1961 Fairthorpe Tire Fitment Guide

1961 Fairthorpe vehicles use six sizes across three model lines. The Electrina uses either 155R13 radial or 560-13 bias-ply on 13-inch rims. The Electron uses either 155R15 radial or 560-15 bias-ply on 15-inch rims. The Zeta uses either 185R15 radial or 6.50-15 bias-ply on 15-inch rims. Rim width guidance appears on several products: 155R13 generally spans 4.00 to 5.50 inches, 560-13 runs from 3.50 to 4.50 inches depending on tire, 155R15 spans 4.00 to 5.50 inches, 560-15 reaches 4.50 to 5.50 inches, and 185R15 spans roughly 4.5 to 6.50 inches.

The practical takeaway is that 1961 Fairthorpe fitment begins with model identification, not just year and make. Electrina owners need the 13-inch pair, while Electron and Zeta owners both use 15-inch wheels but not the same tire sizes. Once the model is confirmed, the next step is deciding whether a period-style bias-ply tire or a radial better fits the way the car will be restored, shown, and driven.

On a 1961 Fairthorpe, 560-15 is a numeric bias-ply size. The 5.60 figure is the nominal section width in inches, while the 15 identifies the wheel diameter in inches. That format belongs to the older bias-ply sizing system rather than the later metric radial system. On the Fairthorpe Electron, 560-15 is the bias-ply counterpart to 155R15 and mounts on a 15-inch wheel.

That matters because a 560-15 tire is chosen for more than just wheel diameter. It also carries the visual character and operating feel of a period bias-ply tire, especially when paired with narrow or wide whitewall styling. If your Electron is being restored with originality in mind, 560-15 is usually the first size to investigate. If the car is being driven more regularly, compare it directly with the 155R15 radial before making the final call.

No, 1961 Fairthorpe models do not share one universal tire size. The Electrina uses 13-inch sizes, specifically 155R13 or 560-13. The Electron uses 15-inch sizes, specifically 155R15 or 560-15. The Zeta also uses 15-inch wheels, but its sizes are larger at 185R15 or 6.50-15. Each model has its own radial-and-bias pairing rather than borrowing the same size across the full Fairthorpe line.

That means a buyer cannot safely choose tires for a 1961 Fairthorpe by year and make alone. The model name has to be established first, especially because Electron and Zeta both use 15-inch wheels but not the same tire widths. Once the model is confirmed, compare the radial and bias-ply option within that model rather than assuming any 15-inch Fairthorpe tire will suit every car in the range.

For a 1961 Fairthorpe, the radial-versus-bias choice depends on the model and the car's intended use. The Electrina pairs 155R13 with 560-13, the Electron pairs 155R15 with 560-15, and the Zeta pairs 185R15 with 6.50-15. The bias-ply sizes reflect the period construction style associated with early-1960s fitment, while the radial sizes bring later tire construction to the same model-specific wheel diameter. On the radial side, some sizes also carry higher modern speed markings such as T, H, or V depending on the exact tire.

Owners focused on a restoration presentation often start with the bias-ply option because construction and sidewall appearance can matter as much as raw dimensions. Owners planning more regular road use often prefer to evaluate the radial alternative for the same model. The key is to compare within the correct model pair rather than across the full Fairthorpe line. An Electrina should be choosing between its two 13-inch sizes, while Electron and Zeta owners should stay within their own 15-inch size pairings.

1961 Fairthorpe tires come in several sidewall styles depending on size. The 155R13 and 155R15 radial sizes are available in blackwall form. The 560-13 and 560-15 bias-ply sizes are available with narrow whitewall and wide whitewall styling. The 185R15 radial size offers the broadest cosmetic range, including blackwall, narrow whitewall, and redline. That gives Fairthorpe owners different visual directions even before getting into model-specific wheel diameter and construction.

For a 1961 British specialty sports car, blackwall is often the most understated and competition-minded appearance, while whitewalls or redlines can create a stronger period-custom or touring look depending on the owner's vision for the car. The important point is to keep the style choice anchored to the correct model size first. After that, sidewall treatment becomes a way to tune the finished look without changing the underlying fitment category.

Several brands cover 1961 Fairthorpe fitments, but they do so by size rather than across the whole range. 155R13 is available from Michelin and Dunlop. 560-13 comes from BFGoodrich and Firestone. 155R15 is covered by Firestone and Michelin. 560-15 is available from Firestone and US Royal. 185R15 is available from Coker Classic and Michelin. That mix gives each Fairthorpe model its own brand landscape once the correct size has been identified.

Brand choice should come after the size and construction decision, not before it. A buyer who starts with a preferred name may find that the brand changes once the model and sidewall style are narrowed down. That is especially true in the Fairthorpe range because the Electrina, Electron, and Zeta do not share one common fitment. The cleanest path is to identify the exact model, select the appropriate radial or bias-ply size, and then compare the brands available within that fitment.

