Five iconic Triumph twins and the spares they really need

Five iconic Triumph twins and the spares they really need

Spring roads are drying, classic show season is almost here, and Britain’s Triumph twins are warming up in sheds across the country. Few sounds beat a well-set 360-degree twin on song, and the best way to enjoy that is to give your machine a small, sensible refresh before the first long ride.

This guide spotlights five beloved Triumph twins, with quick ways to identify them, the traits they are known for, and the spares that typically bring them back to their crisp, confident best after a winter lay-up. It is part celebration, part practical checklist from a workshop that lives and breathes Meriden-era twins.

If you are new to Triumphs or returning after a few seasons away, the model tips below will help you order the right parts first time. If you are experienced, consider it a friendly nudge toward those little jobs that transform starting, idling and oil control.

How to identify classic Triumph twins at a glance

Triumph made steady, evolutionary changes. A few cues help you pin down what you are looking at, and what it needs.

• Badges and tank trim: The earliest postwar twins often wear raised script or small tank emblems; later bikes use bolder “Triumph” tank badges and side-panel decals. If in doubt, compare your tank and side covers to period-correct references and new old stock style items in a reputable catalogue. Fresh, heritage-correct Triumph badges and Triumph decals are worth fitting when restoring the look after mechanical work.

• Engine and gearbox: Pre-unit bikes, such as the 5T Speed Twin and early Tiger 100, have separate engine and gearbox casings with a primary chaincase between. Unit construction arrived on 650s for 1963, combining engine and gearbox in one set of crankcases. The 750 T140 family retains unit construction with a taller barrel and revised head.

• Frame and numbers: Matching engine and frame numbers are a bonus. The location and format of the stampings changed through the years, so consult a reliable Triumph numbering guide if you are unsure. The T120 and TR6 moved to the single-downtube oil-in-frame layout for the 1971 model year, a quick visual tell.

If you need help confirming what you have, a quick phone call often beats guesswork. Monty’s team speaks this language every day and will happily talk through casting marks, gearbox covers and odd brackets.

The five icons and what to check before the first ride

Here are five enduring Triumph twins, what makes each special, and the common refresh items that keep them running sweetly.

5T Speed Twin (500, pre-unit)

The motorcycle that set the pattern. Smooth, eager and lighter on its feet than later 650s.

Typical spring refresh:

• Plugs, points and condenser, plus a careful check of the advance unit for lazy return.
• Amal Monobloc fuel service; float needle and seat, pilot circuit clean, and a fresh air filter element.
• Primary chain tension and oil level, gearbox oil change, and new clutch springs if the take-up is grabby.
• New throttle cables to guarantee a clean snap-back, and a proper inspection of Lucas electrics and earths.

Known quirks: Worn slides and rich running after storage are common, so budget for slide and needle renewal when you order your Amal bits. Oil leaks around primary and pushrod tubes respond well to fresh gaskets and seals fitted to clean faces.

T110 (Tiger 110, 650, pre-unit)

A performance step above the 6T, and a favourite for period two-up touring thanks to its strong midrange.

Refresh priorities:

• Ignition refresh as above, plus a coil test if starting feels stubborn when hot.
• Primary chain and clutch plate check; uneven take-up often vanishes with a true basket and correct springs.
• Brake shoes and cables. Many T110s wake up dramatically with fresh linings and properly routed cables.

Known quirks: The T110 rewards careful carburation. If it coughs on pick-up, start with standard jetting then make small moves richer on modern fuel.

T120 Bonneville (650, unit)

Arguably the most famous Triumph motorcycle, the T120 is the twin-carb crowd pleaser. Steve McQueen is closely linked with the TR6 Trophy for off-road work, but the Bonneville name defines the road-going dream.

Refresh priorities:

• Twin Amal Concentric carburettors cleaned, float heights set, slides checked for wear. Balance the throttle lift carefully.
• New cables across throttle, clutch and front brake. A sticky cable ruins the crisp feel that makes a Bonnie sing.
• Oil and filter change, timing check, and a new chain and sprockets if the rear feels notchy.
• Fork oil and gaiters if perished; a surprising number of rattles are cured up front.

Known quirks: The T120 thrives on methodical set-up. Start from a known baseline for jets and needles, then fine-tune on the road with notes. Many owners cure flat spots with a slightly richer main and a tidy pilot circuit.

TR6 Trophy (650, unit)

Single-carb sibling to the Bonneville, with strong manners off road and on. The TR6 that Bud Ekins and Steve McQueen rode in desert events built a legend for tractable power and clean torque.

Refresh priorities:

• A full carburettor service is simpler with a single Concentric, so do it properly: new float needle, fresh gaskets, and idle mixture set warm.
• Magneto or coil ignition checks depending on year; a sound condenser and healthy points are priceless.
• Chaincase inspection and a primary chain that is neither slack nor tight at the tight spot.

