further without going full racecar mode.
Keep the factory calipers but upgrade to carbon ceramic rotors. We're talking serious unsprung weight savings (we'll get to numbers in a sec) while maintaining daily-driver practicality.

i4 M50 front rotor size：374mm
Original weight:14.88kg
INSPEED carbon ceramic disc:6.93kg

i4 M50 rear rotor size：345mm
Original weight:8.22kg
INSPEED carbon ceramic disc:4.49kg



*Lighter brakes = quicker acceleration (every EV lover's obsession)

*Superior heat resistance - maintains consistent braking performance even under extreme conditions

*Retains OEM caliper aesthetics if you're keeping the stealth look

*Still dust-free

[ERMBA]

Trying to save weight on a 5000-lb+ compact sedan is hilarious/pointless...IMHO.

[jpuffmasterpuffpuffpuff69]

Originally Posted by ERMBA

Trying to save weight on a 5000-lb+ compact sedan is hilarious/pointless...IMHO.

Reducing rotating mass is largely a good thing, as is reducing unsprung mass. Add some light wheels, and the ride might be smoother. Efficiency will improve somewhat. Acceleration will improve a little. Nothing huge. There may be some downsides to ride, with the tire no longer absorbing as much energy from the road and instead transferring that energy into the suspension, but if your suspension is smart like many i4s have, probably not an issue.

I bet a large part replacement budget and stripping out the interior could save several hundred pounds. Seat swaps. Insulation removal. Stereo gone. Remove speakers. Or, i

[ChipXpert]

This upgrade is eye candy only.

It doesn't significantly help braking because both front and rear motors Regen.

[hotrod182]

Should show a controlled Dragy comparison before/after.What are the costs?

[knightarmor]

The cost on those rotors though..
Agreed for eye candy upgrade but if you got the $$$ why not. A good set of forged wheels would have been a better weight savings purchase though.