1972 Honda Tire Fitment Guide

1972 Honda vehicles in this fitment group use two tire sizes, and both apply to the 1972 Honda 600: 145R10 and 5.20-10. Both sizes fit 10-inch wheels, so the basic rim diameter stays the same even though the sizing systems and construction types differ. The 145R10 is a radial metric-style size, while 5.20-10 is a traditional numeric bias-ply size.

That means the first thing to settle is not which Honda model you have, since only the 600 is covered here, but which tire character matches your goals. A radial usually appeals to owners who plan to drive the car regularly, while a bias-ply usually appeals to owners chasing a more period-authentic presentation. Wheel width should still be confirmed against the actual wheel before making the final choice.

On a 1972 Honda, 145R10 identifies a radial tire with a nominal section width of 145 millimeters and a 10-inch rim diameter. The R indicates radial construction. In this older euro-metric style, the aspect ratio is not written into the size code, but it is conventionally treated as an 80-series profile unless a different ratio is expressly shown.

That matters because 145R10 reads very differently from older inch-based sizes, even though it serves the same small-wheel Honda 600 application. If you are matching what is already on the car, check the full sidewall marking instead of relying on memory alone. A radial in this size also gives you access to several brand choices in blackwall form, including one example with an S speed rating.

On a 1972 Honda, 5.20-10 is a numeric bias-ply size. The 5.20 refers to the nominal section width in inches, and the 10 refers to the wheel diameter in inches. Unlike a radial metric code, it does not use millimeters or an R designator, and its appearance is immediately more traditional for an early-1970s small car.

That makes 5.20-10 especially relevant for owners restoring a Honda 600 to a more period-looking presentation. It should not be treated as interchangeable with any random 10-inch tire simply because the rim diameter matches. Confirm the exact size on the car, then decide whether preserving the original-style bias-ply character matters more to your project than moving to a radial construction.

For a 1972 Honda 600, the choice between 145R10 and 5.20-10 is mainly a choice between radial and bias-ply construction. Both fit 10-inch wheels, but they deliver a different ownership experience. The 145R10 is the radial option and is generally the better fit for owners who expect more regular road use, while the 5.20-10 bias-ply size aligns more naturally with period presentation and restoration-focused goals.

The smartest way to decide is to start with how the car will be used. A show-oriented Honda 600 often benefits visually from the traditional bias-ply route, while a car driven more often may justify the radial path. Keep the comparison focused on use case rather than assuming one size is universally correct, and confirm the wheel itself before changing from one construction type to the other.

1972 Honda 145R10 tires are available in blackwall form across the current radial choices for the Honda 600. That sidewall treatment suits the compact, economy-car character of the model and keeps the appearance appropriately understated. The sidewall emphasis here is less about decorative styling and more about matching the car's simple, functional original spirit.

For most Honda 600 owners, blackwall remains the most natural visual choice whether the goal is authenticity or a clean driver-quality presentation. If appearance matters as much as fitment, compare the sidewall look already on the car with the style you want to preserve after replacement. That extra step helps avoid ending up with the right size but the wrong visual tone for the finished car.

Four brands cover 1972 Honda 600 fitment in 145R10 radial form: Firestone, Kings, Camac, and Dunlop. Each of those options uses blackwall styling, and the Dunlop example carries an S speed rating with a 112 mph ceiling. That gives Honda 600 owners a useful mix of recognizable historic tire names and niche small-car coverage in the radial size.

Brand choice should come after size and construction choice, not before it. If you already know you want a radial 145R10, then brand, casing character, and any marked speed rating become the next points to compare. If your goal is a bias-ply restoration look instead, settle the 5.20-10 decision first and treat the brand discussion as secondary to preserving the right overall type of tire.

Tube fitment should be confirmed by the specific tire's sidewall marking and by the wheel itself on a 1972 Honda 600. The 145R10 radial options here do not carry a tube-type marker in the size markings, but that does not automatically settle whether a particular wheel condition or restoration setup calls for a tube. The final answer depends on the exact tire construction chosen and whether the wheel is suitable for tubeless service.

Older 10-inch wheels deserve a close inspection before a tire is mounted, especially on a low-production collector car like the Honda 600. Check for corrosion, pitting at the bead seat, previous repairs, and valve-stem condition before deciding on the final setup. If you are moving from a long-standing bias-ply arrangement to a radial, or from an older tube setup to a tubeless one, that is the right moment to have the wheel evaluated carefully.

The original-style 1972 Honda 600 wheels can often be used with both 145R10 and 5.20-10 because both sizes are built for a 10-inch rim diameter. That shared diameter is the key point of compatibility between the two fitment paths. The fact that one is a radial and the other is a bias-ply does not change the basic need for a 10-inch wheel.

Rim diameter alone is not the whole story, so wheel width and condition still need to be confirmed before switching sizes or constructions. A wheel that physically accepts one tire may not be the ideal match for every version of the other. If your Honda 600 still has its original wheels, a quick measurement and inspection before mounting new tires is a much better approach than assuming every 10-inch wheel behaves the same.

A 1972 Honda should be stored in a cool, dry, dark space away from direct sunlight, electric motors, furnaces, welders, and other ozone-producing equipment that can accelerate rubber aging. Keep the tires clean, maintain proper inflation, and move the car periodically so one section of the tread is not carrying the load for months at a time. Bias-ply tires are generally more prone to temporary flat-spotting during long static storage than radials.

If the Honda 600 will sit for an extended period, rolling it occasionally or using stands to reduce static load can help preserve the tire shape and sidewall condition. Storage habits matter just as much as mileage on a lightly used collector car. Good storage also protects the spare, which is easy to forget until the first roadside emergency or the first long drive after a seasonal layup.

