Bertone X-1/9 Tires

Bertone X-1/9 fitment in the years covered here uses two tire sizes. The 1984, 1985, and 1986 Bertone X-1/9 use 165/70R13, while the 1987, 1988, and 1989 Bertone X-1/9 use 185/60R13. Both sizes are radial tires built for 13-inch rims, so the change is in width and profile rather than wheel diameter.

That year split matters because a later low-profile size should not be assumed correct for an earlier car, and an early taller-profile size should not be assumed correct for a later one. Start with the model year, then verify the tire placard, wheel size, and any restoration history so the car is matched to the right period of Bertone X-1/9 production.

On a Bertone X-1/9, 165/70R13 is a metric radial size. The 165 is the nominal section width in millimeters, 70 is the aspect ratio, R identifies radial construction, and 13 is the rim diameter in inches. That size applies to 1984 through 1986 Bertone X-1/9 models in the years covered here.

Understanding the code helps prevent a common mistake with later replacement choices. A 165/70R13 has a narrower section and taller sidewall than the later Bertone X-1/9 size, so owners of early cars should verify that any wheel or suspension changes have not altered the original intended fitment before changing sizes.

Bertone X-1/9 models in this production range use 13-inch rims throughout 1984 to 1989. The tire size changed in 1987 from 165/70R13 to 185/60R13, but the wheel diameter did not change. The available listed product for the later size also confirms a 13-inch rim diameter.

That makes the wheel diameter question simpler than the tire size question. You still need to confirm the actual wheels on the car, especially if the Bertone X-1/9 has been modified over the years, but the year-based fitment split here is driven by tire dimensions rather than a move to a different diameter wheel.

A 1987 Bertone X-1/9 falls into the later production group and uses 185/60R13. That size continues through 1988 and 1989, while 1984 through 1986 cars use 165/70R13. The covered fitment change happens at the 1987 model year, with both early and late groups remaining on 13-inch rims.

For a 1987 Bertone X-1/9, the smartest next step is to confirm the year from the VIN tag or registration and then inspect the wheels and any prior modifications. Cars that have passed through multiple owners sometimes wear non-original wheel and tire combinations, so the model year should be matched against the car’s actual current hardware before choosing a replacement tire.

The available Bertone X-1/9 product shown here uses a blackwall sidewall style. No additional sidewall styles appear among the listed products for this make and model group. The currently listed offering is the Michelin Pilot Exalto PE2 in 185/60R13.

Blackwall styling suits the Bertone X-1/9’s later sports-car character and is visually appropriate for many 1980s European applications. If appearance matters as much as fitment, compare the sidewall look on the car now with period photos, wheel finish, and the overall restoration direction so the tire does not feel out of step with the car’s presentation.

The listed Bertone X-1/9 product coverage includes Michelin. The available product is the Michelin Pilot Exalto PE2 in 185/60R13, which applies to 1987 through 1989 Bertone X-1/9 models. No additional brands appear among the current products for this model group.

Brand availability matters most after the correct size has been confirmed. If you own an early Bertone X-1/9 that uses 165/70R13, focus first on verifying the exact year and present wheel setup, because the brand question only becomes useful once the car has been matched to the correct size category.

A Bertone X-1/9 should be stored on a clean, dry surface away from direct sunlight, electric motors, welders, and ozone sources that can age rubber prematurely. Keep the tires properly inflated, avoid long periods with the car carrying unnecessary weight, and roll the car occasionally so the same part of each tire is not constantly loaded.

That approach helps preserve both the rubber and the ride quality on a light mid-engine car like the Bertone X-1/9. If the car will sit for an extended period, a careful owner may also use flat-stopper pads or suitable stands as part of a broader storage plan, provided the chassis is supported correctly and safely.

Tires on a Bertone X-1/9 should be inspected before every drive and more thoroughly at regular intervals during the driving season. Look for cracking, bulges, punctures, uneven wear, and pressure loss, and check that the tread is wearing evenly across the tire. Collector cars often accumulate little mileage, so age and storage effects matter as much as tread depth.

Frequent inspection is especially important on a Bertone X-1/9 because steering feel and handling balance can change noticeably when pressures drift or the rubber begins to harden. A quick check in the garage can prevent a pleasant back-road drive from turning into a vibration, tracking, or stability problem caused by an aging tire.

