BMW 733i Tires

The BMW 733i uses two tire sizes across 1978 through 1984: 205/70R14 and 220/55R390. The 205/70R14 size mounts on 14-inch wheels, while the 220/55R390 size mounts on 390mm Michelin TRX wheels. Both sizes appear across the full production span, so year alone does not separate them.

The practical step is to inspect the car’s actual wheels and the size currently fitted before choosing a replacement. A BMW 733i with 14-inch wheels needs the inch-based tire, and a BMW 733i with TRX wheels needs the metric TRX tire. If the car has changed hands or been restored, wheel swaps are common enough that the wheel itself matters more than assumptions about original configuration.

On a BMW 733i, 220/55R390 is a metric radial size used with Michelin TRX wheels. The 220 indicates a 220mm section width, 55 is the aspect ratio, R identifies radial construction, and 390 is the rim diameter in millimeters rather than inches. That last number is the key distinction, because it does not correspond to a conventional 14-inch wheel.

This matters because a BMW 733i wearing TRX wheels must stay with the correct metric-size tire unless the car has been converted to a different wheel package. The easiest mistake is assuming a metric TRX tire is just another version of a common modern radial size. Checking the wheel markings and the existing tire sidewall will prevent an expensive mismatch.

The BMW 733i uses either a 14-inch rim diameter or a 390mm rim diameter. The 14-inch fitment corresponds to 205/70R14 tires, while the 390mm fitment corresponds to 220/55R390 Michelin TRX tires. Both wheel diameters appear from 1978 through 1984.

A buyer should treat wheel diameter as the first fitment checkpoint on a BMW 733i. The two systems are not close substitutes, and a tire built for one will not mount correctly on the other. If the car’s history is unclear, remove the hubcap if necessary and confirm the wheel stamping or match the current tire size exactly before moving on to sidewall style or brand preference.

A 1981 BMW 733i can use either 205/70R14 or 220/55R390, so the correct answer comes from the wheel on the car rather than the year alone. If the car has a conventional 14-inch wheel, the correct size is 205/70R14. If it has the metric Michelin TRX wheel system, the correct size is 220/55R390.

Start by reading the size molded into the tire sidewall and then confirm it against the wheel diameter. If the current tires are old, mismatched, or missing, measure carefully and compare the wheel markings before selecting a replacement. On a BMW 733i, this extra step is worth taking because the inch-based and TRX fitments serve the same years but are mechanically different wheel systems.

BMW 733i tires are available with several sidewall styles, including narrow whitewall, blackwall, redline, dual redline, and raised white letters. The 205/70R14 size has the widest variety, while the 220/55R390 TRX fitment is offered as a blackwall. All of these are radial tires, but the appearance changes the visual character of the car considerably.

For a more factory-like executive-sedan look, many owners prefer blackwall styling on a BMW 733i, especially on TRX-equipped cars. Whitewall, redline, or raised-white-letter treatments can push the car toward a more customized or period-personalized appearance. If the goal is a restoration with judging in mind, compare the chosen sidewall style against period photos, original paperwork, or marque-club references for your specific car.

BMW 733i tire options here come from Maxxis, BFGoodrich, and Michelin. The 205/70R14 size includes choices from all three brands, while the 220/55R390 TRX size is represented by Michelin. That gives inch-wheel cars more variety in both appearance and tire series.

Brand selection on a BMW 733i often comes down to how the car is used and how original you want it to look. A driver focused on preserving the TRX wheel system will be shopping within the Michelin metric fitment, while a car on 14-inch wheels has more freedom in sidewall styling and series choice. Once the wheel diameter is confirmed, brand becomes a secondary decision behind correct size.

BMW 733i tires here appear in several distinct series: Classic Whitewall MA-1, Radial T/A, Silvertown Radial, Michelin XWX, and Michelin TRX-B. All are radial tires, but they differ in intended appearance and fitment. Some emphasize period blackwall or whitewall styling for 14-inch wheels, while Michelin TRX-B is specifically built for the 390mm TRX system.

The useful way to sort these choices is by wheel type first and visual character second. A BMW 733i on conventional 14-inch wheels can lean toward understated touring style or more pronounced period custom cues, depending on the sidewall treatment. A BMW 733i on TRX wheels is a narrower path: preserving the original metric wheel concept means staying within the TRX-compatible series built for that rim diameter.

A BMW 733i should be stored on a clean, dry surface away from direct sunlight, ozone sources, and large temperature swings. Tire pressure should be maintained during storage, and the car should not be left for long periods with severely underinflated tires. If storage will be extended, moving the car periodically helps reduce flat spotting.

Owners who keep a BMW 733i for seasonal driving should also inspect the sidewalls before and after storage because appearance tires and specialty metric fitments can be expensive to replace. Keeping the car indoors, avoiding petroleum contamination, and preventing one spot of the tread from carrying the car’s full weight for months at a time will help preserve both ride quality and appearance.

