Triumph Bonneville T120
Triumph's flagship modern-classic — 1200cc parallel twin with traditional 1959 Bonneville styling. Bigger, smoother and more refined than the T100 sibling. 80bhp, 105Nm torque, twin shocks, spoked wheels, traditional round headlight. Built in Hinckley, UK. Hand-finished details (brushed alloy mudguards, twin-clock dashes, peashooter exhausts) justify the price over the smaller T100. Genuinely premium feel without going to specialty brands like Norton.
- Engine
- 1200 cc
- Power
- 80 PS
- Weight
- 236 kg
- Seat height
- 790 mm
- A2 licence
- —
Liquid-cooled SOHC 8-valve parallel-twin
wet
The short version
Forecourt score
Value 61 · Insurance 66 · Theft 65
The Triumph Bonneville T120 holds its value about as well as most bikes (around 26% lost over three years, against the 25-32% bike norm) and costs about average to insure (around £460/yr typical). Theft risk is moderate.
A bike-specific blend of value retention, insurance and theft risk (weighted 40/35/25). Bikes carry no MOT reliability data, so reliability isn't scored. Higher is better.
Pick your version
Estimates are tuned to the version you choose.
Engine
Petrol · 1200cc
Power
80 ps
Torque
105 Nm
Weight
236 kg
Seat
790 mm
Transmission
6-speed manual
Economy
55 mpg
Standard T120 — 1200cc parallel twin, 80bhp, 6-speed. Twin shocks, spoked wheels, twin-clock dash. Premium Triumph build quality. 14.5L tank.
Tell us about the one you're looking at
Tidy and well looked-after for its age — the typical clean bike.
Estimated market value
£8,436
Range £7,592 – £9,280
HIGH CONFIDENCE
Holding value
Bikes hold value far better than cars — typical motorcycle 3-year depreciation is 25–32%, against cars' 40–50%. Some bikes (Hayabusa, Gold Wing, classic Z1000) actually appreciate in the 7–15 year zone as cult demand outstrips supply.
New
£12,200
At 5 years
£7,808
At 10 years
£5,612
Value loss by phase
Each band shows the share of original value lost during that window — not cumulative. Appreciation (green, marked +X% gained) is real for bikes that develop cult status.
UK new price by year
How we estimate this
Phase depreciation derived from observed UK used-bike pricing — classified ads, dealer asking prices, and end-of-auction figures. Bike residuals depend heavily on theft history, service-stamp count, and crash-damage signatures. The figures here are indicative for clean, fully-stamped examples.
What it costs to own
Indicative running costs at 8,000 miles a year — the UK rider average. Chain-drive bikes carry a chain/sprocket consumable line; tax (typically £25–£100/yr) and depreciation are excluded — see the section above for value retention.
3-year total
£2,270
Per year
£757
Per mile
£0.09
Service costs assume independent specialist labour and OE parts. Tyre intervals reflect typical UK road riding — track-day usage burns through rear tyres in <2,000 miles. Fuel uses the variant MPG at £1.45/L. Lower-mileage riders see proportionally lower totals; higher-mileage commuters pay roughly linearly more.
Estimated insurance
ABI motorcycle scheme · Comprehensive · 5 yr NCB
Indicative annual comprehensive premiums for this bike. Bike insurance is far more sensitive to licence tier and rider age than cars — pick the combination closest to your circumstances.
Licence
Age
No-claims bonus
5 yearsRisk profile
Estimated annual premium · typical, age 30-39
£460/ year
Roughly £38 per month
Typical
Suburban postcode, 3+ years NCB, standard security (Thatcham chain + disc lock), no recent claims.| Age band | Lower risk | Typical | Higher risk |
|---|---|---|---|
| Age 17-21 | £759 | £1,012 | £1,417 |
| Age 22-29 | £466 | £621 | £869 |
| Age 30-39Selected | £345 | £460 | £644 |
| Age 40-49 | £304 | £405 | £567 |
| Age 50+ | £276 | £368 | £515 |
How we estimate this
Premiums combine licence tier, rider age, no-claims bonus and a risk-profile multiplier on top of a bike-specific baseline. Bike insurance is materially more sensitive to licence tier (CBT / A1 / A2 / A) than car insurance, and young riders pay considerably more than older riders even on the same machine. Always get individual quotes before buying.
Theft risk
Bike-specific · Met Police + insurance reporting
UK bike theft rates are an order of magnitude higher than car theft. Nakeds and supersports lose more to professional gangs; large adventure bikes and tourers are statistically much safer.
Theft risk score · 1 to 4
2/4Medium risk
Medium risk
Some theft pattern, particularly in urban postcodes. Thatcham-approved chain plus disc lock recommended; secure overnight parking helps premiums.Theft hotspot postcodes
Postcode prefixes only; full London hot zone runs across E, N, NW, SE, SW, W boroughs depending on the model.
What this means for you
Premium Triumph with strong used demand — popular target. Chain + disc lock + cover essential overnight; garage if possible.
How we set this band
Bands derived from Met Police bike-theft reporting (most-stolen lists) cross-referenced with insurance industry underwriting data. Model + postcode are the two biggest factors in motorcycle theft risk in the UK, materially more than vehicle value.
What goes wrong
5 known issues · sorted by severity
Documented failure modes from UK owner forums, dealer service bulletins, and aggregated mechanic feedback. Mileages are approximate — different riders see different intervals depending on use and maintenance. Always address "high"-severity items before resale.
High severity
0
Medium
3
Low / cosmetic
2
| Severity | Part / issue | Cost |
|---|---|---|
| medium | Cam chain tensioner rattle Audible at cold start; replaceable at major service 20k+ mi | £300 |
| medium | Chain & sprockets 12-16k mi | £260 |
| medium | Exhaust corrosion (peashooter pipes) Chrome plating on header pipes corrodes faster than satin finishes 5-7 years | £500 pair |
| low | Front brake pads 10-14k mi | £90-110 |
| low | Battery every 4 years | £110-130 |
How we score severity
High — strands the bike or causes consequential damage if left. Medium — service item that affects ride quality or risks failure. Low — cosmetic or minor inconvenience. Costs are independent-specialist UK rates for parts and labour together; main dealer prices typically run 30–50% higher.
Safety recalls
Manufacturers occasionally issue safety recalls to fix a fault free of charge. You can check whether the Triumph Bonneville T120, or your exact vehicle, has any outstanding recalls on the official DVSA service.
Check on GOV.UKOpens the Driver & Vehicle Standards Agency recall checker. Choose the make, model and year of manufacture — no registration needed.
All variants
| Trim | Engine | PS | kg | Seat | A2-restrict? |
|---|---|---|---|---|---|
| Bonneville T120default | Liquid-cooled SOHC 8-valve parallel-twin, 1200cc | 80 | 236 | 790 | — |
| Bonneville T120 Black | Liquid-cooled SOHC 8-valve parallel-twin, 1200cc | 80 | 236 | 790 | — |
Strengths
- +Hinckley-built UK quality — hand-finished details
- +80bhp + 105Nm gives genuinely big-bike feel
- +Holds value well — strong used demand
- +10,000-mile service intervals (long for a parallel-twin)
- +Authentic 1959-styling without retro-replica feel
Watch-outs
- −Heavy (236kg wet) — feels it at parking-lot speeds
- −Chrome corrodes in UK winter without aftercare
- −Service costs higher than Japanese rivals
- −Comes with peashooter exhausts that decay aesthetically faster than satin