Goupil · GEM · PSI

Goupil GEM inflation in PSI (32-35 front, 32-35 rear)

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

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

If a GEM owner asks “what PSI?”, start at 34 at the steering axle and 34 at the rear, then confirm the placard. Under-inflation cooks the shoulders of a GEM; over-inflation wears the centre rib and bangs every cat’s eye.

Goupil GEM placard versus sidewall

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

PSI, bar and kPa

PSI-led conversions for the Goupil GEM 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 (225/45R17 and others)

225/45R17 is the first planning size here. 245/40R18 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
225/45R17	35	35	2.41	2.41	241	241	Sport 17-inch
215/50R17	35	35	2.41	2.41	241	241	Plus-size 17-inch
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
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
205/60R16	34	34	2.34	2.34	234	234	Taller 16-inch
195/65R15	34	34	2.34	2.34	234	234	Very common compact

How to set the GEM

Park the Goupil GEM 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 GEM 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	37 psi / 2.55 bar

Temperature drift

Roughly 1 psi per 5–6 °C. The table uses 34 psi as a 20 °C baseline for this GEM.

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

Goupil notes

No special Goupil exception: the GEM 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 Goupil GEM 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 Goupil sticker and this page disagree, the sticker wins.

Other Goupil models

G5 G1 G4

Questions about this GEM

What is that in bar and kPa for the GEM?

Mid-points are about 2.31 bar (231 kPa) front and 2.31 bar (231 kPa) rear.

How often should I check a GEM?

Monthly, before a long trip, and after a 10 °C weather swing. Include a full-size spare.

Front versus rear on the Goupil GEM?

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.

What PSI if I plus-size toward 245/40R18?

Keep load index at or above OEM. Low-profile sizes usually stay at or slightly above the placard. Use 225/45R17, 215/50R17 and 245/40R18 as a planning band.

What tyre pressure should a Goupil GEM 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