Known quirks: Many TR6s wear period exhausts that can go thin or crack at the balance. Inspect hangers and clamps, and fit quality exhaust fittings to stop leaks that mimic carb problems.

T140 Bonneville (750, unit, oil-in-frame)

The 1970s workhorse. Bigger lungs, disc brakes, and a riding position that suits real miles. Often the most usable of the bunch when maintained.

Refresh priorities:

• Full ignition service on points models, and a careful charging system check. Poor earths and tired rectifier/regulator units create charging gremlins that masquerade as carb faults.
• Concentric carburettors cleaned and re-jetted if ethanol has been sitting; manifold rubbers crack with age, so replace on principle if they look tired.
• Front and rear brake service. New pads or shoes, fresh fluid where applicable, and a clean of sliding pins or cams.
• Primary chain alignment and a fresh clutch plate set if the take-up is inconsistent.

Known quirks: The 750 top end likes clean oil and sensible warm-up. Keep an eye on rocker feed unions and banjos for weeping; dress threads and fit proper washers.

The spares that make first rides effortless

If your Triumph has been resting, a light refresh transforms the way it starts, idles and pulls. Build a simple bench kit:

• Plugs of the correct grade, fresh points, condenser and a sound advance unit. Lucas-pattern parts from trusted makers reduce roadside faults.
• Carburettor service items: gaskets, float needle and seat, slide if worn, and new air filter. For many, authentic Amal Concentric carburettors and spares are the straightforward route to factory feel.
• Cables: throttle cables first, then clutch and front brake. Correct lengths and clean routing give a crisp control feel.
• Chains and brakes: primary, rear and timing chains checked or renewed; fresh brake shoes or pads, cables or hoses as needed.
• Oils and gaskets: engine oil, gearbox oil where separate, primary case oil, plus sump, primary and rocker-box gaskets.

If you want a one-stop browse, start with Triumph motorcycle parts in the shop and zero in by model year. For a deeper model overview when identifying an old Triumph motorcycle, the Triumph motorcycle models page is a useful orientation.

Provenance matters, modern manufacturing and heritage supply

Owners often ask which Triumphs are made in the UK today. Current-production Triumph Motorcycles designs and develops bikes in Hinckley, with some assembly and manufacturing in the UK and significant global production in Thailand and other facilities. That modern footprint sits alongside a healthy heritage supply chain in Britain that keeps Meriden-era twins on the road. Monty’s prioritises British manufacturers where possible and carries L F Harris parts chosen to original factory tolerances so classic machines fit and feel right. In short, the new bikes are a modern global effort, while the spares that keep your pre-1988 twin honest can still be proudly British in origin.

Quick identification and spares links

• Need pre-unit and unit Tiger references while ordering? See Tiger 100 Triumph and Triumph Tiger 90 coverage in the Triumph Tiger models section.
• Looking for a deep T-series view, including T110 Triumph and T160 Triumph references for cross-checking parts families? Explore the Triumph T-series overview.

You can also call the workshop for friendly advice on jetting, cables and Lucas-style electrics, or to ask about stock that is not shown online. Many everyday motorcycle spares are on the shelf in Cornwall for fast dispatch during the week.

FAQ

What are Triumph’s most iconic models?
Among many, the 5T Speed Twin, T110 Tiger 110, T120 Bonneville, TR6 Trophy and T140 Bonneville are standouts for British road and competition heritage.

What is the most famous Triumph motorcycle?
The T120 Bonneville is the best-known name worldwide, thanks to its twin carbs, performance image and long production run.

What Triumph did Steve McQueen ride?
Steve McQueen and his friend Bud Ekins famously rode TR6 Trophy models in desert events. The jump in The Great Escape used a disguised Triumph for filming, widely said to be a TR6-based machine.

How do I identify an old Triumph motorcycle?
Check unit versus pre-unit engine layout, look for oil-in-frame on early 1970s bikes, compare tank badges and side-panel decals to period patterns, and verify engine and frame numbers against a model-year guide.

Which Triumphs are made in the UK?
Modern Triumphs are designed and developed in the UK, with some models built or assembled in Britain and others produced in overseas plants. The exact mix varies by model and year.

A last word before you wheel it out

Classic Triumphs reward small, careful jobs done with the right spares. Fresh plugs and points, a clean Concentric, new throttle and clutch cables, sound brakes, correct oils and tidy gaskets are the difference between coaxing and first-kick confidence. If you want to browse by theme, start with British motorcycles Triumph on the home page, or jump straight to motorcycle carburettors for Amal jets and fittings. Prefer to talk it through? Ring 01822 617010 during opening hours and we will help you get the parts you would fit in the workshop yourself.