HONDA CB400 FOUR

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Yep, been hand painted as well:blast

Right, an update.

The carbs were in bits, but fairly clean. Spent about 2 hours assembling them, stuck them on, some fresh fuel and........it started!

Sounds OK ish. Got 4 cylinders, 6 gears, clutch feels OK, all in all considering it hasn't ran in a few years OK.

Knocks a bit at low RPM, phoned a mate who grew up on these, "they all do that sir"...Apparently they were nicknamed the coffee grinder....

So, looked at the charging system as it wasn't working, that'll be because the recifier is missing :augie:augie

Front brake stuck on, lever all flappy.....removed master cylinder, free off seized piston, re-fit and bleed, good firm pressure! and it doesn't leak! remove front caliper, pads stuck in, remove, free off, it has a new disc and pads on it... Bled front brake through again, and....it works!

So, back to that engine. The original plan was to get it running, MOT, use it for a bit then strip, but...

The engine is out, head off, all looks OK! Primary chain is absolutely knackered (that'll be the knock then :D) but the pistons/bearings etc look OK. Those pistons are SO cute....:D:D

I am going to get the crank cases/barrels/head vapour blasted and painted in the original silver, and have the frame dipped and painted.

Also noticed it must have had a new r/h fork leg quite recently?

I'll keep a diary on here.
 
Had an F2

One of the last - T reg - in Parakeet Yellow.

Rode it for 6 years/45000 miles - a grin a minute!

(EDIT - just realised how long this post is - boy do I regret selling this bike in 1994!)

Tips for the rebuild:-

Camchain is supposed to be endless = crankshaft out to change. IIRC a split version became available for the lazy!
The tensioner is manually set (bolt protruding from crankcase above oil filter - if overtightened - helicoil required!) The tensioner is spring loaded - there was a tip in the Clymer manual about where to set the crank to gain best tension (15 deg past TDC???) - release the bolt, tensioner self-adjusts, then retighten bolt to fix. Chain would stretch if not regularly retensioned. Also tensioner blade wears out so replace when head is off.

Front brake - grease the swinging-arm pivot regularly; they seize. I put a 0.5p coin behind the front brake lever to reduce the free play/increase the reach - being 6' 6" meant I didn't really fit the bike too well!

Coils - terrible in rain - I remember suddenly riding a 200-2 on the M1 at night whilst overtaking a truck. God knows how, but he realised what was happening immediately (maybe he owned one!) and let me cross to the hard shoulder! Lots of silicon rubber sealing/WD40 stopped it shorting out (eventually).

Swing arm bearings - made of compressed paper. I fitted a Dresda box section arm with taper roller bearings (pukka cafe racer, me!). Fit new OE if you can; not a big job but makes a difference to handling.

Oil change EVERY 1500 miles and filter every 3000! Gearbox and revs chew it up.


Mine had a Honda 550 Rickman fairing, Bottelin et Demoulin (spelling? - Google them - French endurance team in 80s) clipons, Dunstall rearsets (yes, really - as I am so tall it was like Origami watching me get on the bike, but I was young and flexible then.....), Cibie headlight (literally brilliant, especially with 100W bulb (on a relay)), K&N individual air filters jetted to match, Yoshimura exhaust and electronic ignition. Sweet as anything. The old trick was to stand a 50p on the tank when on the centre stand and redline it and back to idle and the coin remained upright.

Toured France twice (Bol D'Or 1981 at Paul Ricard nd Le Mans 24 Hours in '82, both with "Team Bike" (cheap ferry tickets and a race team too!).

Bought but never fitted - 460cc Yoshimura kit, Dixon Yoshimura gas-flowed head and Yoshimura Road & Track camshaft with race camchain. Sold the 460 kit in the 80s but kept the other bits until I moved to Oz last year. Got >£300 for them on eBay to a guy building a Mocheck Harrier from scratch! He could not believe his luck finding these parts. I even had 2 head gaskets for the 460 kit.

Happy days

A
 
knocking noise is the clutch basket because the carbs are out of balance by a small amount.

or the camchain tensioner isn't working
 
Yep, been hand painted as well:blast

Right, an update.

The carbs were in bits, but fairly clean. Spent about 2 hours assembling them, stuck them on, some fresh fuel and........it started!

Sounds OK ish. Got 4 cylinders, 6 gears, clutch feels OK, all in all considering it hasn't ran in a few years OK.