On a 1972 Honda, tire life is usually governed more by age than by mileage. A collector-car tire should be evaluated closely once it reaches about five to seven years of age, and replacement becomes a serious consideration as it approaches roughly ten years, even if the tread still looks healthy. The DOT date code on the sidewall is the starting point for that timeline.

That age-based rule is especially important on a Honda 600 because many examples are driven sparingly and can appear mechanically sound while the rubber quietly hardens. Sidewall cracking, pressure loss, and a change in ride feel are all warning signs that deserve attention before the next outing. Keeping a maintenance log with installation dates helps prevent an old tire from staying in service simply because it still looks clean.

Tires on a 1972 Honda should be inspected before every drive and again before any extended outing. Check inflation, tread wear, cuts, bulges, weather checking, and any sign that the car has been sitting on a low tire. Because a Honda 600 is small and light, it can still feel drivable on aging tires that deserve replacement, so visual and pressure checks should be routine rather than occasional.

A longer trip calls for a more thorough inspection, including the spare and valve stems. If the car uses a tube-type setup, the stems and any signs of chafing or air loss deserve extra attention. Frequent inspection is one of the simplest ways to protect an older car from preventable roadside problems, especially when the vehicle's normal use pattern includes long periods of storage between short seasonal drives.

A 1972 Honda 600 would have been associated with small 10-inch tires, and bias-ply construction remained the traditional original-style fitment language for many economy cars of the era even as radials were becoming more common. Within this fitment range, 5.20-10 represents that more period-authentic bias-ply direction, while 145R10 reflects the radial alternative that many owners consider for later driving use. Original-equipment branding should be confirmed through marque-specific references before a judged restoration.

That distinction matters because originality is usually judged by more than diameter alone. If your Honda 600 is being restored for factory-style presentation, start by confirming whether the car's market, build period, and restoration goal call for a bias-ply look or allow for a radial interpretation. Honda clubs, original sales literature, and model specialists are the best next step when you want to narrow the fitment from broadly correct to event-level accurate.

Correct tire fitment absolutely matters when showing a 1972 Honda, especially on a car as visually distinctive and size-sensitive as the Honda 600. Judges and knowledgeable enthusiasts often notice whether the tire size, construction type, and sidewall presentation suit the period of the car. A radial can look out of place in a strict originality context if the class expects a bias-ply appearance, even when the wheel diameter is correct.

That does not mean every show applies the same standard, so the right approach depends on whether your Honda 600 is headed for local display, marque judging, or a concours field. Clarify the event's expectations before selecting between 145R10 and 5.20-10. Getting that choice right helps the whole stance and visual character of the car read correctly, which is especially important on a very small car where tire proportions stand out immediately.

For a 1972 Honda 600 in 145R10, Firestone and Dunlop both offer radial blackwall options on a 10-inch rim, but they are not identical in detail. The Firestone option appears as the F560 Radial, while the Dunlop option appears as the SP Sport Aquajet and carries an S speed rating, which corresponds to a 112 mph ceiling. Their published weights also differ, with each tire sitting in the light small-car range rather than the heavier construction seen on larger vintage applications.

That kind of difference matters most to buyers comparing period flavor, marked speed category, and brand character within the same size rather than trying to solve a fitment problem. Both remain part of the 145R10 radial path for the Honda 600, so the real comparison is within one construction choice, not between incompatible tire families. If you are narrowing the final pick, sidewall appearance and how closely you want to match the car's era are sensible tiebreakers.

1972 Honda tires can be suitable for highway driving when they are in good condition, correctly inflated, and used within their construction type and marked speed capability. In the 145R10 radial range, one option carries an S speed rating, which corresponds to a 112 mph ceiling. That figure is far beyond the pace a healthy Honda 600 would normally be asked to sustain, so the practical limits on real roads are often the car's age, braking, suspension, and overall mechanical condition rather than the tire alone.

Safety comes from treating the tire as one part of the whole system. Before highway use, confirm the tire age, sidewall condition, inflation, wheel condition, and balance, then consider how the car is actually used. A well-sorted Honda 600 on fresh tires is a very different proposition from a long-stored car wearing old rubber, even if both still carry the same size marking on the sidewall.

Inflation pressure on a 1972 Honda should be tied to the exact tire size and the vehicle's factory recommendation rather than guessed from a modern compact-car rule of thumb. Within the 145R10 group, one radial carries a 694-pound load figure at 30 psi, which is a tire rating reference rather than a blanket instruction for every product or every setup. Pressure should not be transferred casually from 145R10 to 5.20-10 or from one brand to another.

The best practice is to start with the Honda owner's manual or period service literature, then compare that guidance with the tire maker's sidewall and specification standards for the exact tire you are using. That approach keeps the car within an appropriate pressure range while respecting the differences between old and new constructions. It also helps avoid overinflating a light car simply because a tire's maximum-rated pressure is easy to find.

Before a longer drive in a 1972 Honda, inspect each tire for cracking, cuts, bulges, punctures, uneven wear, and any sign of age-related hardening. Verify cold inflation pressure, look closely at the valve stems, and make sure the spare is usable rather than simply present. On a small vintage car like the Honda 600, the tires deserve the same attention as the brakes, fluids, belts, and charging system before a day trip or event drive.

A short pre-drive check is often enough to catch the problems that strand collector cars: a tire that slowly leaks, a spare that has aged out, or a sidewall that looked acceptable until it was viewed in direct light. If the car has been parked for a long period, give the tires a little road time at moderate speed before committing to a longer highway run. That helps reveal vibration, flat-spotting, or pressure issues early.