GreginDenver

And you never have to do a valve adjustment on a 6th Gen. Well, actually... you're supposed to do valve adjustments on the 6th Gen but when you find out how technical and intimidating the job is and how much the Honda dealership wants to charge to do it in the shop you'll quickly join the "I've got a 6th Gen with XX,XXX miles on it and I've never done a valve adjustment and it runs just fine" club, and then you'll post here on the forum about how your 6th Gen has XX,XXX miles on it and you've never done a valve adjustment and it runs just fine. Problem solved. (onward to Democratic Socialism and world peace!)

Another thought: Even if it turns out that the issue isn't hydraulic lock I wonder if the current situation might still be a direct result of the accidental fuel bath the cylinders got. If the cylinder walls were stripped of their oil film there might now be so much static friction between the piston rings and the cylinder walls that the starter motor doesn't have enough torque to turn the engine over (the starter motor is getting proper power but is "stalled" by the friction load). It would effectively be a "cold seized-engine" condition. This is just me thinking about the situation while I was running this morning. I think it might be wise to test for this condition by carefully hand-turning the engine (in the proper direction only, of course) just the way you do it during a valve adjustment proceedure. If it feels like the crankshaft cannot be turned with normal/reasonable force (I would assume that every Bandit 400 owner would be familiar with this from having performed valve adjustments, and would be able to judge this correctly) then I'd suggest spraying some engine oil through the spark plug holes into each of the cylinders.

The "click" you're getting from the stater relay sounds like a healthy, full-voltage click. If the starter relay wasn't getting enough voltage to hold it in the engaged position it would probably make a rattling, ragged-sounding noise. If I'm interpreting your short video correctly it shows you pressing the starter button twice and with each press you get a good, solid-sounding click of engagement from the starter relay, is that true? If so, it could be that there's nothing wrong with the starter relay. It would seem that you've checked off these items: Good battery and good starter relay engagement. Maybe there's just something preventing voltage from flowing through the starter windings, like perhaps the starter motor's path-to-ground (negative) wire has come loose? Or maybe there's a problem at the main grounding lug on the engine? But.... it's possible that your situation has nothing to do with the electrical system: "More strange, it's impossible to jump start the bike because as soon as I release the clutch, the bike stops violently (like something mechanical preventing the bike from moving)." This statement is a bit worrying. You mentioned yesterday that you accidentally left the bike's petcock in "prime", I guess it could be possible that one (or more) of the cylinders is full of gasoline and you are experiencing Hydraulic Lock as a result. Just a thought.

Because the Bandit 400 is an older bike there's no computerized ECU to detect lower-than-normal system voltage during cranking and react/compensate by correcting (lengthening) spark plug dwell time to guarantee proper coil saturation before the spark is fired, so as the battery ages and begins to deliver less and less cold-cranking amps you end up with a weaker spark due to lower/incomplete coil saturation. This alone might not create a hard-to-start situation, but combine this with something else like older spark plugs that have developed an incorrect spark gap or HT lines that are less efficient than they were originally, and these additive conditions can give you this sort of result. But that only addresses the electrical side of the coin and as a B4 owner you surely know that those Mikuni BST32SS (or BST33SS) carbs are very small and their small passages get blocked very easily. (Hello again, Benoit, my '93 B4 fuel injection project bike is still running great, pictured here out on the roads between Denver and Colorado Springs with my brother riding it during June of 2018. He's a bigger guy so he makes the B4 look like a really small bike)

