Honda-SOHC

Meanwhile whilst we await Murf's photos here's the sound of a CBX with 6 into 6 pipes. Turn the volume to 11 and enjoy......
https://youtu.be/UH4ZIsWy4SE?si=ZTZrzMlZof_WnpbN
It does sound a bit like a Laverda Jota👍

A few photos of the beast would be nice please Murf😎👍

Whilst I was ordering parts for the NC30 the other day from the guru of NC30’s, Rick Oliver he mentioned about his old 400/4 and how he made it into a 460cc Cafe Racer. He sent some photos over and gave me permission to post them on here.
His bike went through a number of iterations over the years and in its final form it was fitted with reverse comstars, a Mead Speed fuel tank, CB250RS front mudguard, a Yoshi 460 kit and exhaust and a home made seat. I'm not sure about the rear sets but a very nice bike. He doesn't have it now which is a shame.

That's what I was told John, the rear spring will easily bottom out.  Same with the front, the standard springs are based on a 10 stone Japanese rider, not a 12 stone Englishman! I've already bought a set of uprated front springs from Rick Oliver to fit when I get the fork bottoms back.

I would rather take an engine out of a frame then to do a starter clutch!
Getting the engine out (and back) on a 400/4 is pretty straightforward.
Remove the seat, side panels and tank together with the handlebars, rear brake pedal and footrest assembly, battery and the complete exhaust system (in fact anything sticking out of the right hand side but not the rear shock). Take off the chrome points cover because it will likely get dented and remove any wiring loom connectors to the engine (alternator, starter motor & points)
Remove the rear engine to frame bracket (it has the main earth lead attached to the through bolt) and the engine to frame bolt at the front of the engine on the r/h side and on the lower crankcase. Remove the sump pan and take off the oil pick up strainer (push on fit) and lay the bike over on its right hand side preferably onto something soft with a bit of give. Proceed to remove the front engine to frame brackets and the left side lower crankcase to frame bolt. You can then lift the frame off the engine that will remain on the floor.
Replacement in the words of Mr Haynes is a reversal of the removal procedure!
It sounds like a lot of work but in reality it isn't but I would recommend enlisting a helper when it comes to laying the bike down and lifting the frame away from the engine.
You can access the starter clutch from below if you take the sump and off side covers off and without removing the engine from the frame but it is very hard work trying to work below an engine even on a bike lift.

An update on the NC30.

First the good news, the wheels and various other parts are currently undergoing blasting and powder coating. I’m collecting all the BZP and yellow passivated parts tomorrow (one week turnaround and £60 for everything in the photo).

I took the frame, bare swing arm and footrest hangers etc for vapour blasting to R D Cox in Reading. Doug advised me not to vapour blast the frame as it is anodised and a vapour blast finish wouldn’t look good on the side beams. He told me to use steel wheel cleaner and a stiff brush. Looking around I came across an alloy wheel cleaner made by Bilt Hamber so ordered some. It was excellent; it cleaned up the castings and the beams really well. It was so good all I needed to do was to use some solvol on the two side beams and they are like new!

And the bad news, I thought the engine was all good and wouldn’t need anything more than a good clean and service. Checking the valve clearances revealed one missing valve shim, oh dear. Looking as best I could down the drive gear tunnel with a torch I couldn’t see anything. The thought of a shim floating around inside the engine fills me with dread so it was off with the sump to hopefully find the shim sitting in there. No luck although it did give me a change to clean out the sump pan. When I took the oil pick up strainer off I found a chewed up piece of metal although not a shim lodged inside (see photo). I have no idea what it is/was. I looked inside the engine from underneath with a torch but no sign of a shim.

Next I removed the cams and the cam gear drive from the front cylinders where the shim was missing from to check if it had lodged in there; it was clear so all that went back in...slowly and keeping an eye on the valve timing marks.  I did notice though some score marks to the underside of the casing looking down from the now empty cam gear tunnel (photo). Something has defiantly been floating around the engine at some point doing some minor damage.

Next up will be to remove the engine side covers to see if the shim is in the clutch area or the alternator. If it’s not there I can only assume it may have been flushed out during an oil change at some point in its past. I know from speaking with Rick Oliver the checking of valve clearances on the front two cylinders is notoriously difficult unless the two radiators are removed first and even then it’s so tricky to change the shims a lot of these engines never get checked. Maybe they were checked at some point and the shim was not properly placed and was spat out when the engine was started.

I have to say though it is a real jewel of a bike, build quality is immense.

Didn't know you had a CBX as well Murf. Jealous now. Keep promising myself that if I get some money together someday and it's not earmarked for the house I'll treat myself to a red CBX. Not the prolink type though, never really liked those. Fancy a CBX550 as well.

Exactly the same thoughts over here Ken. The red CBX was (and still is) so cool. The 550F2 CBX was the same but a lot cheaper although I still couldn't afford one when they were new!

I called Brooks Suspension last week Johnny to enquire about them rebuilding the rear shock of the NC30 (apparentley its not worth doing they said, I'd be wasting my money refurbing a shock that wasn't very good when it was new! They are trying to steer me in the Nitron £700+ route, err.....no!). I asked about replating the front stanctions and they quoted £200 but it would be an 8 week turnaround. They don't do them there, they are sent out although they didn't say to who (Dynasurf???).
I stuck with Philpots in the end as their work is really good quality (I've used them five times before) and I was able to drop them off myself. Price is £330 for both and includes posting back to me when completed. Turnaround time is 4 weeks but likely much sooner.