Knocks a bit at low RPM, phoned a mate who grew up on these, "they all do that sir"...Apparently they were nicknamed the coffee grinder....

So, looked at the charging system as it wasn't working, that'll be because the recifier is missing :augie:augie

Front brake stuck on, lever all flappy.....removed master cylinder, free off seized piston, re-fit and bleed, good firm pressure! and it doesn't leak! remove front caliper, pads stuck in, remove, free off, it has a new disc and pads on it... Bled front brake through again, and....it works!

So, back to that engine. The original plan was to get it running, MOT, use it for a bit then strip, but...

The engine is out, head off, all looks OK! Primary chain is absolutely knackered (that'll be the knock then :D) but the pistons/bearings etc look OK. Those pistons are SO cute....:D:D

I am going to get the crank cases/barrels/head vapour blasted and painted in the original silver, and have the frame dipped and painted.

Also noticed it must have had a new r/h fork leg quite recently?

I'll keep a diary on here.

When you re-assemble it DON'T FORGET TO PUT THE OIL BACK IN :augie
 
OK, so I took a few more pictures so as I would remember where things go when I come round to putting it together then one thing led to another, now its stripped.

Frame is going to be powder coated, including swing arm/centre stand.

Engine is in bits at work. Cases are with the vapour blasters at the moment.

Let the spending begin......
 

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when you re-assemble it do not forget the washers on the front bottom engine mounting bolts, if you forget them the crankcases crack and the oil falls on the floor
 
when you re-assemble it do not forget the washers on the front bottom engine mounting bolts, if you forget them the crankcases crack and the oil falls on the floor

:thumb2 thanks for that, there wasn't any there and the r/h bolt was missing.....
 
typical problems were siezed brake pistons, they corroded so need taking out and cleaning well every 10-20k miles depending on usage. quite a lot of mechanical noise at low revs, mostly cam chain, but it is a ratly engine, but this goes away at higher revs.
 
VIN PLATE QUESTION

I have a question about the VIN plate on the Honda.

The one thats on there has a few scrapes/bends/blemishes on it so i decided to replace it with a newie.

David Silver says the OE ones are NLA so i did a hunt on the net and came up with these people.
http://www.vin-plate.co.uk/

Bingo! for a tenner they have the plate I need (Honda 2) but it will come blank. I can stamp the VIN onto it but the other details (model, capacity etc) on the original plate are not stamped but sort of painted black.

Any ideas how I can reproduce this?

:thumb
 
400/4

Had a F1 1976 with the rear footrests on the swingarm - if you had a passenger they hed to have strong legs to aid damping - great bike


Steve :thumb2
 
find a local graphics place /sign shop with a digital printer and ask them to fit the information into the relevant space and print onto a clear self adhesive film.
if they/ you get really clever ...you could have the print made to the exact size / shape as the vin plate - print in the relevant area's then apply over the whole of the plate,that way it wouldn't be so obvious . IYKWIM !!

another way could be to buy some 'waterslide' decal sheet from a craft shop / internet and print your own details etc. a coat of clear lacquer would protect it.

these maybe able to help with the waterslide stuff .. www.fox-transfers.co.uk
 
I have had 6 of them over the years, used to have a lovley F2 when I was a sqaddie in Germany, used to come back to the uk with no proper luggage, just an army suitcase and a kit bag strapped on the back
 
I have had 6 of them over the years, used to have a lovley F2 when I was a sqaddie in Germany, used to come back to the uk with no proper luggage, just an army suitcase and a kit bag strapped on the back
 
I would have a good think before I powder coated the frame.

All the top restorers wouldn't dream of doing that.

It looks naff - nothing like the original paint

Lots of stuff in all the modern classic mags about this

an NO stainless crap either !

I remember motorcycle services in St Albans selling these to the Wheelspin dispatch guys for £699.

1500 mile service every week, all had over 45k on the clock within a year
 
I would have a good think before I powder coated the frame.

All the top restorers wouldn't dream of doing that.

It looks naff - nothing like the original paint

Lots of stuff in all the modern classic mags about this

an NO stainless crap either !

I remember motorcycle services in St Albans selling these to the Wheelspin dispatch guys for £699.

1500 mile service every week, all had over 45k on the clock within a year

Do you know I have been wrestling with myself over this for the last couple of weeks. One of the main reasons I decided to go for powder coat is its durability. Also the bike is not going to be a show bike, just a very clean useable classic. Now you have me thinking again:blast
 
Yes, dont forget its your bike - do what you like.

