Honda CB1 Specs and Information (1989 to 1990 – aka CB400F NC27)

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Honda CB-1 NC27

1990 Honda CB1 (NC27)

Honda CB-1 Specs…..

The Honda CB-1 was a short lived but surprisingly popular (in the UK) naked, 400cc bike that was released in Japan between 1989 and 1990.
The bike was also known by it’s official Honda model code (NC27) and as the CB400F in some countries it was marketed in.

The CB1 was originally released in Japan, but was later also released in the USA and Canada.
The CB1 was a fairly ‘sporty’ feeling bike, with a small and compact design and an engine based on the fully faired CBR400 NC23 (although the engine was de-tuned for the CB-1).

Need parts for your CB1? Honda CB-1 spares on Amazon…

A little bit about the Honda CB-1…..

Basic model info…

Manufacturer: Honda
Model: CB-1
Honda model code: NC27
AKA (also known as): CB1, CB400F
CC: 399cc
Engine type: Inline twin cylinder (4 stroke)
Countries officially released in: Japan, United States and Canada (grey import in the UK)
Years in production: 1989 to 1990
Style of bike: Naked bike
Insurance: Group 8 (of 17) – Need bike insurance? Get a quote at

Models and years (in the UK)

Note: The CB-1 was a ‘grey import’ in the UK, which means it was never officially released by Honda in this country.
The bike was available here, but not new from Honda (models available would have been registered in other countries where it was officially released and imported 2nd hand to the UK by importers, dealers and private individuals).

CB-1 (1989 to 1990)…..
Description: Unfaired 399cc bike with 17 inch front and rear wheels, Showa 41mm front forks, single front disc brake and a engine based on a de-tuned NC23 engine.
Available colours: Red, yellow and blue
CB-1 front view

Honda CB1 front view. Fitted with aftermarket headlights.

Engine and gearbox specs…..

Displacement: 399cc (24.3 cubic inches)
Engine type: Inline 4 cylinder
Engine weight: 57kg (126lbs)
Stroke: 4 stroke
Bore×Stroke: 55.0 x 42.0mm (2.17 x 1.65 inch)
No. of cylinders: 4 (inline)
Firing order: 1 – 2 – 4 – 3
Cam shaft configuration: DOHC (double overhead cam – gear driven)
Compression ratio: 11.5:1
Cylinder compression pressure: 12.5 to 13 bar (182 to 188 psi)
Valves: 16 valve (4 per cylinder)
Spark plug: NGK CR8EH-9 (x4)

Note: Honda recommend using the NGK CR9EH-9 spark plug instead of the standard CR8EH-9 for extended, high speed riding…….and no, on the road you won’t be fast enough for this! 😀

Spark plug gap: 0.8 to 0.9mm
Engine oil system: Forced pressure from a wet sump in bottom of the engine
Oil pump: Trochoid type oil pump

Note: A Trochoid oil pump has an inner and outer rotor with different numbers of teeth (e.g. the outer rotor can have 5 teeth and the inner can have 4 teeth). The difference in teeth creates uneven spaces inside the pump which causes the oil to move to fill the gaps as the inner rotor rotates (example below, not from a Honda engine).

Trochoid pump

Unfortunately, these pumps do suffer from pitting if the incorrect oil has been used in the engine (e.g. car oil).

Engine oil: 10w40 API SG or higher

Note: You can use any grade oil in the CB1 engine (mineral, semi synthetic or full synthetic). Although fully synthetic is the best and will offer the best protection for your engine, we normally recommend a semi synth as it’s a good balance between engine protection and price. More info…

Engine oil capacity (with filter change): 3.1 litres
Engine oil capacity (without filter change): 2.9 litres
After engine rebuild/disassembly: 3.5 litres
Engine oil drain bolt location: Bottom/right of the engine oil sump (right as your sitting on the bike)
Oil filter type: Canister type
Oil filter: Hiflo HF303 / Filtrex OIF006
Oil filter torque: 10nm
Oil pressure: 4.9 bar / 71psi (at oil pressure switch)
Clutch: Wet (oil immersed) multiplate clutch
Clutch operation: Mechanical / cable
Clutch lever free play: 10 to 20mm
Gearbox: 6 Speed manual
Gearbox configuration: 1st Gear down, 2nd to 6th gears up, neutral between 1st and 2nd gears (1 – N – 2 – 3 – 4 – 5 – 6)
Gear change operation: Pedal operated by left foot
BHP (claimed!): 55 bhp (@ 10,000 rpm)
Torque (claimed!): 29 ft/lb (@ 9,500 rpm)
Top speed (claimed): 118mph

Note: BHP, torque and top speed figures are ‘claimed!’ based on Honda marketing stuff (it’s not uncommon for manufacturers to inflate these figures as it helps sell more bikes!).

Piston ring to cylinder bore clearance: 0.10mm (max service limit)
Valve clearance (inlet): 0.12 – 0.18mm (when cold)
Valve clearance (exhaust): 0.17 – 0.23mm (when cold)
Idle speed: 1,300rpm (1,400rpm for California models – +/- 100)
CB-1 engine - right
CB-1 engine - left

Honda CB1 399cc, inline 4 cylinder engine

Cooling system stuff…..

Cooling system: Liquid cooled
Cooling system capacity (complete system – radiator, engine and reservoir): 1.8 litres
Cooling system capacity (engine and radiator): 1.5 litres
Cooling system capacity (reservoir only): 300ml
Water pump location: Bottom/left of engine (just infront of the front sprocket cover)
Coolant reservoir location: Front/right, underneath the seat (between the back of the tank and the battery)
Water pump drain bolt location: Bottom of the water pump (lowest short bolt on the pump)
Thermostat begins to open at: 80 to 84 degrees C
Thermostat fully open at: 95 degrees C
Fan motor switch turns on at: 98 to 102 degrees C
Fan motor switch turns off at: 93 to 97 degrees C
CB1 NC27 side view

Left side view of a 1990 Honda CB1

Final drive stuff…..