Tires on a BMW 733i should be inspected before regular road use and at least several times during the driving season, even if the car covers low mileage. Look for sidewall cracking, tread separation, impact damage, punctures, uneven wear, and signs of long-term underinflation. On TRX-equipped cars, inspect the wheel and bead area carefully because the metric wheel system depends on the correct matched tire.

A collector BMW 733i often ages its tires out before it wears them out, so visual condition matters as much as tread depth. If the steering feel changes, the car develops vibration, or one tire loses pressure faster than the others, stop and investigate rather than driving through the symptom. Regular inspection is especially important on cars that spend more time parked than driven.

A BMW 733i tire should be replaced when age, cracking, hardening, impact damage, or structural concerns appear, even if the tread still looks usable. Collector cars commonly preserve tread because they see limited mileage, but rubber condition still deteriorates over time. Any tire that shows persistent air loss, deformation, or visible casing distress belongs on the replacement list immediately.

The practical rule for a BMW 733i is to judge the tire as a complete assembly, not by tread depth alone. Owners of TRX-equipped cars should be especially attentive because specialty metric fitments are often retained for originality and may stay on the car longer than they should. If there is any doubt about the age or structural condition of a mounted tire, a vintage-tire specialist inspection is worthwhile before road use.

BMW 733i fitments in this range include both 205/70R14 and 220/55R390, which shows that the model was associated with both conventional inch-based radial tires and the Michelin TRX metric system. Available series here include Michelin XWX and Michelin TRX-B along with other radial options in the 14-inch size. That means the correct original-type answer depends on the specific wheel package and configuration of the car.

A restoration-minded owner should match the tire choice to the wheel type currently on the BMW 733i and then compare it against original sales literature, window sticker information, or marque-club references. Cars preserved with TRX wheels generally make the strongest originality case with the matching metric tire system. Cars on 14-inch wheels have more than one plausible path, so the goal should be consistency with the car’s own history.

Correct tire fitment can affect both the presentation and the judged authenticity of a BMW 733i. Judges and knowledgeable buyers tend to notice whether the wheel system, tire size, and sidewall appearance suit the period and the specific configuration of the car. A TRX-equipped BMW 733i, in particular, stands out when it retains the proper metric wheel-and-tire relationship.

For market value, the impact depends on the audience. A driver-quality BMW 733i may prioritize usability, while a preservation or concours-oriented car benefits from tire choices that support its original character. If the car is being prepared for formal judging, compare the selected size and sidewall style with marque-club guidance and period photography so the tire decision supports the rest of the restoration.

BMW 733i tires here are offered in blackwall, narrow whitewall, redline, dual redline, and raised white letter forms, but the most restoration-oriented look for a late-1970s to mid-1980s executive BMW is usually conservative. Blackwall is the most natural visual match for a European luxury sedan of this era, and the TRX fitment is available as a blackwall. Whitewall and performance-style sidewall treatments are available mainly in the 14-inch fitment.

The right choice depends on whether the BMW 733i is being restored to factory-style presentation or to a period-personalized look. If authenticity is the goal, start with blackwall and compare against period photos of cars equipped like yours. If the car already wears non-original wheels or has been modified in period style, one of the alternate sidewall treatments may still be visually appropriate even if it is not the strictest restoration path.

These tires can be suitable for public-road use on a BMW 733i when the correct size is matched to the correct wheel, the tires are in sound condition, and the rest of the car is mechanically prepared for road service. All of the listed BMW 733i options are radial designs, but the essential safety point is still proper wheel-to-tire compatibility. A 14-inch tire on a TRX wheel, or the reverse, is not an acceptable combination.

Road safety also depends on age, inflation, alignment, brakes, and suspension condition. Before regular use, a BMW 733i should be evaluated as a complete system rather than judged by tread appearance alone. If the car has spent years parked, begin with a careful recommissioning inspection so the tire choice works in step with the chassis and steering the way BMW intended.

Before driving a BMW 733i, check tire pressure, sidewall condition, tread condition, wheel integrity, valve stems, and any signs of impact or age cracking. Confirm that all four tires match the wheel system in use, especially if the car has metric TRX wheels. Uneven wear or a pull at the steering wheel can also point to alignment or suspension issues that should be addressed before extended driving.

A short pre-drive walkaround is one of the best habits for a collector BMW 733i. Cars that sit for long periods can develop flat spotting, slow air loss, or weather checking without much warning. If anything looks questionable, correct it before the drive rather than hoping the car will sort itself out once underway.

A BMW 733i should be driven at speeds appropriate to the condition of the tires, wheels, suspension, and braking system rather than to the car’s theoretical performance. Even when a period-correct radial size is fitted, age and storage history matter as much as the name on the sidewall. The safe operating envelope shrinks quickly if the tires are old, hardened, or of uncertain service history.

For a regularly used BMW 733i on fresh, correctly fitted tires, normal road speeds may be reasonable when the rest of the car is sorted. For a recently awakened car, a low-mileage survivor, or one wearing older tires, start cautiously and build confidence only after inspection and road testing. The right speed is the one supported by the condition of the complete car, not just the tread depth.