1961 Triumph Tire Fitment Guide

1961 Triumph vehicles use four sizes across three model groups. Herald and Sedan models use either 145R13 radial or 520-13 bias-ply tires on 13-inch rims. TR3, TR4 & TR4A models use either 165R15 radial or 590-15 bias-ply tires on 15-inch rims. Rim width guidance appears on some products: 145R13 can fit 4.00 to 5.00-inch rims, 520-13 appears on 3.5 or 3.50 to 4.00-inch rims, 165R15 fits 4.50 to 6.00-inch rims, and 590-15 fits 4.00 to 4.50-inch rims where that specification is given.

That means year and make alone are not enough for a correct tire choice on a 1961 Triumph. Start by identifying whether your car is a Herald or Sedan in the small 13-inch group, or a TR3, TR4 or TR4A in the 15-inch sports-car group. Once the model is confirmed, you can narrow the choice to bias-ply for a more period-style appearance and feel, or radial for a more modern construction within the same wheel diameter family.

On a 1961 Triumph, 520-13 is a numeric bias-ply size. The 5.20 figure is the nominal section width in inches, written without a decimal in the code, and the 13 is the wheel diameter in inches. On 1961 Triumph applications, that size belongs to the Herald and Sedan rather than the TR sports cars. Products in 520-13 appear in blackwall and narrow whitewall versions, all within bias-ply construction.

For a buyer, 520-13 usually signals an earlier-style tire presentation than a metric radial. It suits owners who want the sidewall shape and period look associated with small British cars of the era, especially for restoration-minded use. Before committing to one, check your wheel width against the tire's approved range and decide whether blackwall or narrow whitewall better matches the way your particular Herald or Sedan is being restored or driven.

On a 1961 Triumph, 145R13 and 165R15 are metric radial sizes. The first number is the tire's nominal section width in millimeters, the R indicates radial construction, and the final number is the rim diameter in inches. In common vintage fitment use, these sizes are treated as 80-series radials. 145R13 belongs to Herald and Sedan models, while 165R15 belongs to TR3, TR4 & TR4A models.

Those codes matter because they separate not only two different wheel diameters, but also two very different Triumph platforms. A 13-inch radial for a Herald or Sedan is not interchangeable with a 15-inch radial for a TR. Once you have the correct size family, compare sidewall style, speed marking, and approved rim width for the specific product so the tire matches both the way the car looks and the way you intend to use it on the road.

For a 1961 Triumph Herald or Sedan, the choice between 145R13 and 520-13 is mainly a choice between radial and bias-ply construction, since both belong to the 13-inch wheel family for those models. The 145R13 options are blackwall radials from Michelin and Firestone, while 520-13 is a bias-ply size offered in blackwall and narrow whitewall versions. That makes the decision less about raw fitment and more about the kind of driving feel and visual presentation you want from the car.

Choose 520-13 when restoration accuracy and period appearance are the primary goal, especially if the car is being built with a distinctly early-1960s look. Choose 145R13 when you want a radial in the correct diameter family for regular road use. Either way, confirm your actual wheel width before ordering, because approved rim ranges differ by product and can be narrower on some bias-ply offerings than on the radial alternatives.

For a 1961 Triumph TR3, TR4 or TR4A, the decision between 165R15 and 590-15 follows the same radial-versus-bias-ply split, but in the 15-inch sports-car size family. The 165R15 radial is available in blackwall, narrow whitewall, and wide whitewall forms from several brands, while 590-15 remains a bias-ply choice from BFGoodrich and Avon in blackwall or wide whitewall form. Both sizes keep the car on a 15-inch rim, but they present very different period cues and construction types.

A 590-15 is the natural direction for a restoration that aims to preserve traditional TR stance and sidewall profile. A 165R15 is the better path for owners who want a 15-inch radial fitment on a regularly driven TR without moving outside the established size family for these cars. Wheel width still matters, so compare your rim against the approved range of the exact tire, especially when mixing original steel wheels with modern reproduction radials.

1961 Triumph tires cover a broad sidewall range depending on size. The 145R13 radial options are blackwall only, while 520-13 bias-ply options include blackwall and narrow whitewall versions. In the 15-inch TR sizes, 165R15 radials are available in blackwall, narrow whitewall, and wide whitewall styles, and 590-15 bias-ply tires come in blackwall or wide whitewall. That gives owners very different visual choices even within the same wheel diameter.