Final drive: Chain
Front sprocket: 15 teeth
Front sprocket nut tightening torque: 55mm
Rear sprocket: 37 teeth
Rear sprocket nut tightening torque: 65mm
Chain pitch/length: 525 pitch / 104 links
Chain free play: 15 to 25mm

CB-1 HF303 oil filter

Honda CB1 (NC27) canister type oil filter (Hiflo HF303)

Carb, fuel and oil stuff…..

Fuel system: Carburetor
MPG (average): 44 miles per gallon (very approx)

There are variations in MPG between users, mainly due to different riding styles and areas (e.g. city riding vs open road)

Fuel tank capacity: 11.5 litres
Fuel tank reserve capacity: 3.5 litres
Fuel type: Unleaded petrol (91 octane grade – aka standard petrol from your local garage)
Carb make: Keihin CV32 (4x)
Carb type: VG06B (VG06C in California)
Pilot screw opening: 1 turn
Throttle grip free play: 2 to 6mm
Engine oil: 10w40 API SG or higher

Note: You can use any grade oil in the CB1 engine (mineral, semi synthetic or full synthetic). Although fully synthetic is the best and will offer the best protection for your engine, we normally recommend a semi synth as it’s a good balance between engine protection and price. More info…

Engine oil capacity (with filter change): 3.1 litres
Engine oil capacity (without filter change): 2.9 litres
After engine rebuild/disassembly: 3.5 litres
Engine oil drain bolt location: Bottom/right of the engine oil sump (right as your sitting on the bike)
Engine oil drain bolt tightening torque: 35nm
Oil filter type: Canister type
Oil filter: Hiflo HF303 / Filtrex OIF006
Oil filter torque: 10nm
Oil pressure: 4.9 bar / 71psi (at oil pressure switch)
CB-1 Cockpit layout
CB1 clocks

Layout of the clocks and handlebars on a CB-1 (NC27)

Electric stuff…..

Ignition type: Electronic CDI
Starter: Electric start
Electrical system voltage: 12 volts
Battery voltage (fully charged): 12.8 volts
Battery amps per hour: 8 a/h
Battery will need charging if below: 12.5 volts
Battery charging current (normal): 0.9 amps on a 5 to 10 hour charge
Regulated voltage: 14 to 16 volts (@ 5000 rpm)
Spark plug: NGK CR8EH-9 (x4)

Note: Honda recommend using the NGK CR9EH-9 spark plug instead of the standard CR8EH-9 for extended, high speed riding…….and no, on the road you won’t be fast enough for this! 😀

Spark plug gap: 0.8 to 0.9mm
Spark plug tightening torque: 11nm
Spark plug ignition: 2 x coil
Battery: CTX9-BS / YTX9-BS / CBTX9-BS


  • The YTX9-BS battery is a 12 volt, 8 amp/hour battery and is length: 151mm width: 87mm height: 106mm in size (more info…).
  • The 1st letter(s) of the battery reference code are a manufacturers reference mark and may vary between different battery makes (different battery manufacturers use different 1st letters), so CTX9-BS, YTX9-BS and CBTX9-BS are all the same battery just from different manufacturers (more info…).
  • Also…… Avoid buying the cheapest of the cheap type batteries online as they have a horrendous failure rate (and they can be a bug!er to post back when it fails.

CB-1 battery

Honda CB-1 battery (YTX9-BS)

Shocks, brakes and wheel specs…..

Front wheel type: 3 spoke cast wheel
Front tyre size: 110/70-17
Front tyre pressure: 33psi (2.3 bar)
Front wheel spindle torque: 60nm
Front wheel spindle clamp bolt torque: 22nm
Rear wheel type: 3 spoke cast wheel
Rear tyre size: 140/70-17
Rear tyre pressure: 36psi (2.5 bar)
Rear wheel spindle torque: 90nm
Front brake: Single hydraulic disc brake with 2 piston caliper
Front brake disc: 310mm single disc. Part no: EBC MD1038RS (1x)
Front brake pad: EBC FA142 (1x)
Rear brake: Single hydraulic disc brake with 1 piston caliper
Rear brake pad: EBC FA140 (1x)
Rear brake disc: Single 240mm disc. Part no: EBC MD1020 (1x)
Brake fluid (front and rear): DOT 4 brake fluid
Front suspension: Telescopic forks (Showa)
Front fork stanchion diameter: 41mm
Recommended fork oil: 10w (medium weight) fork oil
Fork oil volume: 510 ml (per fork)
Front wheel travel (up/down):
Rear suspension: Single rear monoshock
Rear shock type: Gas filled (nitrogen) with preload adjustment
Rear shock top mounting bolt torque: 45nm
Rear shock bottom mounting bolt torque: 45nm
Rear shock lower joint bolt torque: 68nm
Rear wheel travel (up/down): 110mm
CB-1 front wheel

110/70-17 Front wheel with single front disc on a Honda CB-1

Weights, measures ‘n stuff…..

Overall length: 2,035mm
Overall width: 705mm
Overall height: 1,025mm
Wheelbase: 1,370mm
Seat height: 775mm
Footpeg height: 335mm
Ground clearance: 130mm
Dry weight (no oils, fluids etc): 170kg
Kerb weight (with oil, coolant etc – approx): 183kg
Max weight capacity: 157kg
CB1 top

Top view of a 1990 Honda CB400F NC27

Useful torque settings…..