I dont like stove enamel or powder coating for esthetic reasons and because they mess up threads and earths.

I prefer to see an original worn finsh - a patina of age so to speak.

Just stop it getting worse with regular protection - oily rag or 'maintenance spray'

Also, if the frame is too shiney, you wont be happy with the rest :blast
 
Hello Smudger - I am Alan, up the road from you in Swindon.

I was browsing the web for CB400 Four related articles and found you :beerjug:

I thought that you might be interested in my story on my 400/4s and perhaps I can offer you some local help if you are interested.

Years back, in 1976 when I was 16, my older brother passed his bike test and PX'd his Honda CB125S for a brand spanking new red Honda 400 Four F1. I loved his bike and was soooooooo jealous as I was still a couple of years away from getting a licence. He used to take me out on the back and I was blown away by the little turbine. What an engine - he would wring its neck through the gears and it seemed like it had twelve gear changes.

Anyway, he sold it after a year or so and bought a completely boring CX500. Me? I fell for British bikes and ended up buying a very non standard 1960 Matchless G80 500 single, which I still own (my pride and joy).

The years went by and the little Honda was still in the back of my mind. Until... When Friends Reunited kicked off in the early 2000s I decided to organise some school reunions. At the second one, one of my old classmates pulled me to one side and said "Alan! Do you remember that your brother had a red 400 Four? Well I always wanted that bike, so with my first paycheck after I joined the RAF when I was 18 I bought one just like his. I rode it on and off for ten years or so. It's been sat in my garage for the last twelve years. I'm not going to ride it again. If you want it, it's yours!"

Hmmm. Having a shed load of bikes and a few cars in bits at the time I didn't think that this would go down too well with my good lady, so I let it rest.

I got a phone call last summer from my old classmate. "Alan - I'm selling up and moving to France for a new job. You know I promised you the 400? Well if you want it you are going to have to come and get it before the end of the month." Bugger. Double bugger. Another bike in my collection would not be a welcome move at this point in time. "Ah, ok Barry. Erm, how much do you want for it?" "Oh, I don't know. I will have a look and see how much they are going for."

My heart sank. I knew full well that reasonable examples are selling on eBay for over two grand. I wanted this bike SO much. That was way out of my price range and would be divorce inducing.

The following week I got another phone call. "Hello - about the Honda - I have investigated. But to be honest Alan, you are a very old friend of mine. I know that you will look after the bike and if you promise to take me out on the back of it when it is going again I will let you have it for £200."

Jaw hit floor. Stomach went over. "Are you sure Barry? That doesn't sound like much?" "No, it's fine. When can you pick it up?" Needless to say the hire van was booked for the very next weekend.

A knock on the door and there was Barry. "I will have to dig it out, it is buried at the back of the garage." The accumulated rubbish was removed and the covers came off. My god. A totally original red 400 Four in very good condition. The same as my brothers. I did a double take. "Err Barry. Your garage is very dry, isn't it?" I looked at the speedo and nearly fell over. 11,000 genuine miles from new. Very little rust, just grime from years and years of storage.

"Oh, by the way" said Barry. "Over here is another one in bits. A mate gave it to me for spares yonks ago. You can take that away as well." Stunned. Speechless. Two little Hondas headed back to Wiltshire :bounce1

I have taken my time with the complete one and spent a fair amount on it. It is nearly finished but I didn't want to ruin the originality so have replaced the cruddy bits - Campbell rusty silencer, ripped seat cover, nasty OEM rear shocks. Along with a new front mudguard, new points/plugs, HT leads, carb kits, cables, front caliper/brake master cylinder kit/hoses, full service, new tubes and Avon Roadriders. Plus loads of Solvol, T-Cut and polish. It is looking pretty sweet and should be back on the road in the next couple of weeks. I can't wait.

Apologies for the long first post. I hope that my tale is of interest. Sometimes these things are meant to be.

If you need any help Smudger, then drop me a PM. I have technical reference stuff, links and have trawled the web for tips and advice over the last nine months. Perhaps we could meet up and compare notes if you would like.

PS - a footnote. My brother came to visit last autumn. I hadn't told him about the 400. After lunch I asked him to come out to the garage to 'see my new bike'. The reaction was amazing. He was completely gobsmacked, I thought he was going to cry! "This is incredible" he said. "You have taken me back to when I was 18." He couldn't stop stroking it. I guess that some bikes just have that effect, eh?
 
Lucky Alan :bow we need some pictures mate :D
 
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