For most British sporting and saloon applications of this era, blackwall tends to be the safest visual choice when originality is the goal, especially on cars restored to a more factory-like appearance. Whitewall widths can still make sense for a personalized period look, export-market flavor, or a car built to owner taste rather than strict concours standards. If appearance is especially important, compare the sidewall treatment to period photos of your exact model and market version before choosing.

Rim width requirements for 1961 Triumph tires depend on the size. 145R13 radial products fit 4.00 to 5.00-inch rims, while 520-13 bias-ply products appear with 3.5-inch or 3.50 to 4.00-inch wheel guidance. In the TR range, 165R15 radial products fit 4.50 to 6.00-inch rims, and 590-15 bias-ply products fit 4.00 to 4.50-inch rims where rim width guidance is supplied. Those ranges show that two sizes sharing the same rim diameter do not necessarily share the same ideal wheel width.

That is especially important on vintage Triumphs, where original wheels, replacement wheels, and restored wheels may not all measure the same across the bead seats. Measure the wheel you actually have rather than assuming it matches a factory brochure or another owner's car. If your wheel lands near the edge of an approved range, it is worth checking the exact tire's recommendation before moving ahead, particularly when changing from bias-ply to radial construction.

Within each 1961 Triumph model group, the radial and bias-ply choices share the same rim diameter. Herald and Sedan models stay within 13-inch sizes whether you choose 145R13 or 520-13, and TR3, TR4 & TR4A stay within 15-inch sizes whether you choose 165R15 or 590-15. That means the original wheel diameter is compatible across the two size choices for a given model group. Rim width compatibility, however, still depends on the individual tire's approved range.

In practice, many owners move between the period-style bias-ply and a same-diameter radial without changing the wheel diameter at all. The key is to verify the actual wheel width and condition before mounting anything, because an original wheel that suits a narrower bias-ply perfectly may sit at the edge of the recommended range for a radial. This is one of the most important checks to make before any restoration or driver-oriented tire change on a 1961 Triumph.

A 1961 Triumph stores best in a cool, dry, dark space away from direct sunlight, electric motors, welders, battery chargers, and other ozone-producing equipment. Keep the tires clean, maintain proper inflation, and avoid long-term contact with standing moisture or oil-contaminated floors. Bias-ply tires such as 520-13 and 590-15 are generally more prone to temporary flat-spotting during extended static storage than radial sizes like 145R13 and 165R15, so periodic movement is especially useful when the car sits for long stretches.

If the car will sit for months, roll it occasionally or support it in a way that reduces prolonged loading on one patch of tread. Collectors who use tire cradles or stands still need to keep some air in the tires and inspect for sidewall aging when the car comes back into service. Good storage habits matter just as much on a lightly driven British collector car as they do on a frequently used one, because age and environment often matter more than mileage.

Tires on a 1961 Triumph should be judged more by age and condition than by miles traveled. A collector-car tire often deserves close evaluation once it reaches about five to seven years of service, and replacement should become a serious consideration as it approaches ten years, even if the tread still looks deep. The DOT date code on the tire sidewall is the best reference for age, and signs such as cracking, hardening, vibration, or persistent air loss can move that timeline forward.

Many vintage Triumphs spend more time parked than driven, which can make old tires look better than they really are. A low-mileage appearance is not the same as fresh rubber, especially if the car has lived through heat cycles, sunlight exposure, or long storage intervals. Build tire age into your maintenance plan the same way you would for hoses, belts, and brake hydraulics, and do not wait for visible tread wear alone to decide when replacement is due.

Tires on a 1961 Triumph should be checked before every drive and again before any longer outing or event. Look for sidewall cracking, tread separation, punctures, uneven wear, bulges, and slow pressure loss. Pay extra attention to valve stems and inflation retention on older collector cars, and be especially thorough with bias-ply applications such as 520-13 and 590-15 that may spend long periods parked between drives.

A quick walk-around before a short local drive can prevent a roadside problem that might otherwise look minor in the garage. Before a tour or highway trip, include the spare in the inspection, because a decades-old spare is often the weakest tire on the car. If the car has recently come out of storage, inspect again after the first few miles to catch any vibration, heat buildup, or pressure change that was not obvious when the tires were cold.

A 1961 Triumph Herald would have been associated with bias-ply construction in its original era, and the two established size families for Herald applications here are 520-13 bias-ply and 145R13 radial. For an originality-minded restoration, the 520-13 bias-ply is the period-authentic direction, while the 145R13 represents a radial alternative within the same 13-inch wheel diameter family. Original equipment branding could vary by market and delivery history, so size, construction, and sidewall treatment are usually the first authenticity checkpoints.