General nuts, bolts, screws and fastners…
5mm bolt and nut: 5nm
6mm bolt and nut: 10nm
8mm bolt and nut: 22nm
10mm bolt and nut: 35nm
12mm bolt and nut: 55nm
5mm screw: 4nm
6mm screw: 9nm
6mm flange bolt (with 8mm head): 9nm
6mm flange bolt (with 8mm head): 12nm
8mm flange bolt and nut: 27nm
10 mm flange bolt and nut: 40nm
Specific/important nuts, bolts and fastners…
Oil pressure switch: 12nm
Oil drain bolt: 35nm
Oil filter: 10nm
Spark plugs: 11nm
Front sprocket nut: 55mm
Rear sprocket nuts: 65mm
Front wheel spindle torque: 60nm
Front wheel spindle clamp bolt torque: 22nm
Rear wheel spindle torque: 90nm
Front brake caliper bolt: 30nm
Rear brake caliper bolt: 30nm
Cylinder head cover bolt: 10nm
Camshaft holder bolt: 12nm
Alternator flywheel bolt: 85nm
Engine mount nut (front): 40nm
Engine mount nut (rear/upper): 50nm
Engine mount nut (rear/lower): 50nm
Front brake disc bolt: 30nm
Front caliper bracket bolt: 27nm
Front caliper bolt: 23nm
Rear brake disc bolt: 40nm
Rear caliper bolt: 23nm
Rear shock top mounting bolt: 45nm
Rear shock bottom mounting bolt: 45nm
Rear shock lower joint bolt: 68nm
Front NC27

Front view of a Honda CB1 (NC27) with aftermarket ‘streetfighter’ headlights

Service stuff…..

Servicing your bike? You’ll need tools and CB-1 parts…
Engine oil
Engine oil change frequency: Every 12,800km (approx 7,900 miles) or 12 months
Engine oil: 10w40 API SG or higher

Note: You can use any grade oil in the CB-1 engine (mineral, semi synthetic or full synthetic). Although fully synthetic is the best and will offer the best protection for your engine, we normally recommend a semi synth as it’s a good balance between engine protection and price. More info…

Engine oil capacity: 3.1 litres
Engine oil drain bolt location: Bottom/underneath of the engine
Oil filter: Hiflo HF303 / Filtrex OIF006
Oil filter torque: 10nm
Chain drive
Final drive chain check frequency: Now repeat after me… ‘I MUST LUBE MY CHAIN LITTLE AND OFTEN!!’
At least once a week…
Chain and sprocket size: 104 link / 525 pitch Chain, 15 tooth front and 37 tooth rear sprocket
Hydraulic brake system (front and rear)
Brake fluid check frequency: Check every 12 months or 6,400km (approx 3,900 miles)
Brake fluid change frequency: Change every 24 months or 19,200km (approx 11,900 miles)
Brake fluid: DOT 4 brake fluid
Fork oil
Front fork oil check frequency: Check every 12,000km (approx 7,456 miles) or 12 months
Recommended fork oil: 10w (medium weight) fork oil
Fork oil volume: 510ml (per fork)
Cooling system
Coolant check frequency: Check every 12,800km (approx 7,900 miles) or 12 months
Change every: 38,400 km (approx 23900 miles) or 24 months
Cooling system: Liquid cooled
Cooling system capacity: 1.8 litres
CB-1 back view

Back view of a 1990 CB-1 NC27

Frame number location…..

The frame number is stamped onto the right side of the headstock (the front part of the frame just below the handle bars).
There is also a information plate on the right of the bike, on the frame just behind the headstock and just below the tank.

Engine number location…..

On the right side of the engine crankcase, just behind where the clutch cable joins the clutch arm (the engine number usually starts ‘NC23….’.

Useless stuff…..

Although the CB-1 wasn’t a popular bike for Honda, it has proved popular in other countries where it was officially released and in countries, like the UK, where it was imported as a ‘grey import’.
The CB1 was released at a time when the market was changing and people weren’t looking for sporty. unfaired bikes and were looking for sportier, fully faired bikes (e.g. CBR400, CBR600 etc). This meant the CB1 was a hard sell for Honda. Officially, the bike was sold between 1989 and 1990, but it was available new up until 1992 in some countries at a discounted price to clear stock (the bike was known as the CB400F in the US).
The CB1 has proved popular with newer, 1st ‘big bike’ riders, couriers and, due to it’s smallish size and low seat height, shorter riders.
The sporty ride of the bike is achieved, it part, by the frame design and clip on handle bars (as opposed to more traditional handle bars used on many ‘naked’ bikes) and the use of an engine based on the CBR400RR NC23 engine. The CBR400 engine was de-tuned for the CB-1, with changes to the port lengths as well as smaller valves and lower compression ratio. Other changes were in the primary and secondary gear ratios which meant the 1st gear speed was reduced from 60 mph (in the CBR400) down to around 30 mph (although this meant the CB1 was quicker off the mark then the CBR400!).
Although never official in the UK, there have been many CB1’s with upgrades and extras over the years. Many have been modified with a CBR400 forks and front brake system, which converts the single front disc brake to a twin front disc brake, as well as braided brake hoses, performance and home made exhaust systems and other parts.

Buying advice…..

Firstly, if your thinking of buying one always HPI check it (there’s still loads about so no point risking getting stuck with a lemon!).
These are good, solid bikes and are ideal for 1st time ‘big bike’ riders as well as shorter (lady) riders. Mileage isn’t really anything to worry about (within reason!), but obviously a bike that’s had frequent oil changes is likely to be better.
As the bike was a naked/unfaired bike there’s wasn’t alot of fairing to damage and indicators, headlights etc could be easily replaced, if damaged, with aftermarket parts.

Obviously, the youngest of these bikes will be 27 years old now so if your buying you’ll need to check any metal parts, especially exhausts, forks and similar (also check the availability of parts as grey import bike aren’t always the easiest to get parts for!).
Although the CB-1 is fairly reliable (gear driven cams etc), there are a fair few ex courier and winter bike hacks around, which aren’t always a bad buy, but will invariably always need something doing to them.
Common part’s like reg/recs, brake pads, clutches, chain and sprocket kits, caliper pistons where shared between a few Honda models to these parts aren’t difficult or expensive to source.

Happy biking 🙂

Sources / Thanks to / Useful CB1 sites:

CB-1 article on Wikipedia Loads of helpful owners and info
Honda CB1 service manual (pdf)

If you’ve got any questions, comments or suggestions please feel free to leave them below 🙂

Disclaimer: The information on this page is correct to the best of our knowledge. But the info should NOT be taken as 100% accurate as we can, occasionally make mistakes!


