1958 BMW 502 Tires

The 1958 BMW 502 uses two primary tire sizes: 640-15 in a bias-ply construction and 185R15 in a radial construction. Both are 15-inch fitments, so the choice is centered more on construction style and wheel compatibility than on switching to a different rim diameter.

That means the first step is confirming how the car is currently set up. A restoration-oriented BMW 502 may stay with 640-15 for a more traditional profile, while a road-driven car may already use 185R15 radials. Wheel width, suspension condition, and fender clearance should all be verified before changing from one size format or construction type to the other.

The 1958 BMW 502 uses a 15-inch rim with both of its primary tire sizes. The 640-15 bias-ply and the 185R15 radial are both built around that same rim diameter, which simplifies the diameter question but does not remove the need to verify the wheel itself.

Rim diameter is only one part of the fitment picture. A 15-inch wheel can still vary in width, and that becomes especially important when comparing bias-ply and radial options. Measuring the actual wheel on the car is worthwhile, particularly if the BMW 502 has been restored, re-wheeled, or converted for more frequent road use over the years.

The 1958 BMW 502 Base uses the same two fitment paths covered on this page: 640-15 in bias-ply form and 185R15 in radial form. There is not a separate Base-only size within this fitment range, so the main distinction is construction rather than trim-specific sizing.

That keeps the decision focused on how the car is being presented and driven. A Base model restored around a traditional mid-century appearance may lean toward the 640-15 bias-ply, while a car set up for regular touring may be matched to the 185R15 radial. Wheel width and present-day chassis setup should still be checked before settling on either route.

640-15 is a bias-ply tire size for the 1958 BMW 502. It uses the vintage numeric sizing system common to the period, and it is offered in bias-ply form with blackwall, narrow whitewall, and wide whitewall sidewall treatments depending on the specific tire chosen.

That matters because a bias-ply tire shapes both the car’s appearance and its setup requirements differently than a radial does. Owners comparing 640-15 to a radial alternative should make sure the wheel width, tire dimensions, and clearance are all suitable for the intended tire. The decision often comes down to preserving a traditional presentation versus choosing a radial-format setup.

Radial equivalents for 640-15 include 175R15, P175/75R15, and P185/70R15. The 175R15 is the 80-series metric radial equivalent, P175/75R15 is the 75-series P-metric alternative, and P185/70R15 is the 70-series P-metric alternative for buyers comparing different radial sizing conventions.

These sizes are useful comparison points rather than automatic replacements. A recommended rim-width range of 5 to 6 inches is associated with those radial equivalents, so the actual wheel on the BMW 502 should be measured before making a change. Tire dimensions, steering clearance, and how the car sits within the fenders are all worth checking during any conversion.

Start by confirming the wheel diameter and actual wheel width on the car, then compare the intended radial size to the BMW 502’s present bias-ply setup. For a car moving away from 640-15, the radial-equivalent choices include 175R15, P175/75R15, and P185/70R15, all of which should be evaluated against the wheel and chassis.

A careful conversion also includes checking front and rear clearance, steering travel, suspension condition, and any prior modifications. The car may no longer be on its original wheels or ride height, especially after restoration work. Looking at the car as it actually sits today is more useful than assuming every 15-inch wheel or every radial equivalent will behave the same way.

Begin with the two primary fitment paths: 640-15 if the car is staying with a traditional bias-ply setup, or 185R15 if it is using a radial. From there, the meaningful choices are construction type, wheel-width compatibility, sidewall appearance, and whether the BMW 502 is being restored for visual authenticity or prepared for more regular road use.

It also helps to compare the character of the available products rather than focusing only on size. Some tires emphasize a whitewall presentation, some keep a plain blackwall look, and some radial offerings add details like redlines. A carefully chosen tire should suit the way the car is used, not just the wheel diameter stamped into the rim.

The 1958 BMW 502 has several sidewall styles available across its tire options. Blackwall appears in both 185R15 radial and 640-15 bias-ply choices, redline is offered in 185R15, narrow whitewall appears in both constructions, and wide whitewall is available in 640-15 bias-ply form.

That variety lets the tire play a major role in the car’s final presentation. A wide whitewall can reinforce a formal late-1950s look, while a blackwall often feels more restrained and technical. Redline gives the radial size a more customized visual direction. The best choice depends on whether the BMW 502 is being finished as a traditional restoration or a personalized driver.

Tires for the 1958 BMW 502 are available from Coker Classic, Michelin, Avon, Universal Vintage Tire, BFGoodrich, Firestone, and Excelsior. Those brands are spread across the car’s two main size paths, with radial offerings centered on 185R15 and bias-ply offerings centered on 640-15.

Brand choice should be treated as part of the overall selection process rather than the only decision. It makes sense to compare the tire series, sidewall style, construction, and wheel-width suitability within each brand’s offering. For this BMW, the most useful question is not simply who makes the tire, but which available tire best suits the car’s intended appearance and road use.

For a period-style 1958 BMW 502, the 640-15 bias-ply is the most traditional starting point because it preserves the vintage numeric size format and offers sidewall treatments that suit a formal late-1950s sedan. Blackwall, narrow whitewall, and wide whitewall versions are all available within that bias-ply size.

The final choice depends on how strictly the car is being restored and what visual effect is desired. A whitewall treatment can change the BMW’s character noticeably, while a blackwall keeps the presentation more restrained. When exact originality matters, marque references and period photos are worth consulting so the selected sidewall style matches the car’s intended restoration direction.

Tire construction changes the visual language of a restored 1958 BMW 502 as much as it changes the driving setup. A 640-15 bias-ply gives the car a more traditional mid-century stance and sidewall profile, while an 185R15 radial usually presents a more modern tire format even when offered in period-style sidewall treatments.

That difference matters on a car with formal proportions and strong wheel-arch presence. Owners aiming for a restoration-oriented look often start by deciding whether the car should read as authentically mid-century at a glance or as a vintage sedan prepared for more contemporary road use. Sidewall choice can refine the result, but construction sets the tone first.

Yes, modifications can affect tire fitment on a 1958 BMW 502 even when the tire size appears correct on paper. Changes to wheel width, wheel offset, ride height, suspension parts, or brake components can alter how a 640-15 or 185R15 sits in the wheel opening and how much clearance remains during steering and suspension travel.

That is why the actual car should always be checked rather than relying only on catalog sizing. A restored BMW 502 may have replacement wheels or chassis updates that shift the fitment picture. Looking at wheel-to-fender space, steering clearance, and the tire’s relationship to suspension hardware can prevent surprises once the car is back on the road.

Before driving a 1958 BMW 502 on new tires, inspect the wheels for correct diameter and condition, confirm that the beads seat properly, and check that inflation matches the tire being used. It is also wise to look over steering and suspension components so the new tires are not being asked to work around worn or loose hardware.

A short clearance check is just as important as the tire installation itself. Turn the steering from lock to lock, look for contact near fenders and suspension parts, and recheck pressure after the first few drives. On a collector sedan that may have sat for long periods, catching small issues early helps protect both the tires and the driving experience.

Tires on a collector 1958 BMW 502 should be kept properly inflated, inspected regularly for cracking, bulges, cuts, and uneven wear, and monitored for slow air loss between drives. Even when tread looks usable, a low-mileage collector car can still have tire condition issues that come from age, storage, or long periods of inactivity.

Storage habits matter almost as much as mileage on a vintage BMW. Keeping the car away from prolonged sunlight, excess heat, moisture, and ozone sources helps protect the sidewalls over time. It also helps to move the car periodically or use appropriate storage practices so the tires are not left carrying the same load in the same position for months.