That matters most if the car is being judged, restored to factory-style presentation, or photographed with a strong emphasis on period correctness. Blackwall bias-ply tires are often the most conservative visual choice for a British compact of this era, while whitewall options can reflect owner taste or particular market styling rather than universal factory practice. If your Herald has an unusual body style or export history, a marque club or period sales literature is the best final authority before a concours restoration.

Correct tire fitment matters a great deal when showing a 1961 Triumph, especially at marque-focused or authenticity-driven events. Judges and knowledgeable enthusiasts will often notice whether the car wears the right size family, whether the construction is appropriate to the period, and whether the sidewall style suits the way the model would have appeared in its original context. A Herald or Sedan on a modern-looking radial may drive differently, but it can still look visibly less period-correct than the comparable bias-ply option.

For local shows and casual touring, owners often balance originality against personal driving preferences without concern. For stricter judging, keep the decision focused on the same factors that typically draw attention elsewhere on the car: size, construction type, and sidewall appearance. If the event has formal standards, ask the organizing club what they consider acceptable, because a tasteful radial conversion for road use may be treated very differently from a factory-style restoration entry.

For a 1961 Triumph Herald or Sedan in 145R13, the Michelin XAS-FF and Firestone F560 Radial differ in several concrete ways. Both are blackwall radials, but the Michelin carries a 145HR13 74H TL marking, giving it an H speed rating with a 130 mph ceiling, while the Firestone is marked simply 145R13. The Firestone also carries a published load figure of 825 pounds at 44 psi and fits 4.00 to 5.00-inch rims, while the Michelin shows a heavier 18-pound weight versus 12.7 pounds for the Firestone.

Those differences make this less about outward appearance and more about which specification profile better suits your priorities. An owner who wants to compare marked speed capability may pay special attention to the Michelin's H-rated marking, while another may focus on published rim width guidance and lighter weight in the Firestone. Both stay within the same radial 145R13 family, so the final decision should be made after confirming your wheel width and the way you intend to use the car.

1961 Triumph tires can be suitable for highway driving when the tire is in good condition, correctly inflated, and used within its rated capability. Among the sizes here, the Michelin 145R13 and Avon 590H15 carry H speed ratings, which correspond to a 130 mph ceiling. Other products in 145R13, 165R15, 520-13, and 590-15 may not carry the same speed marking, so the exact product matters. On a properly sorted 1961 Triumph, the car's brakes, suspension, alignment, and overall mechanical health are often just as important to safe road use as the tire itself.

For most normal U.S. highway use, the practical issue is not chasing top speed but making sure the tire matches the car, the wheel, and the condition of the rest of the chassis. A vintage British car that wanders, vibrates, or pulls under braking should be inspected before any long trip even if the tires are new. Confirm the specific speed marking on the tire you choose, keep pressures correct, and treat a reproduction collector tire as part of a complete roadworthiness check, not a cure-all by itself.

Inflation pressure on a 1961 Triumph depends on the exact tire size and product, and the tire's own marked load-and-pressure figure should never be copied across unrelated sizes. Published examples include 145R13 at 825 pounds and 44 psi on one Firestone radial, 520-13 at 770 pounds and 32 psi on one Firestone bias-ply and 1100 pounds at 60 psi on one Premium Sport version, 165R15 around 1168 to 1170 pounds at 35 to 36 psi on several radials, and 590-15 at 1050 pounds and 32 psi on BFGoodrich bias-ply examples.

Those figures are tire ratings, not automatic instructions to run every tire at its maximum pressure on the car. For everyday use, start with the factory recommendation from the owner's manual or service literature for your specific Triumph model, then compare that with the tire manufacturer's guidance for the exact reproduction or radial product you are using. Pressure tuning should also account for load, ride quality, and tread wear, but always stay within the tire's stated limits.

Before a longer drive in a 1961 Triumph, inspect each tire for cracking, cuts, punctures, bulges, uneven wear, and stable cold inflation pressure. Check the spare as carefully as the four road tires, because long-stored collector-car spares are often badly aged. If the car uses tube-type era bias-ply fitments, pay close attention to valve stem condition and any sign of air loss. A quick visual inspection is not enough if the car has sat for weeks or months.

The tire check should be part of a wider pre-trip routine that suits the age of the car: brakes, steering, fluids, wheel bearings, and cooling system all deserve attention before any extended outing. Triumphs are rewarding road cars, but they depend on regular mechanical vigilance in a way newer cars often do not. If the car has recently changed from one construction type to another, such as bias-ply to radial, it is smart to give it a short local test drive first and recheck pressure afterward.