41 responses to “Honda CB1 Specs and Information (1989 to 1990 – aka CB400F NC27)”

  1. I got a 1990 with 13k miles – love the bike. Great info! What were your reference sources for the specs?

    1. Reference sources are…..
      -Me (I’ve owned a few of these over the years)
      -Collection of old service and spec books
      -And there is a service manual available online for this bike (there’s a link to at at the bottom of the above article) 🙂

    2. FatKeanu Avatar

      I was 16 when I saw this at the dealership. I still want it and have been getting kinda serious about. Being 5’10” I wonder if it would be a good fit. Comfortable enough for longer rides. Any opinion?

      1. I have one. Im 5’11”. Im ok on the bike, but its more a fun bike than nice touring bike. My previous bike was a Vstrom 650 2014 that was very good bike for long traveling. Ilove my CB1 for short run…1h30 max. I can use all the power at full throtle and the feedback of the screaming 400cc 4 cylinder is like my older GSX750r when I was young! But not dangerous or fear to lost licences.
        I keep my CB1 for what it is….a litle very funny bike that can surprise many biker. I owned many sport and touring bike…but I can sold my CB1. Its like a toy, easy to ride, and there is nothing that sreaming like a 4 banger carburated a 13 500 tr/min lol.

      2. Simon Haddock Avatar
        Simon Haddock

        I am 5′ 10′ and have owned these bikes for years . Never a problem in fact , it’s an advantage -You’re tucked in more like being part of the bike and the with smaller height it’s quite wonderful with town use and being able to put your feet flat to the ground. The handling on these bikes is second to none , they are so well balanced- Even these days with modern bikes I have never felt the ability of the bike to be out classed by new machinery . Long rides , well this summer with almost every day being a biking day my long rides they were very long indeed . How about an average of 200 miles every day and never ever feeling the effects of any type of back ache or wrist ache … I have owned 100 plus motorcles since 1969 and will say in all honesty that there have only been very few bikes that have been able to outclass them in any way . Yep they aren’t the fastest bike out there but in all reality you don’t need that massive top end . I’ve owned bikes that can do 170 mph plus and always got frustrated that I couldn’t ever use that power ( only when I lived in Germany was I able to open the bikes up) but really after you do that a few times , that novelty wares off )…No the real rush is between 50 and 80 which is just perfect for these UK roads …One thing be wary of getting one of the old dispatch riders bikes , they were very popular in the early 90’s with the London boys who would thrash them around the city …Top tip . When on tick over that engine should sound sweet , because they don’t have a cam chain ( Direct drive Cam GearDrive ) so no rattles . Try if you can to get one of the MK1’s , they were built for the JDM and are of much higher quality re- alloy’s with a full factory made stainless steel system . The DVLA have confirmed to me that there are only 57 in total in the UK . Many of these being the USA/ Canadian model that were produced in 1991 . All bikes that came into the UK get reg as on a 1989 plate for convienience . They had a production run of only 22.000 and that was split into three batches . 10.000 -1989- 8.000 -1990 and the final year of production 1991 with only 4.000 made and these were for the USA/ Canada. These are the MK2 versions with a steel exhaust system , steel passenger foot rails. Black headlight surround , reflector strips on the forks and their clocks will be in MPH. As of summer 2022 there are only 7 MK1’s reg for the UK roads of which I own 3. They are rare and going up in value quickly , you will be hard pressed to find the MK1 . Back in Novemeber 2021 Classic Motorcycle Magazine did a main page review of the bike, with cover photo and up to that point you could get one in superb condition( original ) not restored for £1.500 because I did and was pleasantly surprised to find a few months later that the value of the bike had gone up by more than 100%. They are now worth on the classic scene a min of £3000 plus . They have to be original nothing changed ,no resto 100% factory spec . I have been lucky enough to find another one for my collection only last week – I now own 3 of the current 7MK1’s on UK roads so I can sell for what I like . There is no actual market value and they will only go up in value . I could sell my collection of all 3 for at least £9000 min . So good luck in finding one they are getting rarer and rarer as each year passes . Remember you will have to be able to fork out £3000 for a good one or you could get a MK 2 for less . The MK 2 just doesn’t cut itin the looks dept , in fact it looks like a different bike altogether . All the best Simon .

  2. cb1 400cc 1990 can you tell me how to check engine oil level exactly dip stick screwed in or screwed out
    best regard

    1. Screwed out, 100%

  3. Issa Abdul razak Avatar
    Issa Abdul razak

    I got problem with my valves,I just replaced new engine head .but how to set the timing gears

  4. Simon Haddock Avatar
    Simon Haddock

    I own two CB1’s both manufactured in 1989 . these are the MK 1 models which were also produced for 1990. The MK2 series was produced for the USA / Canadian market . Subtle differences for the two bikes . The alloy billet for the MK1 , pillion footrests not steel like the MK 2 . Stainless steel exhaust system for the MK1 was replaced by a mild steel all black system, black plastic headlight , reflectors on the front forks MK2 …Total production 22.000 world wide . 1989 -10.000-1990-8.000 – (MK2 -1991 -4.000- for the USA/ Canadian market) I have been in contact with Honda Japan Hammatsu via their messenger service and talked with a very helpful Japanese lady who spoke English . She confirmed the details and she sent me ( In Japanese ) the total production figures for every Honda CB1 -400 made in Japan and I have had the info translated into English . Bikes with the KM clocks were made for JDM and some other Pacific rim countries. ( JDM =Japanese Domestic Market). Some found their way to Australia and a few went to Hong Kong the Hong Kong bikes will have mph clocks like one of mine . I have two bikes from the same monthly production run in 1989. Rumour has it that in 1989 Honda tested the waters in Japan with 500 CB1’s with the CBRR 400 engine prior to changes they made with the gearing …For reference the 3rd gear on the CB1 is the Ist gear on the CBRR 400 . They are very sought after , I have contacted the DVLA and as of summer 2022 there are only 57 CB1’s reg for the road – 7 are the MK1 1989 JDM models and the remainder are the MK2 version …That doesn’t mean there aren’t more, possibly on sorn waiting for rebuilds . resto’s or just sitting around in garages… Hope people find this useful ?

