Second Hand BMW i3 Brake Discs

The BMW i3 does have conventional brake discs, but with an important caveat: because it uses strong regenerative braking to recover energy, the conventional disc brakes are used far less than on a petrol or diesel car, so the discs and pads can last a very long time and are often in excellent condition on used i3s at breakers. All variants — including the standard i3 and the i3s — have disc brakes fitted at the front; the rear brakes on the i3 are drum brakes on most variants, so if you need rear braking components, confirm with the breaker whether the car you're buying from has rear discs or drums before ordering.

The BMW i3 ran across two main phases: the original model from 2013 and a mid-life update from 2018, with the higher-performance i3s also introduced around that time. Front disc sizes can differ between the standard i3 and the i3s, and there is a possibility of changes at the 2018 update, so crossing that boundary is something you should confirm with the breaker against your specific registration rather than assuming a direct swap. Always quote your reg to the breaker so they can match the correct disc diameter and bolt pattern to your exact car.

The i3s is a higher-performance variant with wider bodywork and uprated running gear, and it is likely to have larger front brake discs than the standard i3 to suit its increased performance — running gear typically scales with power and weight, so these are not automatically interchangeable. Treat the i3 and i3s as separate fitment categories and confirm the disc diameter and specification with the breaker against your registration before purchasing.

The BMW i3 was sold with progressively larger battery packs over its life — broadly 60Ah in early cars, 94Ah from around 2016, and 120Ah in later models — and the increased weight of the larger batteries could in principle influence brake specification. However, whether brake disc specification actually changed between battery generations is something you should confirm with the breaker against your registration, rather than assuming the battery size alone tells you which disc fits. Give the breaker your full reg to be certain.

Trim level does not affect brake disc fitment on the BMW i3 — Suite, Lodge, Loft, Terra, and any other interior or equipment trim grades are cosmetic and comfort-related distinctions that have no bearing on the braking hardware. What matters is whether you have a standard i3 or an i3s, and which model year your car is, so focus on those details when speaking to the breaker rather than the trim name.

The i3 Range Extender carries a small two-cylinder petrol generator in addition to the electric drivetrain, which adds some weight compared to the pure electric version, and this could in principle affect brake specification. Whether the front disc dimensions are genuinely different between REX and non-REX i3s of the same year is something you should confirm with the breaker against your registration, as fitment rules for this category are driven by weight and power differences — quote your reg and let the breaker verify the match.