Citroen SM Tires

Citroen SM uses two tire sizes across its production run. The 1972 Citroen SM uses 195R15, while 1973 and 1974 Citroen SM models use 205R15. Both listed sizes are radial designs built for 15-inch rims, so the main fitment difference is tire width and year application rather than a wheel-diameter change.

That means the first step is identifying the exact model year of the Citroen SM and then checking whether the car still carries the proper wheels for that year. Cars that have been restored, modified, or fitted with replacement wheels over the years should be checked carefully, since a later-size conversion can make a year-only lookup misleading.

On a Citroen SM, 195R15 is an early metric radial size. The 195 indicates a nominal section width of 195 millimeters, the R designates radial construction, and the 15 is the rim diameter in inches. Unlike modern metric sizes with an aspect ratio such as 205/75R15, this older Euro-metric style does not show the profile number in the code.

That matters because a modern buyer may expect more numbers than the sidewall actually carries. When replacing tires on a 1972 Citroen SM, match the complete size code and the 15-inch rim requirement rather than trying to substitute by appearance alone, especially on a car whose handling character depends heavily on proper tire dimensions.

The listed Citroen SM tire sizes both use 15-inch rims. The available 205R15 products are built for 15-inch wheel diameter, and the model’s year-to-year change is from 195R15 in 1972 to 205R15 in 1973 and 1974 rather than from one wheel diameter to another. In practical terms, the wheel stays 15 inches while the tire size changes.

Even with the same rim diameter, the correct size still depends on the year of the Citroen SM. A quick check of the wheel markings, an existing tire sidewall, or period service information can help confirm whether the car remains in its original configuration before a replacement tire is selected.

The correct Citroen SM tire size is tied directly to model year in the listed range. A 1972 Citroen SM uses 195R15, while 1973 and 1974 Citroen SM models use 205R15. All of these are 15-inch radial sizes, so the key point is matching the year and the actual wheel-and-tire setup on the car.

Start with the car’s model year, then compare the sidewall on the existing tires and the wheel diameter on the car itself. That extra check is worthwhile on a collector Citroen SM because many cars have seen tire substitutions over time, and a previous owner’s choice may not reflect the correct fitment for the chassis year.

The available Citroen SM products in 205R15 include both blackwall and wide whitewall sidewall styles. The Avon 205R15 radial is a blackwall tire, while the Phoenix 205R15 is offered with a 2.50 inch whitewall. Those options give later Citroen SM owners a choice between a more restrained appearance and a more stylized period look.

Sidewall style should be chosen with the car’s intended presentation in mind. A blackwall generally suits a factory-like touring appearance, while a wide whitewall creates a more customized visual effect that may appeal to owners building a distinctive show car rather than a strict year-correct restoration.

The currently listed Citroen SM tire options are from Phoenix and Avon. Phoenix offers a 205R15 wide whitewall radial, while Avon offers a 205R15 blackwall radial in the Turbosteel line. Both are radial products for 15-inch applications, but they differ in appearance and series type.

Brand choice on a Citroen SM usually comes down to the look you want and how closely you want to align the car with a particular restoration or touring goal. Once the correct year-specific size is confirmed, compare the available sidewall style and tire series to decide which option best suits the car’s intended use.

A stored Citroen SM should be kept in a cool, dry, dark space with the tires away from direct sunlight, ozone sources, and petroleum contamination. Clean concrete is acceptable, but the car benefits from a stable environment and regular attention to inflation pressure so the tires are not left underinflated while supporting the vehicle’s weight for long periods.

If the Citroen SM will sit for extended periods, move it occasionally to change the contact patch or support the vehicle in a way that reduces continuous load on one section of each tire. Collector tires tend to age more from time and environment than mileage, so storage conditions have a major effect on long-term service life.

Tires on a Citroen SM should be inspected before any meaningful drive and at regular intervals even when the car is used lightly. Look for sidewall cracking, tread separation, impact damage, irregular wear, valve-stem deterioration, and pressure loss. On a low-mileage collector car, problems can develop from age and inactivity long before the tread appears worn out.