  5. Simon Haddock Avatar
    Simon Haddock

    Max power of 57bhp reached at 10.000 rpm – warning don’t bury that needle into the red for any length of time , it could overload the cams and you might get into a situation with valve bounce , meaning it will be reving so high that they hover and can’t actually close because the engine is spining so quickly …These engines were race derivedd so are needing to be used , they perform better when above 6.000 rpm and can easily reach 80mph pretty damn quick . For reference the 3rd gear if used properly can do 0-to 75 in one gear , That was the 400 R’s first gear . all Honda did was a re- gear configeration for road use , so you have a short shift to get to 30 pus in 1st- 2nd all the way up to 50 , then if used like a race bike full on until 75-80 -I’ve done it many times , then with the 4th gear it’s just extra until you reach 5th around that mark you will be hitting max power of 10.000 rpm . 6th gear will be stable at top speed of a max around 118-120 Wrongly stated in the blog as being a different engine as the CB400R , the engines are exactly the same and will have a stamp on the right side of the engine , where the clutch cable sits , pull back the cable and you find NC23E.( all CB1 400 ‘s will have a classifiaction of NC27 that is for the frame and running gear, handle bars etc. The NC23 E denotes the same engine as the CB400R the difference between the engines on both bikes is the gearing , with the R having that very tall 1st gear . Made for racing in Japan’s race series at the time . If you need any more information please feel free to contact me ok .I am in contact with Honda’s headquarters in Hamamastsu in Japan . I have in my possesion the listings. codes, production runs , the amount of bikes made , details of years of production and the list gives me every single Japanese bike manufactured from 1966 until the present day . This for the JDM only ( Japanese Domestic Market) doesn’t include bikes made under the Honda name built in other coutnries .Ths list doesn’t even include the CB1-MK2 variants because all Honda did was ship over the engines from Japan and the rest of the M2 was built in Honda’s USA plant …It was the American arm of the Honda company that decided on not supplying the MK2 with steel exhausts , steel footrest hangers and other bits . mainly to do with cost , they were testing the waters with the US model to see if it would sell and it didn’t do well ( there were only 4000 models built in the US . One reason was the bike cost more to manufacture than the then current ‘Jelly Mould CB600 F’ sales seemed to go to the 600 and not to the 400 as was expected . The world wasn’t ready for a naked ‘cafe racer styled bike at that point , all people wanted was the race look which was all popular in the late 80’s early 90’s …Many despatch riders bought these bike that were either shipped over from Japan or the US by container , I know because I was one of the importers ..haha.

  6. John Rigby Avatar
    John Rigby

    Just bought one its a1990 in need of a little TLC Carbs cleaned and serviced.. After reading this thread I Think it musts be a MK1 as its got alloy rear footrest hangers and a mint full stainless exhaust, Only gave £500 for it too!

    1. Chris Gates Avatar
      Chris Gates

      I just bought a 1989 CB-1 in Cobourg, Ontario (a nice small town just east of Toronto). It (the bike, I mean) has an interesting history. It was bought from a dealer in Michigan in 2007 with only 1440 miles on it. It started and idled well. It still has only 1440 miles on it and has been stored at room temperature virtually all of its life. The fellow I bought it from bought it for his son as an “investment”.

      Now I have to get it running. The tank was emptied but not the carbs. The previous owner let the local Honda car dealership keep it in the showroom “as a conversation piece”. He routinely turned the engine over.

      So, here’s what I think I need to do to get it running and certified for the road. 1) clean the carbs; 2) replace all fluids (coolant, oil, filter and brake fluid); 3) replace both tires as the 35 year-old ones seem quite brittle.

      What else am I missing?

      1. My advice would be to get it started before buying tyres etc.
        Check the oil level, replace the spark plugs, check the air filter is still intact and servicable, fresh petrol and clean the carbs if there gummed up.

        If it runs ok with no nasty knocks, smoke (a bit from dirty fuel etc would be normal) or other surprises then go ahead with the rest.

        The engines are fairly reliable so it’s unlikely to have any problems other then those caused by being in storage for so long.

        Other things your likely to need to replace would be:
        Brake hoses (if there the original rubber ones)
        Spark plugs
        Air filter
        Oil filter
        Grease for nut’s, bolts, spindles and other lubrication points
        Also budget for a carb rebuild kit and possibly caliper rebuild kits (if needed)
        And possible cables (throttle and clutch) although these can often be freed up with oiling

        As you mentioned it would be best to change the tyres as they deteriorate over time and are likely to have flat spots if it’s been sat on the tyres for years.
        Good luck 🙂

        1. Simon Haddock Avatar
          Simon Haddock

          Maybe one other thing you might want to do is change the coolant in the radiator , certainly wouldn’t hurt , Air filter is a must and one thing check to make sure sure that fuel pump is working well and quiet . If you hear any loud ticking it’s on it’s way out . Try to buy a Mitsubushi original as the cheap chinese copies are useless. Wiring can get brittle over the many years as it’s been sitting around , especially in a warm envirioment . Is the bike a USA / Canadian model ? – I would think it is a MK 2 version with black steel exhaust and metal foot hangers , still has the same engine . It will have a stamp just behind the engine casing on the right side of the bike . This will say NC23 , which is the model Honda used with the engine from the 400 RR. The NC 27 bike used different gearing than the sports bike with a very quick 1st gear , almost reduntant , quick shift into 2nd get into 3rd and you’ll see where the demons live !!- With 55-57 bhp these bikes fly . They hate sitting around , so the best thing you can do is ride , you will be rewarded with a very happy bike.

          1. Chris Gates Avatar
            Chris Gates

            Mt thanks to both of you! I can’t wait for this dreary Canadian winter to be over!

      2. Simon Haddock Avatar
        Simon Haddock

        Yeah over here in the UK we are having very frequent storms with pretty cold winds ( not the best weather for riding of any sort ) – Good time to get everything checked and prepped for the spring. Hope the bike doesn’t need too much doing to get it all working well . LIke I said in a previous post ‘you will be rewarded with a fine , powerful , light weight machine , that can do the miles and is suprisingly comfortable as well’ . One last thing – the engine because it run’s the Cam Gear System’ should be incredibly quiet even on start up ( don’t use much choke better to warm the float bowls with a hairdrier in colder months -warm fuel much easier to ignite rather than cold ) , if there’s any hint of ‘tapping’ then it could be prudent to check the valves and have everything ‘set’. One of my CB1’s did indeed ‘tap’ quiet loudly on start up and after getting everything set up the noise went away . The bikes don’t use any oil and with regular checking ( dip stick ‘resting ‘ never screwed in) will give you the actual level and this should be done after a ride , leave it 10 mins then check the level this is the optimum level you’ll get . Never cold ok …Sounds weird eh . Good luck for 2024 and have fun .

