Oldtimer · Mathis · Bar

Recommended bar for a Oldtimer Mathis

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 Oldtimer Mathis 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 Oldtimer tyre.

Bar, PSI and kPa

Bar-led conversions around the Oldtimer Mathis. 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

Oldtimer Mathis placard versus sidewall

Sidewall PSI is a carcass maximum. Recommended operating pressure for this Mathis is the pillar sticker, near 34/34 psi.

Estimated pressure by tyre size (195/65R15 and others)

195/65R15 is the first planning size here. 225/40R18 is usually the plus-size or LT step. Keep load index at or above original equipment.

Tyre size	Front PSI	Rear PSI	Front bar	Rear bar	Front kPa	Rear kPa	Note
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
225/40R18	36	36	2.48	2.48	248	248	Low-profile 18-inch
225/45R17	35	35	2.41	2.41	241	241	Sport 17-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
205/55R16	34	34	2.34	2.34	234	234	Typical mid-compact OEM
225/50R17	35	35	2.41	2.41	241	241	Touring 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	34 psi / 2.34 bar	35 psi / 2.41 bar
Motorway + luggage	35 psi / 2.41 bar	36 psi / 2.48 bar

How to set the Mathis

Park the Oldtimer Mathis 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 Mathis 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 Mathis.

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

Oldtimer notes

No special Oldtimer exception: the Mathis 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 Oldtimer Mathis 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 Oldtimer sticker and this page disagree, the sticker wins.

Other Oldtimer models

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Questions about this Mathis

What is that in bar and kPa for the Mathis?

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.

Front versus rear on the Oldtimer Mathis?

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.

Is the sidewall number correct on a Oldtimer Mathis?

No. Sidewall PSI is a maximum. The Mathis placard is the operating target, near 32-35/32-35 psi.

What tyre pressure should a Oldtimer Mathis 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