Melex · 864 · Bar
Recommended bar for a Melex 864
- 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
bar
2.31 / 2.31
32-35 / 32-35 psi · 231 / 231 kPa
32-35 psi F · 32-35 psi R · 2.2-2.4 / 2.2-2.4 bar · 231/231 kPa
European and UK handbooks usually quote bar. The Melex 864 catalogue is 2.2-2.4 bar front and 2.2-2.4 bar rear (midpoint 2.31 / 2.31). A 10 °C overnight drop takes roughly 1 psi (0.07 bar) off a closed Melex tyre.
Bar, PSI and kPa
Bar-led conversions around the Melex 864. 2.2-2.4 bar is not “32-35 divided by ten”.
| Bar | PSI | kPa |
|---|---|---|
| 2.07 | 30 | 207 |
| 2.21 | 32 | 221 |
| 2.28 | 33 | 228 |
| 2.31 | 33.5 | 231 |
| 2.41 | 35 | 241 |
| 2.48 | 36 | 248 |
| 2.62 | 38 | 262 |
| 2.76 | 40 | 276 |
| 3.03 | 44 | 303 |
| 3.45 | 50 | 345 |
| 4.14 | 60 | 414 |
Melex 864 placard versus sidewall
Sidewall PSI is a carcass maximum. Recommended operating pressure for this 864 is the pillar sticker, near 34/34 psi.
Estimated pressure by tyre size (225/45R17 and others)
Planning cold pressures for sizes often seen on a passenger car. This 864 sample opens with 225/45R17, then 225/40R18 and 215/55R16.
| Tyre size | Front PSI | Rear PSI | Front bar | Rear bar | Front kPa | Rear kPa | Note |
|---|---|---|---|---|---|---|---|
| 225/45R17 | 35 | 35 | 2.41 | 2.41 | 241 | 241 | Sport 17-inch |
| 225/40R18 | 36 | 36 | 2.48 | 2.48 | 248 | 248 | Low-profile 18-inch |
| 215/55R16 | 34 | 35 | 2.34 | 2.41 | 234 | 241 | Slightly wider 16-inch |
| 185/65R15 | 33 | 33 | 2.28 | 2.28 | 228 | 228 | Small / older car |
| 195/65R15 | 34 | 34 | 2.34 | 2.34 | 234 | 234 | Very common compact |
| 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 |
| 215/50R17 | 35 | 35 | 2.41 | 2.41 | 241 | 241 | Plus-size 17-inch |
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 | 38 psi / 2.62 bar |
How to set the 864
- Park the Melex 864 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 864 is enough to feel a pull.
- Refit valve caps and reset TPMS if the handbook asks for a relearn.
Temperature drift
Roughly 1 psi per 5–6 °C. The table uses 34 psi as a 20 °C baseline for this 864.
| 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 |
Melex notes
No special Melex exception: the 864 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 Melex 864 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 Melex sticker and this page disagree, the sticker wins.
Other Melex models
Questions about this 864
What is that in bar and kPa for the 864?
Mid-points are about 2.31 bar (231 kPa) front and 2.31 bar (231 kPa) rear.
Is the sidewall number correct on a Melex 864?
No. Sidewall PSI is a maximum. The 864 placard is the operating target, near 32-35/32-35 psi.
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 864?
Monthly, before a long trip, and after a 10 °C weather swing. Include a full-size spare.
What tyre pressure should a Melex 864 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