  7. Simon Haddock Avatar
    Simon Haddock

    You my friend are one lucky dude . As long as the engine spins freely and with no nasty rattles you have got a good un .
    Many parts for the CB1 are interchangable with other Hondas from the late 80’s through to the mid 90’s , electrics especially .
    Plastics are very rare so hopefully yours are all good . Rear plastic cowling is easy to take off but be wary with overtightenng when puting back on, the lugs can snap quite easily . Chain and sprocket, set best to use what Honda used back when new which is a RK Takasago kit . Expensive but so worth it – Tyres your choice but go for good ones , these bikes handle so well and they perform with good quality ‘boot’s . Rear shock could be ok and if not a good replacement is a YSS one .
    Back in October 2021 Classic Motircycle Mechanics ran a full 5 page article on the bike , worth checking out if you can …Well at least I know where 4 of these beauties are right now . Hope you have fun getting her all ready for the road . Colour for that model should be either red , deep blue , black , slate grey …See you .

    1. Sean Hallett Avatar
      Sean Hallett

      Hi, I very recently bought a CB-1 from Torbay Motorcycles in Newton Abbot in red and I believe it may be a bike that you previously owned, I’d read this thread and realised you’re local to South Devon and I actually asked Mark in the showroom and he confirmed it was yourself, I actually worked in the motorcycle trade myself many years ago at William Croft in Paignton, I was in the parts and accessories side of things.
      I did of course ride bikes back then but I haven’t done for over 30 years and I’ve recently returned this year to biking but purely as a leisure pursuit, I decided to do a refresher course as it’s been so long since I’d ridden, I’m still finding my feet, some things are still second nature others not so much, the bike is actually the largest(engine size)I’ve owned, I did have a Suzuki GT380 years ago but I mostly rode 100-200s.
      I am pleased with the bike but the idle speed seems too high at around 1700rpm, I’ve since found out it should be more like 1300, the bike is still under the 3 months guarantee and I may ask Torbay to adjust it but if it’s a very simple job would you be able to advise how to do it, obviously I don’t want to get involved too much as apart from the high idle speed it runs well, although I’m finding the gear change is not the slickest I’ve ever used but it could be me still not used to the bike. Anyway many thanks in advance if you’re able to help.
      Sean Hallett

      1. Simon Haddock Avatar
        Simon Haddock

        Hi there yep that would be the bike I traded in back in the summer of 2023 . I can garantee that all the work that was needed to be done was completed by TBM’s – All the valves were checked , new fuel pump , new carbs , tyres and I made sure that it was as clean as it could be .
        The idle wheel is just under the tank on the left side and is very easy to regulate the idle speed.

        Make sure you get the engine up to temp , you can feel the engine casing’s for warmth . Left turn to reduce , right turn to increase . The idle speed should be around 11.000 or just above . If you have any problems I’m sure TBM’s will help if needed.

        These bikes are bullit proof and so well built , you really shouldn’t get any problems . Hope this helps .

      2. Simon Haddock Avatar
        Simon Haddock

        Ref the gearbox , they are sometimes a bit crunchy , some are some aren’t . Best bet for riding is to ‘quick shift ‘ Ist very short , sometimes I use 2nd to get off on the flat – once in 3rd the bike is happy and if just wanting to ‘pootle in town best keep the bike in 2rd- 4th don’t worry about changing up any more – These bikes are high reving , don’t be put off with accelerating hard they love it when out on the open road . They are very fast , there is a demon that lives above 5000 rpm !!

        Cleaning products vary in usefulness and cost …

        I use silicone spray for the chain , first to clean maybe with parafin or similar and then spray a light coating on the revolving wheel whilst on the main stand, you could use an old tooth brush to work the silicone in after spraying ( silicone spray is great at keeping water out and as it’s not oil based, is kind to the roller bearings in the chain , plus you won’t get that gunge which builds up with chain lube and turns it’s self into a grinding paste ! . WD 40 is always useful for the engine casings and to clean the stainless steel exhaust -best not to use on electric cables and such like , silicone will do .( Trago Mills sell a good slicone product and not expensive) A little squirt inside the the end of the pipe in the winter , keeps out any water ingress.

        Basically after every ride I clean all my bikes , only a ten min job and worth it if only for peace of mind . Like my gran used to say ” You clean to keep it clean , not because it’s dirty ” !

        I never have ever used water to clean any bike , especially a power hose , lethal, get’s in all the electrics and you’ll never dry it out .

        When very cold I use a small hairdryer to warm up the area where the carbs are , helps with starting ( easier to start with warm fuel rather than freezing cold petrol ) only in the winter months . You shouldn’t have to put the battery on an optimiser it’s pretty new and will hold it’s charge well …

        As the bike is quite immaculate , all these jobs should be pretty easy to keep up with . I am very particular about looking after my machines , some say almost to the point of some OCD haha.

        I still have the two remaining bikes one is a ‘donor’ bike in case anything goes wrong and a lovely low mileage blue CB1 which spent it’s life in Hong Kong …plus a very cool Yamaha TRX 850.