A practical routine is to give the Citroen SM a visual check each time it leaves the garage and a more thorough inspection several times a year. If the car has been parked for months, inspect the tires closely before road use, since flat-spotting, slow leaks, and age-related cracking can affect both ride quality and safety.

Citroen SM tires should be replaced when age, cracking, hardening, bulges, persistent vibration, or other structural concerns appear, even if the tread still looks usable. Collector-car tires often age out before they wear out, especially on vehicles driven only seasonally. Tread depth alone is not a complete measure of serviceability on an older grand touring car.

The practical rule is to treat visible age or structural change as more important than remaining tread on a Citroen SM. If a tire’s history is unclear, or if the car has sat for years, have the tires evaluated carefully before regular road driving so replacement decisions are made on condition rather than appearance alone.

The listed Citroen SM fitments show a year-based change rather than one single tire size across the full production run. A 1972 Citroen SM uses 195R15, while 1973 and 1974 Citroen SM models use 205R15, and the available products shown are radial tires. That establishes the year-correct size family but not a single universal original-equipment brand across all examples.

For restoration work, the important point is to match the tire size to the exact year of the Citroen SM before worrying about appearance details. Owners pursuing concours-level accuracy should compare the car against factory literature, period photographs, and marque-club guidance to determine what is most appropriate for the specific chassis.

Correct tire fitment can influence both presentation and judging on a Citroen SM because tire size, stance, and sidewall treatment strongly affect how the car reads visually. A 1972 Citroen SM wearing 205R15 instead of 195R15, or a later car wearing a dramatic whitewall treatment, may look noticeably different from a more factory-oriented presentation.

That does not mean every owner needs the same result. A touring or personalized Citroen SM may prioritize drivability or visual style, while a judged restoration should follow year-correct size and era-appropriate appearance as closely as possible, with marque clubs and period reference material serving as the best guide for authenticity standards.

The listed Citroen SM options in 205R15 include blackwall and wide whitewall sidewall styles. For a restoration-minded car, blackwall is generally the more restrained and historically natural look for a sophisticated early-1970s European grand touring coupe, while the wide whitewall option creates a more customized appearance. Both are available, but they communicate different restoration priorities.

Owners restoring a Citroen SM to a factory-like visual standard should usually begin by comparing the car with period photographs and original market literature. If the goal is a personalized show presentation rather than strict authenticity, the wide whitewall option may still be appealing, but it should be chosen as a stylistic decision rather than assumed to be universal.

Properly sized, properly installed radial tires in the listed Citroen SM sizes can be suitable for public-road use when the rest of the car is mechanically sound. The available products for 205R15 are modern radial constructions rather than period-style bias-ply designs, which aligns well with the grand touring character of the Citroen SM. Safety still depends on condition, inflation, suspension health, and brake performance, not tire size alone.

A Citroen SM should be treated as a specialized collector car rather than as a modern daily driver. Before regular road use, make sure the tires are age-appropriate, free of visible defects, and fitted to sound 15-inch wheels, then confirm that the car’s steering, hydraulic systems, and alignment are in proper order.

Before driving a Citroen SM, check tire pressure, sidewall condition, tread condition, valve stems, and any signs of flat-spotting from storage. Verify that the car is wearing the correct year-specific tire size, with 195R15 for 1972 or 205R15 for 1973 and 1974, and make sure the tires are mounted on proper 15-inch rims. Any cracking, bulging, or persistent air loss should be addressed before road use.

That pre-drive inspection is especially important on a collector Citroen SM that spends long stretches parked between outings. A careful walkaround takes only a few minutes and can catch age-related tire issues early, which is worthwhile on a car whose ride and handling depend heavily on having the right tires in sound condition.

A Citroen SM should be driven at speeds appropriate to the actual tires fitted, their age, their condition, and the overall condition of the car. Even when the size is correct, an older collector tire should not be treated like a fresh modern high-performance tire simply because the vehicle itself was capable for its era. Tire condition matters as much as the sidewall code.

The wise approach is to build speed gradually and reserve sustained high-speed use for a Citroen SM that has been thoroughly inspected and fitted with sound, age-appropriate tires. If there is any doubt about the tire’s service life, age, or structural health, keep road use conservative until the assembly has been evaluated more closely.