Rim width requirements for 1961 Fairthorpe tires vary by size. The 155R13 radial works across 4.00 to 5.50-inch rims, while 560-13 bias-ply options span 3.50 to 4.50 inches depending on tire. The 155R15 radial works across 4.00 to 5.50-inch rims, and 560-15 bias-ply options run from 4.50 to 5.50 inches. The 185R15 radial size reaches from roughly 4.5 to 6.50 inches, depending on the tire selected.

Those ranges matter because two tires with the same rim diameter do not always share the same ideal wheel width. Before mounting anything on a 1961 Fairthorpe, compare the actual wheel width on the car against the exact tire you plan to use. That is especially important when switching between bias-ply and radial construction, or when choosing among different brands within the same size, because acceptable wheel-width windows can differ.

Inner-tube requirements for 1961 Fairthorpe tires depend on the exact size and tire chosen. The 185R15 Michelin versions carry TL tubeless markings, while 155R13 includes at least one tubeless-marked tire and other versions that vary by product marking. The 155R15 size clearly varies by product, with both TT tube-type and TL tubeless-marked versions present. Bias-ply 560-13 and 560-15 products here do not carry the same explicit tube markings in every case, so the individual sidewall marking should be checked before installation.

The practical rule is simple: do not assume all tires in the same Fairthorpe size handle tubes the same way. Tube choice should match the exact tire and the wheel being used, especially on older wheels where the rim design may influence whether a tubeless tire is appropriate in practice. Confirm the tire's own sidewall marking and make sure the valve stem, flap, and wheel condition all suit the final setup.

Within each 1961 Fairthorpe model pair, the two tire choices share the same rim diameter. The Electrina's 155R13 and 560-13 both fit 13-inch wheels. The Electron's 155R15 and 560-15 both fit 15-inch wheels. The Zeta's 185R15 and 6.50-15 both fit 15-inch wheels. That means the original wheel diameter remains consistent within each model even when construction changes from bias-ply to radial.

Wheel diameter compatibility is only the first check, though. Wheel width still needs to line up with the exact tire's approved range, and that can vary within the same nominal size depending on brand and construction. On a 1961 Fairthorpe, the safest approach is to verify the actual wheel width on the car before assuming the original wheels are suitable for every radial and bias-ply alternative that shares the same rim diameter.

A 1961 Fairthorpe should be stored clean, dry, and away from direct sunlight, electric motors, welders, furnaces, and other ozone-producing equipment that can accelerate rubber aging. Tire pressure should be kept at a normal stored level, and the car should be moved periodically or supported in a way that avoids letting one section of the tread carry the load for months at a time. Bias-ply tires tend to take a temporary flat spot more readily during long static storage than radials, so storage habits matter even more on the bias-ply sizes used across the Fairthorpe range.

For owners who keep a 1961 Fairthorpe parked through winter or between events, storage is part of tire preservation rather than an afterthought. A fitted spare should receive the same protection as the road tires, since it often goes untouched for years. When the car comes back into service, inspect the tread, sidewalls, and valve stems before driving instead of assuming a low-mileage collector tire is automatically ready for use.

On a 1961 Fairthorpe, tire life should be judged more by age and condition than by miles driven. Collector cars often cover so little annual mileage that tread wear is not the limiting factor. A sensible routine is to begin evaluating tires closely once they reach roughly five to seven years of age and to treat the ten-year point as a strong replacement consideration regardless of remaining tread depth. The DOT date code on the tire helps establish that timeline.

That age-based approach is especially important on a small British specialty car that may spend long periods parked between drives. Rubber hardening, sidewall checking, and loss of flexibility can develop even when the car appears lightly used. When evaluating a 1961 Fairthorpe, consider how the car has been stored, how often the tires have been heat-cycled, and whether the sidewalls still look and feel healthy enough for the kind of driving you plan to do.

Tires on a 1961 Fairthorpe should be inspected before every drive and again before any longer outing. Look for cracking, cuts, bulges, irregular wear, low pressure, and any sign that the tire has begun separating or losing air between uses. If the setup uses a tube-type tire or tube-equipped assembly, the valve stem condition becomes part of the inspection as well. The spare deserves the same attention, since a collector spare can age out quietly.

Frequent inspection matters because a specialty car like a 1961 Fairthorpe may sit far longer than a modern daily driver, and that inactivity can hide problems until the next road outing. A short visual check takes only minutes and often catches trouble before it becomes expensive or dangerous. On any older car, tire inspection works best as part of a broader pre-drive routine that also includes brakes, fluid levels, steering feel, and wheel-fastener security.