        NB – You bought well and from a good shop , Marcus is a decent guy who knows his stuff and has served me well over the years . I wish there were more shops like his right now …

        Good luck and am pleased you like the bike , you’ve got a good un…Plus they are getting very rare in this condition . Oh and make sure you use high grade fuel E5 -97 99 octaine rating . I’m sure it would be ok with E10 but to be safe go for the E5( ethanol is a killer and has to be used up otherwise you’ll get ‘seperation with water and petrol) – See you


        1. Sean Hallett Avatar
          Sean Hallett

          Hi Simon, thanks once again for all the advice, I am keen to keep the bike in good condition especially as it is already so good and amazing for an 89, I have so far been taking it out only when it’s dry although as we know it’s hard to choose a dry day at the moment, I didn’t want to mothball it through the winter as for one thing I don’t want my newly refreshed skills to fade, and as you say the battery spins it over very easily, I’m still taking it quite easy although I’ve found out on the A380 last week that engine just wants to go, also as you’ve said I’ve been pleased with how flexible it is pootling around town and I noticed there’s no problem with pulling away in 2nd gear on the flat.
          Silicone spray is something I hadn’t thought of for the chain but I can see it makes sense, I know some of the lubes are so sticky that all sorts of grit will just stay put.
          I agree with you about the power washing being a bad idea and I’ll be looking for some sort of waterless cleaner.
          You must be a real enthusiast for these if you’re hanging on to your other two, and Mark had mentioned you’d got the TRX850, I’m sure I saw they had another one in there when I collected the bike in early December, it’s a really interesting place and they seem to be real enthusiasts for a certain era of bikes and for imports too.
          I’ll certainly be only using E5 in it, I’m the same with every vehicle I own.
          All the best for now.

        2. Sean Hallett Avatar
          Sean Hallett

          Hi Simon,
          Further to our previous conversation regarding the red CB-1 which belonged to you and which I bought from Torbay Motorcycles in December 23, I thought I’d get in touch with you to let you know I’ve decided to sell the bike or possibly part exchange just in case you wanted the opportunity to buy it, I’ve really enjoyed the bike but now having returned to biking after 30 years or so I’m like a kid in a sweet shop and want to sample as many bikes as I can while I’m still able, in particular I’m interested in a Guzzi Breva or Ducati Monster but I’m still keen to test ride lots of others to see what I might go for next, unfortunately both my finances and space are tight so I’m not in a position to have more than one at a time, I did actually ask Mark at Torbay if they might be interested in buying it back but as you probably know they’ve just bought quite a lot of new stock but they might be interested after they’ve sold a few.
          **Phone number removed – WD Admin** As you can imagine I did pay full retail from Torbay but obviously I’m expecting to get less when selling privately, so if you’re interested just let me know.

          1. Simon Haddock Avatar
            Simon Haddock

            Thanks for the offer but have three machines in the garage and to be honest with you , I don’t ride them as much as I should .
            There is quite a market for the CB1’s right now especially in the condition yours is in . You could try selling it on Car and Classic ‘ on line that’s where all the good condition bikes from the 80’s/90’s are for sale .
            Mainstream bike dealers like Bridge would not be interested but I do know that ‘Speed Motorcycles’ in Marsh Barton could be good for a trade in .

            Check out their site all bikes are listed and they do sell any type of machine …You won’t have a problem with finding the 400 a new home .Perfect machine for a newly qualified rider or ‘born again type – Yep ‘Speed’ I’m sure they’ll consider it .

            – I’ll stick my neck out and say approx £2,200-£2000 for a trade in or hold out for current value of £2.995 on Car and Classic .

            Good luck , all it takes is that one person who’s been looking for that particular bike or someone who wants to get into the retro scene without the vast expense of a new bike …See you .

          2. Simon Haddock Avatar
            Simon Haddock

            Hi there .
            Ref the clutch and gearbox .
            When the bike’s cold the clutch can be a bit stiff with selecting gears . Best bet is to warm the engine for at least a good 5-10 mins before you take off . I’ve never had any issues but did learn a long time ago that these bikes do like a bit of TLC.
            The only time you would have to consider any clutch replacement with low mileage is if the bike has been ‘wheeled’ for any length of time .
            Considering how the bike has been looked after for 35 years I’m doubtful a new clutch is needed.

            Honda around that time did produce ‘crunchy’ gearboxes and this always showed up when the bikes were started cold . I bet you’ll find it quite different during the summer months . The only way of determining if the clutch is worn badly is by ‘slipping’ under acceleration when it will feel like an elastic band trying to catch up with it’self …( It’s not a big job to replace really )
            These engines were tried and tested in the race version of the bike with the 400 RR, so are pretty strong overall …Just let it idle until the engine get’s up to temp . And I don’t mean the water temp on the gage , I mean the oil temp inside the engine. 5 mins should do it fine …

  8. Sean Hallett Avatar
    Sean Hallett

    Hi Simon, thanks so much for the info, that idle adjustment seems really simple and straightforward, I did have one of the invoices from TBM showing the valve clearance check and it said they were spot on, also I had no idea it had new carbs and fuel pump, it’s all great to know and will certainly keep the bike going for many more years, I’ve certainly got the impression of how well built it is and nice and manageable because I’m on the short side, makes a lovely classic 4 cylinder sound as well, I read your previous messages, do you still have the other 2 CB1s I wonder?
    Also I hope you don’t mind me asking but I’m a bit out of touch with modern cleaning products and chain lube, are there particular ones you can recommend?
    Many thanks

  9. Sean Hallett Avatar
    Sean Hallett

    Hi Simon, Many thanks for your helpful reply and suggestions, I’ve been to Speed in Exeter as I was looking at a couple of bikes there before I got the CB-1, the chap I spoke to was friendly and helpful, and I do actually have a look on Car and Classic myself.
    Just a question about the gearbox that I mentioned in a previous message to you, you described them as being a bit crunchy which is a good way of putting it, I spoke to a repair place in Paignton that has a good reputation and he suggested it might be in need of a new clutch, or is it just a characteristic of the box in your opinion seeing as you’ve lots of experience with that bike, I don’t really want to spend out on it if it’s not necessary and I’m trading it in anyway.
    Many thanks

  10. Sean Hallett Avatar
    Sean Hallett

    Hi Simon, yes what you’ve said about the stiff clutch when cold is exactly what I’ve found and I generally let the bike warm up before I set off, I know Honda’s are usually very well developed and give few problems so it’s good to know that it’s unlikely to have a worn clutch in need of replacement, there’s no sign of any slipping at all when I’m riding it.
    Thanks once again for the information and advice.

