Caterham · Seven S3 · Rear
Rear axle PSI and bar on the Caterham Seven S3
- Drivetrain
- front-wheel drive
- Body
- passenger car
- PSI F / R
- 32-35 / 32-35
- Bar F / R
- 2.2-2.4 / 2.2-2.4
psi rear
34
2.31 bar · 231 kPa at the rear axle
32-35 psi F · 32-35 psi R · 2.2-2.4 / 2.2-2.4 bar · 231/231 kPa
Loaded Seven S3 rears often need the sticker’s second column, not a copy of the front 32-35 psi figure. A 10 °C overnight drop takes roughly 1 psi (0.07 bar) off a closed Caterham tyre.
Caterham Seven S3 placard versus sidewall
If the Caterham sticker is painted over, the handbook is next. This website is a map, not a replacement VIN label.
Estimated pressure by tyre size (245/40R18 and others)
Planning cold pressures for sizes often seen on a passenger car. This Seven S3 sample opens with 245/40R18, then 185/65R15 and 225/50R17.
| Tyre size | Front PSI | Rear PSI | Front bar | Rear bar | Front kPa | Rear kPa | Note |
|---|---|---|---|---|---|---|---|
| 245/40R18 | — | 36 | — | 2.48 | — | 248 | Wide touring 18-inch |
| 185/65R15 | — | 33 | — | 2.28 | — | 228 | Small / older car |
| 225/50R17 | — | 35 | — | 2.41 | — | 241 | Touring 17-inch |
| 215/55R16 | — | 35 | — | 2.41 | — | 241 | Slightly wider 16-inch |
| 225/40R18 | — | 36 | — | 2.48 | — | 248 | Low-profile 18-inch |
| 215/50R17 | — | 35 | — | 2.41 | — | 241 | Plus-size 17-inch |
| 225/45R17 | — | 35 | — | 2.41 | — | 241 | Sport 17-inch |
| 205/55R16 | — | 34 | — | 2.34 | — | 234 | Typical mid-compact OEM |
Pressure against load
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 | 34 psi / 2.34 bar | 35 psi / 2.41 bar |
| Motorway + luggage | 35 psi / 2.41 bar | 36 psi / 2.48 bar |
A family passenger car with a boot full of luggage should use the laden rear figure if Ford, VW or Mercedes printed one. Otherwise the modest steps in the load table are only a sketch for this Seven S3.
How to set the Seven S3
- Park the Caterham Seven S3 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 front-wheel drive Seven S3 is enough to feel a pull.
- Refit valve caps and reset TPMS if the handbook asks for a relearn.
PSI, bar and kPa
PSI-led conversions for the Caterham Seven S3 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 |
Temperature drift
Roughly 1 psi per 5–6 °C. The table uses 34 psi as a 20 °C baseline for this Seven S3.
| 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 |
Caterham notes
No special Caterham exception: the Seven S3 uses the door-pillar placard. Size estimates on this page only help if you have left the original load index behind.
Spare and inflator kit
A matching full-size spare on the Caterham Seven S3 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 Caterham sticker and this page disagree, the sticker wins.
Other Caterham models
Questions about this Seven S3
What is that in bar and kPa for the Seven S3?
Mid-points are about 2.31 bar (231 kPa) front and 2.31 bar (231 kPa) rear.
Should I bleed pressure after a motorway run?
No. Heat raises the gauge. Set cold only. Bleeding a hot tyre leaves it low the next morning.
How often should I check a Seven S3?
Monthly, before a long trip, and after a 10 °C weather swing. Include a full-size spare.
What PSI if I plus-size toward 225/50R17?
Keep load index at or above OEM. Low-profile sizes usually stay at or slightly above the placard. Use 245/40R18, 185/65R15 and 225/50R17 as a planning band.
What tyre pressure should a Caterham Seven S3 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.
Handbook: placard · bar vs PSI · front vs rear · cold inflation