BMW · 123 · PSI
BMW 123 inflation in PSI (32-35 front, 32-35 rear)
- Drivetrain
- rear-wheel drive
- Body
- passenger car
- PSI F / R
- 32-35 / 32-35
- Bar F / R
- 2.2-2.4 / 2.2-2.4
psi
34 / 34
Catalogue mid-points, front / rear · 2.2-2.4 / 2.2-2.4 bar
32-35 psi F · 32-35 psi R · 2.2-2.4 / 2.2-2.4 bar · 231/231 kPa
PSI is the Imperial reading most UK motorists still see on garage hoses. For the BMW 123 the catalogue row is 32-35 psi front and 32-35 psi rear. Under-inflation cooks the shoulders of a 123; over-inflation wears the centre rib and bangs every cat’s eye.
BMW 123 placard versus sidewall
If the BMW sticker is painted over, the handbook is next. This website is a map, not a replacement VIN label.
PSI, bar and kPa
PSI-led conversions for the BMW 123 band (32-35 / 32-35).
| PSI | Bar | kPa |
|---|---|---|
| 30 | 2.07 | 207 |
| 32 | 2.21 | 221 |
| 33 | 2.28 | 228 |
| 33.5 | 2.31 | 231 |
| 35 | 2.41 | 241 |
| 36 | 2.48 | 248 |
| 38 | 2.62 | 262 |
| 40 | 2.76 | 276 |
| 44 | 3.03 | 303 |
| 50 | 3.45 | 345 |
| 60 | 4.14 | 414 |
Estimated pressure by tyre size (205/55R16 and others)
If your BMW 123 no longer wears the OEM diameter, start at the row nearest 205/55R16 or 245/40R18 and confirm with the tyre maker’s load table.
| Tyre size | Front PSI | Rear PSI | Front bar | Rear bar | Front kPa | Rear kPa | Note |
|---|---|---|---|---|---|---|---|
| 205/55R16 | 34 | 34 | 2.34 | 2.34 | 234 | 234 | Typical mid-compact OEM |
| 245/40R18 | 36 | 36 | 2.48 | 2.48 | 248 | 248 | Wide touring 18-inch |
| 205/60R16 | 34 | 34 | 2.34 | 2.34 | 234 | 234 | Taller 16-inch |
| 225/40R18 | 36 | 36 | 2.48 | 2.48 | 248 | 248 | Low-profile 18-inch |
| 195/65R15 | 34 | 34 | 2.34 | 2.34 | 234 | 234 | Very common compact |
| 215/50R17 | 35 | 35 | 2.41 | 2.41 | 241 | 241 | Plus-size 17-inch |
| 225/50R17 | 35 | 35 | 2.41 | 2.41 | 241 | 241 | Touring 17-inch |
| 225/45R17 | 35 | 35 | 2.41 | 2.41 | 241 | 241 | Sport 17-inch |
How to set the 123
- Park the BMW 123 for at least three hours (cold tyres).
- Use a calibrated gauge, not the only meter on a forecourt hose.
- Set the placard for that axle — about 32-35 psi / 2.2-2.4 bar front and 32-35 psi / 2.2-2.4 bar rear on this catalogue row.
- Recheck all four. A 2 psi miss on a rear-wheel drive 123 is enough to feel a pull.
- Refit valve caps and reset TPMS if the handbook asks for a relearn.
Load notes
Load moves the rear of a passenger car first. If the factory placard already has a “laden” column, use that instead of these sketches.
| Condition | Front (est.) | Rear (est.) |
|---|---|---|
| Driver only | 34 psi / 2.34 bar | 34 psi / 2.34 bar |
| Full occupancy | 35 psi / 2.41 bar | 36 psi / 2.48 bar |
| Motorway + luggage | 36 psi / 2.48 bar | 36 psi / 2.48 bar |
Temperature drift
Roughly 1 psi per 5–6 °C. The table uses 34 psi as a 20 °C baseline for this 123.
| Ambient | Gauge (front mid) | Bar | kPa | Note |
|---|---|---|---|---|
| −5 °C (hard frost) | 31 psi | 2.14 bar | 214 kPa | Gauge reads low; do not overfill once warm |
| 0 °C | 32 psi | 2.21 bar | 221 kPa | Gauge reads low; do not overfill once warm |
| 8 °C (UK winter morning) | 33 psi | 2.28 bar | 228 kPa | Gauge reads low; do not overfill once warm |
| 20 °C (set cold here) | 34 psi | 2.34 bar | 234 kPa | Baseline |
| 30 °C | 36 psi | 2.48 bar | 248 kPa | Do not bleed a hot tyre |
| 38 °C (heatwave tarmac) | 37 psi | 2.55 bar | 255 kPa | Do not bleed a hot tyre |
BMW notes
BMW run-flats still want the placard. Comfort settings in the iDrive do not replace the door-pillar figure on this 123.
Spare and inflator kit
A matching full-size spare on the BMW 123 usually follows the higher axle (often the rear, near 32-35 psi). A space-saver is commonly 60 psi / 4.1 bar — read that tyre’s own sidewall. An inflator kit is not a spare; check the sealant date.
If the BMW sticker and this page disagree, the sticker wins.
Other BMW models
Questions about this 123
What is that in bar and kPa for the 123?
Mid-points are about 2.31 bar (231 kPa) front and 2.31 bar (231 kPa) rear.
What PSI if I plus-size toward 205/60R16?
Keep load index at or above OEM. Low-profile sizes usually stay at or slightly above the placard. Use 205/55R16, 245/40R18 and 205/60R16 as a planning band.
Is the sidewall number correct on a BMW 123?
No. Sidewall PSI is a maximum. The 123 placard is the operating target, near 32-35/32-35 psi.
What tyre pressure should a BMW 123 use?
Catalogue reference is 32-35 psi front and 32-35 psi rear (2.2-2.4 / 2.2-2.4 bar), cold. Confirm on the door-pillar placard.
Front versus rear on the BMW 123?
This row is 32-35 F / 32-35 R. Even when they match, a laden rear can justify a higher number if the sticker prints one.
Handbook: placard · bar vs PSI · front vs rear · cold inflation