    1. Simon Haddock Avatar
      Simon Haddock

      No problem ,should all be good –
      Maybe take a ride up to ‘Speed’ in Exeter and then you can show them the lovely condition the Honda is in with ref to a trade in ( if you find what you want ).
      They have a good selection of older bikes , I have bought a couple of bikes from them over the years . One thing with Speed’ is that they don’t do any type of ‘real servicing’ prior to sale or exchange ‘sold as seen’ as they say . Always a bit of a punt … .Just a general PDI which is always a bit of something and nothing !
      – Just checked on their site and there’s a nice looking 2009 Moto Guzzi V1200 Sport going for £4995 so with your bike say for £2000 trade in ? Depends on the budget you’ve given yourself I suppose …I’m sure you’ll find what you want , just takes a bit of time …Happy hunting .

  11. Sean Hallett Avatar
    Sean Hallett

    That’s actually a good suggestion for me to ride up so they’ll know exactly what the CB-1 is like, I’ve had a look at their stock and there’s a few I like the look of including that Guzzi, I’ll have a word with myself about the necessity to have a litre plus bike in my life. All the best.

    1. Simon Haddock Avatar
      Simon Haddock

      This week is going to be ok apparently . I went up to Speed today , good choice of machines …I took a fancy to one of my old bikes an immaculate Yamaha FZR 1000 from 1988…Hmmm. Nice but can’t justify another bike .

  12. Simon Haddock Avatar
    Simon Haddock

    Shame the weather’s pretty rubbish right now , you’ll have to wait for some dry weather eh !…
    I reckon they’ll do a deal …good luck .

  13. Sean Hallett Avatar
    Sean Hallett

    I know, it’s pretty annoying and a day where it doesn’t rain seems to be a rare thing, roll on spring and summer!

  14. Richard Stein Avatar
    Richard Stein

    Just about to take delivery of a CB1. Clocks are in KM so does that mean MK1? Took a ride on it briefly, it is pretty rapid for what it is. Old school good fun. Showing 28000kms which if genuine is pretty low for 1989. Will do an oil change, 10w40 Castrol fully synthetic unless anyone has a better suggestion. Happy riding…

    1. Simon Haddock Avatar
      Simon Haddock

      All MK1’s had stainless steel exhausts , alloy billet passenger foot pegs. Check the right side of the engine casing ,just behind the clutch cable -should read NC 23 which is correct the bike’s code is NC27 .KM clocks would be the Japanese only machine . Later MK2’s had MPH clocks for Canada and USA. Engines were all the same although rumour has it that 500 MK1’s were sent to Japanese dealers in early 1989 to test the market and they are meant to have the Aero RR 400 engine with the very tall 1st gear and slightly more BHP . Standard engines put out 57 BHP with a very short 1st gear …3rd gear is where the power is and don’t be afraid to use the rev’s these bikes love it …Should do around 119 to 120 MPH top speed with loads of torque if you keep the revs above 4000 plus. Fast little bikes .

      1. Radio Rich Avatar
        Radio Rich

        Thank you. I take delivery on Friday. Exhaust is stainless, will take a closer look when I get it. Can’t wait to enjoy myself on this little monster. Will post again when I get it

        1. Simon Haddock Avatar
          Simon Haddock

          Keep me posted on progress ok …Love these bikes , if you get a good one it’s worth keeping . Remember no cam chain to worry about ‘Gear Driven Cam’ magical piece of engineering no adjustment needed . Back in the day despatch riders in London bought many CB1’s part of our ‘ Grey Import Boom …They would ride them up to crazy mileage’s , just with oil and filter changes. If the bike’s done around 20.000 miles probably worth having the valves checked , if it’s running smoothly with no glitches I’m sure all is good . Once checked you probably won’t ever have to do it again . Good idea to change the coolant as well , especially if it’s been standing for any time . Air filter is simple to replace always good practice to change as well – Chain and sprocket set has to be the correct kit to get max power out of the bike -Have fun ok . …

  15. Radio Rich Avatar
    Radio Rich

    NC23E On the engine casing and has everything you describe

  16. Simon Haddock Avatar
    Simon Haddock

    Yep great ,do you have the stainless exhaust and alloy passenger hangers…?

    is it either Red , Dark Blue, Black with CB1 embossed on the tank ?

    If it has black steel passenger hangers and black steel exhaust then it’s the US/ Canadian export model they all had MPH clocks . These are the MK 2 version. Same engine with 55/57 bhp-
    Some changed the JDM km clocks for mph versions and some were re calibrated with a gear wheel on the km clocks to read in mph …Glad you’ve got the bike now , check the fuel pump for any strange sounds when you go to start up , if the bikes been standing for some time the stale fuel could gunge up and a fuel filter is always a good replacement . They should fire up pretty quick . If it’s cold try blowing hot air around the carbs with an old hairdryer just to warm the cold fuel , it will help with starting . Best bet is to run the engine on idle up to temp , not the water temp but the oil temp – 5 mins should be enough –
    Just let it idle .After that the engine is prepped ready to go (after all these engines were built for racing , it will thank you for it )

    -Obviously if where you live is hot and dry then it should be a much easier start …The bikes run perfectly in misty cooler temps , loads of pure clean air to suck in and then watch her go…Have fun .

  17. Radio Rich Avatar
    Radio Rich

    It has a stainless exhaust and alloy passenger hangers. The clocks are in KMS. It is a very light blue colour (⛎ this colour) with CB1 embossed on the tank. Did 100 miles on it yesterday, incredibly quick and love the music it plays!!!!! Give me your email address and I’ll send you some pics.

    1. Simon Haddock Avatar
      Simon Haddock

      Not sure if this will work ok , this site seemingly doesn’t allow emails to be printed . Here goes .

      ** Removed by WD admin **

    2. Simon Haddock Avatar
      Simon Haddock

      NB – Forgot to congratulate you on getting one of the ‘JDM’ models , very cool indeed . They are pretty rare now , especially in good condition.

      Survivor bikes . Oh yes always try to use high octane fuel , they seem to run better …Not sure about the email , would be good to swap pics.

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