A Bertone X-1/9 tire should be replaced when it shows age cracking, hardening, sidewall damage, irregular wear, puncture damage beyond safe repair, or any sign of structural deterioration even if the tread still looks deep. Low-mileage collector cars often age out their tires before they wear them out. Calendar age, storage history, and condition matter more than appearance alone.

That rule is particularly important for a Bertone X-1/9 because a small, responsive sports car depends on predictable tire behavior. If the car has sat for long periods, or if the tires’ age is uncertain, have them evaluated by a knowledgeable tire professional and treat replacement as preventive maintenance rather than waiting for visible tread wear.

The fitment range covered here shows two period groupings for the Bertone X-1/9: 165/70R13 for 1984 through 1986 and 185/60R13 for 1987 through 1989. The listed available product coverage includes a Michelin radial for the later size. That establishes the year-based size progression, but original factory brand and exact original tire specification can vary by market and surviving vehicle history.

For a restoration, the best path is to pair the correct year-range size with the car’s surviving labels, manuals, and marque references. A Bertone X-1/9 restored for authenticity benefits from having the right dimensions first, because overall stance and sidewall proportion are often more visually important than chasing a brand name without confirming the proper size.

Correct tire fitment can affect both the presentation and the perceived authenticity of a Bertone X-1/9. Judges, marque enthusiasts, and experienced buyers often notice whether the tire size suits the production year, whether the sidewall style looks appropriate, and whether the overall stance matches the car’s era. A visibly incorrect size can distract from otherwise careful restoration work.

That does not always mean a road-driven Bertone X-1/9 must be restored to concours standards, but the closer the car is to stock appearance, the more important correct size selection becomes. Owners aiming at shows or resale should compare the tire choice with marque club guidance and period imagery so the finished car looks coherent and properly sorted.

The currently listed Bertone X-1/9 product uses a blackwall sidewall, which is a natural visual fit for a late-classic 1980s sports car. No whitewall or specialty sidewall style appears among the listed products for this model group. For the years covered here, blackwall presentation aligns well with the X-1/9’s crisp, modern-for-its-time styling.

Owners restoring a Bertone X-1/9 for a clean period look should think about sidewall style together with wheel finish, ride height, and the correct year-based size. Even when a tire physically fits, an overly modern or visually mismatched sidewall can change the character of the car more than many restorers expect.

A properly sized, properly inflated, undamaged radial tire in the correct Bertone X-1/9 fitment can be suitable for normal public-road use. The covered Bertone X-1/9 sizes are modern metric radials on 13-inch rims, and the listed available product is a radial tire intended for later 1987-1989 cars. Safety depends on condition, age, inflation, alignment, and matching the tire to the correct year group.

Before regular road use, make sure the Bertone X-1/9 has no old, hardened, or cracked tires and that the car tracks correctly without vibration or pull. A lightweight mid-engine car can react quickly to tire problems, so road safety comes from correct size selection plus careful inspection rather than from the size code alone.

Before driving a Bertone X-1/9, check tire pressure, visible condition, tread wear, wheel security, and whether all four tires are the correct size for the car’s production year. Inspect for sidewall cracking, punctures, and signs of long-term storage damage. If the car is newly acquired, also verify that the wheels are actually 13-inch wheels and not a later modification.

Those checks matter because the Bertone X-1/9’s compact chassis and direct steering will quickly reveal a tire problem, but often only after the car is already in motion. A short garage inspection and a cautious first few miles can uncover age-related issues before they turn into a roadside problem or compromise the car’s handling balance.

A Bertone X-1/9 should be driven at speeds appropriate to the tire’s actual condition, inflation, and rating, not simply to the car’s capabilities. The listed later-size product is a modern radial, but no collector car should be driven aggressively on aged, damaged, or questionable tires. Even when tread looks acceptable, age and storage history can sharply reduce real-world confidence.

For practical road use, the sensible approach is to keep the Bertone X-1/9 within moderate speeds until the tires, suspension, and alignment have all been checked and proven stable. If there is any uncertainty about age, vibration, or hardening of the rubber, reduce speed accordingly and correct the issue before asking the car to perform like a fresh sports car.