Honda-SOHC

Place a bit of heat shrink on the long tail of the spring otherwise it will mark the paint on the frame. Honda used a piece of very tight fitting, thick walled rubber type material. I had to use a heat gun to make it go pliable to remove it before getting the spring re-zinc plated.

Don't mention supermarket fuel! My long running saga with trying to tune the 400/4 following it's rebuild took a turn for the worse after I used fuel bought from a supermarket. It had been running reasonably OK with just a bit of fine tuning required but I had run out of fuel I'd bought from my local BP garage. The OT was going shopping so I asked her if she pick me up a gallon of fuel with the sea bass and spuds and handed her my empty jerry can. She duly returned with fuel and into my empty tank it went and I resumed the tuning. The bike ran worse then ever, spitting back, running rough tickover up and down followed by the carbs going all incontinent again and resulting in yet another strip down. When I removed the float bowls I found water mixed with the fuel! I emptied the remaining fuel into the MX5 (other lesser fun sportscars are available). This happened about two weeks ago and I shall never put supermarket fuel in any motorcycle again although I'll fill a car fuel tank with it, the Mazda didn't mind going teetotal for a few days!

John,
There is an oil bath of sorts in the 400 head directly below the camshaft. From memory I think only the cam lobes themselves dip into the oil in the bath as the cam spins.
As the oil sprays out of the drillings from the spray bar over the cam it collects in the oil bath to a certain level. When the level is reached the oil runs back down into the engine. Maybe Julie has a photo of the top of the cylinder head to demonstrate the theory?

After leaving school in 1978 I became an apprentice coach trimmer in the London Transport Acton Work train overhaul workshops.  It was all sprung seats, horse hair, leather and hand stitching back then, foam was toxic when burned, not a good idea underground!  I was sent  on a residential course where I learned to make hand stitched saddles for horses (not many of those on the tube!). I ended up making all the box leather brief cases for the officers of the company, they must have cost an absolute fortune as each one took a week to make being all hand made and stitched, I never made one for myself though!  After 6 years I got bored, the company was looking for ex-apprentices to move into the technical offices and I became a design draftsman as I was always good at TD in school and it was my best subject at college.  I had the best job in the world thinking up and designing mechanical equipment all day, and seeing it made and used in the workshops. All the other guys in the office were also in their 20's and 30's and had the same outlook. We used to all go out on Friday's and would meet up sometimes during the weekends, we still meet up on a regular basis now for nights out even though we are well into our 50's. Shame this type of bonding doesn't seem to happen nowdays, people leave the office at the end of the working day and retreat into their own worlds.  Unfortunately CAD came along in the early 90's and ink drawing on film was finished for ever , the whole department was closed down in 94 when it was 'outsourced' . I moved into project engineering which was good but it became boring as it was all office and paperwork based.  I got restless and was offered an opportunity to move onto the Jubilee Line railway extension as a site engineer, hard work but I loved it, I met many people who have remained great friends ever since.
In 2001 I became a project manager and have stayed with it ever since having manged some big projects such as extending the tube to Heathrow Terminal 5, rebuilding Stratford stn ready for the Olympics and now upgrading the surface lines on LU with new trains and signalling. I'll be retiring next year once I've got my 40 years of service in and will still be young enough to enjoy my bikes.
As for motorcycles, I had my first Honda SOHC in 1978, it was a 1966 CB160.  I kept it for 2 years before buying a Matchless 250CSR (why, oh why  ). After that it was a CB200 and I px'd it for my first 400/4 in 81 (I've had 5 in total, I must be addicted!). I bought a CR750 Rickman Honda (still got it in boxes), it was a S&S bike although the engine had been changed at some point. Modern bikes followed and I've still got my VFR800 after selling the Blackbird last year.  Other bikes are a Laverda 120 (I rode it to its birthplace in Bregenza following its restoration) and a Morini 350 Sport.  Restoring bikes is my hobby/passion/frustration in equal measure (especially 400/4 carbs!). I raced speedway for 4 years at Wimbledon and Iwade on a 2 valve Jawa 500, marriage saw an end to that little escapade, the subsequent divorce saw the bike being sold along with my restored 400/4, drum kit and the Triumph Spitfire to enable me to hang onto the house (and having to work 3 jobs and doing private coach trimming on MG's to pay the 15% mortgage rate)
After many years of working in cold, damp sheds I finally have a garage with a lathe and a proper bench and bike lift, bliss  .
I stumbled across the SOHC forum a couple of years ago, its been a godsend, great people (and I've even been in touch with MCITD on here who also worked at LU for 20 years) great chatter and advice.  Long may it continue 

Good luck with the rebuild Julie. If you need a new cam or the rockers redressed I can recommend Newman Cams.
Don't touch the carbs!!! 

Newman Cams reprofiled the rockers, £37.50 each. Not cheap but you get what you pay for and they were really helpful.  Their phone number is 01689 857109.
They told me they have a new cam for a 400/4!

Good Luck with the restoration, hide the bills!