Honda Cb400n (1981)
1981 Honda Cb400n
CarHunch analysed 151 real MOT records for the 1981 Honda Cb400n. This breakdown of actual test outcomes — pass rates, defect profiles, mileage data — isn't published anywhere else.
The 1981 Honda CB400N falls just short of the UK average with a 77.8% pass rate against the national 80%, suggesting these bikes are reasonably reliable but slightly more prone to failures than typical. With just 11.3% ever recorded a dangerous defect, safety concerns are modest for a machine now 43 years old.
These machines average only 31,640 miles—remarkably low for their age, indicating most survivors have been cherished rather than commuted hard. The typical bike accumulates 1.11 failures and 2.8 advisories per test, pointing to wear in consumables and aging electrics rather than structural problems. Before buying, get a pre-purchase inspection to assess fuel system condition and wiring integrity, both common culprits on vintage Honda fours this age.
What to check before buying a 1981 Honda Cb400n
Practical pre-purchase checks for this age and model.
- 📋 Check the full MOT history. Look for recurring advisories — slow-building issues like corrosion or brake wear patterns show up years before they become failures. Enter the reg below for a full AI analysis.
- 🔍 Inspect for corrosion in person. Brake pipes, sills, subframes, and chassis legs. Surface rust is normal at this age; structural rust is a serious problem that's expensive to fix and can fail an MOT.
- 🛞 Check tyres and brakes. The most common advisory items at this age. Budget for replacement if they're near the limit — factor this into your offer price.
- 📄 Run an HPI check. The MOT history won't show outstanding finance, insurance write-offs, or stolen status — an HPI check will.
Before you buy a Honda Cb400n
MOT history is one piece of the puzzle. These checks can reveal what CarHunch can't.
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Mileage Distribution
Most 1981 Honda Cb400n vehicles sit in the blue band. If the car you're looking at is outside it, it's either unusually low or high mileage for its age.
Half of all 1981 Honda Cb400n vehicles fall between 19,341 and 39,181 miles.
1981 Honda Cb400n — Still on the Road
22 vehicles still getting MOTs in 2021 — 58% of the peak remain.
Based on vehicles from this manufacture year that had at least one MOT test in each calendar year. Data from 2014–2021.
MOT History Averages
Most Common MOT Issues — 1981 Honda Cb400n
Based on actual MOT test records for this model. Percentage shows how often each item appears across all vehicles in this cohort.
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17.7%
Rear Tyre worn close to the legal limit
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14.7%
Front Tyre worn close to the legal limit
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14.4%
Drive chain slightly loose
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14.1%
Drive chain worn but not considered excessive
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13%
Rear wheel bearings have slight free play
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9.5%
Nearside Front shock absorber has light misting of stanchion
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9.5%
Headlamp aim too high
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8.7%
Exhaust is leaking but is not excessively noisey
Data covers a 3-year window centred on 1981. Counts include advisories and failures.
Found a specific Honda Cb400n?
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