Terry

I agree with JZH, the ring is the antenna only, and the ECU has to be instructed to accept the code transmitted from the IP46 chip mounted in the key. I'd be very careful buying an ECU UNLESS it comes with at least one known-to-function chip/key. To program acceptance of a new key, you first need to have an accepted key. I presume Honda will sell you a new ECU plus keys as a set.

Where's the VF400F?

Some more images from the Honda.jp website

The vacuum difference is given in mm Hg, which has a density of 13.6g/mL. Looks like you have oil in your tubes, density of that would be around 0.8g/mL, so 10mm Hg vacuum difference would be 170mm of oil.

Happy to help. For the flapper, the simplest thing to do to disable it is simply yank off the hose at the actuator on the airbox and stick a plug in the hose (apparently a golf tee is just the right size). If you were really keen you could remove the unlabelled hose between the throttle body and the one-way valve and cap the spigot on the TB, and toss the rest in a bin. Personally I left the flapper in operation as I could not tell any difference in performance, it just made more noise at low revs. All I did to my 5G was to remove the PAIR system and put blanking plates on the reed chambers, not for any performance reason, simply to get rid of all the extra plumbing. Whatever you do, make sure any vacuum hoses are either connected to a device or are capped off so you don't get any unexpected air leaks back to the intakes.

Sorry if this is teaching you to suck eggs. The stubs on the airbox are only for securing the hoses and sealing their ends during normal operation; they are just bungs. The vacuum signal comes from the side of the intake ports under the throttle bodies. The pic below is from an eBay listing but shows the #4 hose connection at top right. You may need to lift the TBs up for access, and you will need a LOOONG philips head screwdriver to get to the clamps. Hope that helps.

Well researched post Jkson! When I had my 5th gen I did what I thought was right and dropped the liquid level in the gauges by 10 and 20mm for 3 and 4, which is setting less vacuum in those cylinders. I never thought to do it the other way.

Totally agree with this. I remember my first ride on the 86 VFR and I was suprised at the uneven pulsing at low revs compared to my previous VF bikes with the 360 degree cranks. My 800 was more of the same, and really wasn't happy below 3000 rpm either. By contrast I also have a VTR1000F and that is quite happy at lower revs, so go figure.

I've got the manual for that and there is no code for 6 blinks (nothing for 3, 4 5 or 6). A long blink (1.3 seconds) is equal to a value of 10, and if there is more than one fault then it blinks for the lowest number fault first, then second etc. My guess is you have more than one fault. You could clear the fault register and run the bike and see what new fault occurs. If you started the bike with any sensor disconnected during maintenance then it will record that as a fault. I can give you a link to the manual if you don't have it.

The rated intake vacuum at idle is 200-250mm Hg according to the service manual. I had no difficulties with my SynchPro or the Morgan Carbtune. Out of synch starter valves may give hard starting, stalling or a rough idle.

I'm pretty sure the butterflies are factory set and there is a warning in the service manual to leave them alone.

Yes you certainly can do the SV synch without removing the airbox on the 5th gen bikes, and I did just that on my 99; I think on the 6th gen VFR (02-12) you do have to pull the airbox because the SV's are located in the V rather than on the side. Accessing the SV adjusting screws is a little tricky but I used an open ended spanner for the job, IIRC 7mm was just right.

This is probably just the clutch plates being stuck together having had no use since last year. I'd suggest letting the engine/oil warm up fully first. Then turn off the engine, put the bike in 1st and pull the clutch in, then try rocking the bike back and forth to break the clutch plates loose from each other. When the clutch lever is released, the springs push the clutch pack together, cold oil will keep them stuck together, and is the reason for the usual CLUNK when you drop into first after the starting the bike from cold; what you need is for some oil to get in between each of the friction and steel plates. With the clutch pulled in, the plates should be free to slide over each other but in your case it make take a bit of extra effort to get them to start sliding. Good luck.

What do I win????

Maybe they are the caps for a set of non-standard bar risers? Is the diameter 43mm (to match the fork legs?). The picture below is not exactly the right part but the two caps at the top may be what you have (without the decorative hex nut).