This is a CB 400 registered 1987 but has been upgraded, It looks like a 1992 onwards Honda CB 400 SF.
I don't know much about the upgrade or who ,when or where it was done.
This bike is friends motorbike which cannot ride any more, I used the bike my self and it drives and is a very nice bike to ride. No kilo on the speedo because the rev-counter and speedometer were renewed last year the bike has been standing for over a year.
It very hard to price a Bike like this but the owner paid 90,000 3 years ago.
All the entries in the green book are correct and it can be tax and insured.
Below are the specifications for the original CB400 and the SF.
The main difference is the BHP and now liquid-cooled.
CB400 SF ( super Four )
Predecessor Honda CB400N
NC42E Four-stroke, inline-4, DOHC, 16 valves, liquid-cooled
Bore / stroke
55 mm × 42 mm (2.17 in × 1.65 in)
39.5 kW (53.0 hp) @ 10,500 rpm
38 N⋅m (28 lbf⋅ft) @ 9,500 rpm
6-speed, wet multi-plate clutch, chain drive
1,410 mm (56 in)
Dimensions L: 2,040 mm (80 in)
W: 725 mm (28.5 in)
H: 1,070 mm (42 in)
Seat height 755 mm (29.7 in)
Weight 200 kg (440 lb) (wet)
Fuel capacity 18 L (4.0 imp gal; 4.8 US gal)
Model: Honda CB 400 F
Rating: 78.1 out of 100. Show full rating and compare with other bikes
Engine and transmission
Displacement: 408.00 ccm (24.90 cubic inches)
Engine type: In-line four, four-stroke
Power: 37.00 HP (27.0 kW)) @ 8500 RPM
Top speed: 158.0 km/h (98.2 mph)
Bore x stroke: 51.0 x 50.0 mm (2.0 x 2.0 inches)
Valves per cylinder: 2
Fuel control: Overhead Cams (OHC)
Cooling system: Air
final drive: Chain
Chassis, suspension, brakes and wheels
Front tyre: 3.00-18
Rear tyre: 3.50-18
Front brakes: Single disc
Rear brakes: Expanding brake
Physical measures and capacities
Weight incl. oil, gas, etc: 184.0 kg (405.7 pounds)
Fuel capacity: 14.00 litres (3.70 gallons)