For a 1961 Fairthorpe Electron, the period-correct construction type would ordinarily be bias-ply rather than radial, which aligns with the 560-15 fitment available for that model. The Electron also has a 155R15 radial option, but radial construction reflects a later-style driving choice rather than the default construction most early-1960s specialist British sports cars would have worn when new. No single original-equipment brand should be assumed without period literature, surviving factory material, or model-specific club guidance.

That makes 560-15 the natural starting point for an originality-minded Electron restoration, especially when sidewall appearance is part of the judging standard or overall presentation goal. If the car is being restored for touring rather than strict originality, the 155R15 radial becomes part of the conversation. For final confirmation on market-specific or owner-delivery variations, a Fairthorpe registry or marque specialist is the best next source.

Correct tire fitment matters on a shown 1961 Fairthorpe because judges and knowledgeable enthusiasts often notice size, construction type, and sidewall treatment immediately. A model that should present as an early-1960s car on bias-ply tires can lose authenticity points if it appears on a modern-looking radial, and the reverse is also true for owners who are not seeking originality but want a car that looks internally consistent. Sidewall styling can matter almost as much as the basic size.

For concours-minded owners, the best approach is to define the target before buying tires: factory-correct restoration, period touring car, or a tasteful road-driven presentation. That choice determines whether construction, whitewall width, blackwall simplicity, or even a redline treatment makes sense for the car. Event-specific standards can vary, so it is wise to check with the relevant show organizers or marque community before settling on the final combination.

For the 1961 Fairthorpe Zeta, both Michelin XVS and Coker Classic cover the 185R15 radial size, but they differ in sidewall presentation and some published specifications. Coker Classic offers a redline 185R15 with a 5.00 to 6.50-inch rim-width range and a maximum load of 1,355 pounds at 35 psi. Michelin XVS appears in blackwall and narrow whitewall forms, with H-rated 185HR15 versions to 130 mph and a V-rated 185VR15 version to 149 mph, generally across rim widths from about 4.5 to 6.50 inches depending on version.

The choice comes down to the look and road profile you want for the Zeta. An owner chasing a sportier period appearance may be drawn to the redline treatment, while a more understated or European-touring look points toward the Michelin blackwall or narrow whitewall versions. Because the speed ratings and wheel-width ranges differ by version, the final decision should consider both the car's visual theme and the wheel dimensions already on the car.

1961 Fairthorpe tires can be suitable for highway use when they are the correct size, in sound condition, and operated within the limits of their construction and speed rating. Among the radial options, 155R13 appears in H-rated form to 130 mph, 155R15 appears in T-rated form to 118 mph and H-rated form to 130 mph, and 185R15 appears in H-rated form to 130 mph and V-rated form to 149 mph depending on the tire. Bias-ply sizes are a different driving experience and should be treated with the expectations appropriate to bias-ply construction.

In real-world use, a 1961 Fairthorpe's braking, suspension, steering, and general age are often more limiting than the tire's published top-speed symbol. Safety on the highway comes from the whole package: fresh rubber, proper inflation, a sound front end, and realistic speeds for a small early-1960s British sports car. A well-prepared Fairthorpe can be enjoyable on modern roads, but preparation matters more than simply choosing the highest speed letter available.

Inflation pressure on a 1961 Fairthorpe should be matched to the exact tire size and the manufacturer's guidance for that tire, not borrowed from a different size in the range. Some of the available tires include published load-and-pressure figures: 560-13 reaches 850 pounds at 30 psi, 560-15 reaches 970 pounds at 32 psi, 155R15 reaches 1,045 pounds at 44 psi on one version, and 185R15 reaches 1,355 pounds at 35 psi on one version. Those figures are tire ratings, not blanket recommendations for every Fairthorpe application.

The best practice is to start with the original vehicle guidance for the correct model and then confirm that your chosen reproduction or radial tire's operating range supports that use. A 13-inch Electrina tire should not be inflated by copying a Zeta figure, and a bias-ply setup should not automatically use the same pressure logic as a radial. Pressure tuning on a lightweight specialty car is part fitment science and part careful road testing.

Before a longer drive in a 1961 Fairthorpe, inspect every tire for sidewall cracking, tread separation, punctures, embedded debris, bulges, and uneven wear, then verify pressure when the tires are cold. Check the valve stems, and if the car runs a tube-type setup or tube-equipped assembly, pay close attention to any slow air loss or stem deterioration. The spare should be checked as seriously as the road tires, since an aging spare is common on collector cars.

Tires are only one part of the pre-drive picture on a 1961 Fairthorpe, but they are among the easiest items to inspect thoroughly before departure. After the tire check, a sensible routine includes wheel-fastener security, brake feel, fluid levels, cooling condition, and steering response. On a rare low-volume British car, a few minutes of preparation before a trip can prevent far more inconvenience than it takes to perform the inspection.