Wondering if I'm reading/interpreting this statement correctly? I'm reading this as: The bike was running well, then had starter clutch problem which you fixed, and now it will not generate a spark. If I was troubleshooting that scenario I'd start looking right were the last bit of maintenance was done, especially since the crankshaft-speed pulse generator hardware is located right there on the starter clutch. Things like: are the two pulse generator sensors (variable reluctance sensors) that are located at the toothed-wheel portion of the VFR's starter clutch installed correctly? not damaged? are all the teeth (the little metal bumps that the pulse generator sensors are meant to read) on the perimeter of the starter clutch undamaged? is the "air-gap" distance between the sensors and the teeth set correctly? The bike's ignition control box won't command a spark if it doesn't receive a proper pattern of signals from the pulse generators. The bracket holding the pulse sensors didn't get bent, did it? Variable reluctance sensors are pretty sensitive to the "air-gap" distance between the sensor and the metal "teeth" spinning past on the perimeter of the starter clutch. Also, a damaged tooth on the starter clutch perimeter might not be "read" correctly by the sensors. And... you said that you replaced the starter clutch, right? Did you examine the replacement piece(s) to insure they were identical to the removed piece(s)? I don't know if there was ever a difference in the pulse sensor tooth pattern on the perimeter of the starter clutch, but if there are 2 (or more) versions it's conceivable that you were accidentally supplied with the wrong one.

My Iron Butt Rally hero: Kurt Worden riding a Kawasaki EX250 entered in the "Hopeless" class, finishing 21st overall in 2017. 9,690 miles in 11 days. (Photo from the finish line of the 2017 Iron Butt Rally)

Just trying to offer a solution that focuses on exactly the weak point in the VFR electrical system being discussed in this thread. When I offer a more comprehensive solution (one that goes above and beyond the exact scope of the issue being discussed) I usually get blow-back or dismissal, usually related to the price of what I'm recommending. So in this case I chose to recommend the cheapest, most tightly focused and expeditious solution.

Installing a VFRness will take the load off that part, and it'll help your Regulator/Rectifier and Stator last longer.

You should read through this thread here on the VFRdiscussion forums, it's recent and still active and I think it might have some information in it that could help with your problem. https://www.vfrdiscussion.com/index.php?/forums/topic/88125-5th-gen-bad-mileagerich-running-opinions-on-what-to-check/&tab=comments#comment-1088633

Makes you wonder how common this situation is. How many 5th Gens have a MAP sensor that isn't operating at 100%? And this would include any other VFR Gens that use the same model of MAP sensor. So maybe the 5th Gen VFR's MAP sensor slowly goes bad during an 18 to 20 year lifespan (which is where our 5th Gens are now). Based on your experience it appears the MAP can deteriorate and reach a point where it causes a noticeable fueling problem some time before the PGM-FI system senses it strongly enough to blink a code.

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Also, if I remember correctly the "glowing FI light" can be caused if somebody put LED bulbs in the instrument panel lighting, including the FI light position. You can put LEDs into every instrument panel position except for the FI light position. The FI light position has to remain old-school incandescent.

I think you might have a problem with your measurements (your multimeter testing results). If I remember correctly you're supposed to disconnect the stator from the motorcycle's electrical system for testing. If you test with the stator still connected to the R/R (and as a result, connected to the entire bike's electrical system) you'll get strange/unreliable results. I remember reading explicit directions in one of my motorcycle service manuals to insure the stator is disconnected from the system for testing. That's what Urbanengineer is referring to: However, the picture in your last post makes it look like somebody "hard-wired" the stator into the bike's electrical system, so you can't quickly disconnect the stator. Is that correct?

Beware, Regulator/Rectifiers are sneaky things. A failing R/R will sometimes give a good (enough) reading when the unit is cool, but after you've ridden for a bit and the R/R heats up its performance can change a lot (and usually for the worse).

Stop, Wait, Hold on for a moment... there might be a really easy, simple explanation for this situation. And it's an easy thing to check (just by looking at the front brake lever on the right handlebar) When people mess with the front brake lever on the VFR800 (like when they take it off to service/rebuild the front brake master cylinder) they sometimes put the plunger in backwards. I'm talking about the golden-colored piece of metal that transmits your hand-force between the "cup" on the inside of the front brake lever and the front brake master cylinder piston. When this piece is installed backwards it sets up a situation where the pressure from braking the bike cannot properly bleed off when you release the brake lever, so the pressure builds up (bit by bit) and locks the brake just as you described. I'm referring to part number 13 in this picture. If it's properly assembled it will look like this: You will be able to see the tapered portion of the part. If it is installed backwards you won't see any taper on the part.