[dickim]

Maybe pull that clutch lever plug and maybe (via a small blade fuse ) create bridges between the 3 wires, if it works Pblm identified.  I know on one thread someone replaced switch and all good for a WHILE!!!! Am convinced my issues which appears same are in that switch.

[AzCal Retred]

All that barrister driven frippery doesn't pertain to moving the machine forward, it's just a PIA/profit centre for others as it ages, corrodes, or otherwise degrades. People rode for many years without any majikal interlocks at all, just pay attention when starting. I knew guys that rode the last 50 yards home on their old out of gas Hondas using the starter PB because they were too lazy to get off & push. It's your machine, if a feature isn't adding value, change it. The only thing keeping you "safe" is YOU operating your machine mindfully, not rotting-in-place interlocks.

[dickim]

Agreed- Personally never start anything without using the clutch -  safety feature built in brain memory!

[Willie]

Fuzzy Electrical diagram here:
https://accessories.hitchcocksmotorcycles.com/Workshop-Manuals-To-Download

The starter is shown. The starter relay grounds thru the clutch lever switch, so it looks like anytime the clutch lever is pulled the starter should operate, after the ?kill switch? is on and the Start PB in the right side handlebar switch is pushed. As the relay grounds thru the ECU if the clutch switch isn't engaged, the ECU is deciding for you if the clutch lever isn't engaged, likely also looking for the neutral switch and that the motor isn't already running. But seeing as how the neutral switch tends to get too grungy to work, maybe that's kind of a a "non-starter"....

The Pre-Unit ES's have a relay that blocks the starter PB by sniffing the rotor AC, maybe that could be bootlegged in there to avoid accidentally operating the Start PB whilst the engine is running. Personally I'd likely just add the "Catastrophic-failure-blocking, no-start-when-already-running" relay & just de-fang the Clutch & ECU portion. I don't think it's too hard to verify you're in neutral or the clutch is pulled in before starting. Or just toss all of it and keep your darn thumb off of the "Start" PB when you don't need it, maximum simplicity yielding max probability that it'll function when you ask. Just put it all back before selling on, eh?

I think that I get what you are saying, but just to clarify - the NO START also occurs even if I keep the clutch pulled-in.  What does this tell you?  I am not really sure what the heck it tells me.  As the old canard goes about a Thermos that can keep things hot or cold - "How does it know?"

[dickim]

Tells me that the clutch lever switch is not getting the grounding through light or over ride cables of pulling lever, could be the other  end of the cable.......
I understand (but am often wrong) that feed or grounding comes from one of the 2 cables to the 3rd, hence joining them disables the need for neutral or clutch pulled in to allow S.Motor to crank....

[Haggis]

Clutch swith provides a direct earth when pulled.
Or a connection to the neutral switch when out, which provides an earth if its in neutral.
No neutral no earth.

[axman88]

Thanks Haggis,
That's a much better schematic than comes in the owner's documentation, which doesn't even clearly show the interconnection dot at the brown wire junction where the clutch switch connects to the neutral sensor.

The first suspect I'd have would be that connector marked AA at the starter relay.  I'd start there by disconnecting that connector and verifying that there is 12V on the (purple?  gray?) wire with the starter button pushed, and no ground on the black wire with the bike in gear.  Then I'd tie the clutch switch into the pulled position and see what needs to be wiggled to get ground to show up on the black wire.

It's not impossible that multiple intermittent points exist, or that the issue is on the B+ side.  The B+ ( battery positive, aka 12V) side of the circuit goes upstream to the battery via the kill switch, ignition switch and 20A fuse.

[AzCal Retred]

Like Axman88 says, there are likely multiple failure points here. Few situations are "clean".
1) Check & clean your ground points, verify LOW resistance between motor housing and battery (-).
2) make CERTAIN the starter solenoid picks up every time +12V gets across its leads. Measure batt (+) voltage drop across solenoid when picked up. Measure actual ground resistance between start solenoid output side and ground when the clutch handle is pulled in.
3) make CERTAIN that the starter solenoid high current contacts can actually, repeatable carry the 30A-50A of the starter motor. Their internal resistance has to be < maybe 0.1 Ohm or else current heating can eat them up (IxIxR=Thermal Watts). Measure when picked up with a good meter
At this point, the "big picture" stuff is proven to work, the rest is control circuit logic. In Neutral, Key ON the starter should work, so measure the ground path between the start solenoid output side and ground. Just pick it apart, bit by bit. It's DC, your meter will read it.

The part that bothers me about the Haggis WD is that I'm not seeing any blocking of the start relay after it's running. If the proffered diagram is correct, 12V applied to the Start solenoid in Neutral at 4000 RPM would politely engage the starter. The Pre-Units had a special relay, but the EFI Module could easily accomplish that function. Can the start mechanism on the UCM withstand being operated when the engines is already running? If not, maybe there is more going on electrically than the WD is showing, or RE left in a source for billable repair shop hours.

Anyway, if operating the starter with the already engine running isn't blocked, worrying about gearbox neutral or the clutch isn't buying you too much. More better it works every time you ask it to, you don't need to fight the equipment. Simplify it and go riding. Keep your thumb off the start PB unless you are serious.

[Haggis]

Yes, I can spin up the starter motor when the engine is running.
Causes no problems as the crank is spinning faster than the starter motor can ever go so the sprag clutch is just free wheeling it's way round.

[AzCal Retred]

Haggis - do you know if this is essentially the same scheme as the Pre-Unit sprag starter clutch set up? I've never seen the inside of either. If so, then there's not much need for a blocking relay in those also. That would make my life simpler as well.

[Haggis]

The sprag clutch only works in one direction. It can only drive the crank when it is turning faster than the crank. Once the engine starts the sprag has nothing to grip on. You can press the start button and hear the starter whizz round but it's not driving anything. It's not like a pre engaging bendix starter, ie bmw, where it would cause damage trying to mesh with a spinning flywheel.

[dickim]

Thx  Haggis for a succinct explanation of what I was trying to say re clutch lever switch 👍

[Willie]

OK!  I promised a resolution summary, and here it is:
First, let me share the convenient, face-saving "Repair Resolution & Credit Therefore Rule".  I established this Rule early in our (so far!) 48 year marriage.  The Rule goes something like this:  If something is broken and you fix it, you are not required to reveal exactly what the problem was and what ingenious steps you took to fix it.  This rule is especially helpful when you fix something, but have no idea exactly what was wrong with it, and/or how in the world you managed to fix it.  The bottom line is that you still get credit for fixing it, even if all it took was a swift kick to the item, followed by a few uncivil exclamations.  You fixed it!  You get full credit for the repair.  You are not required to provide an accurate, detailed and true explanation of how you did it.  Gratitude from the less skilled and uninformed family, friends, co-workers (this rule applies especially well to copy machines!) is still required, even if you keep the fix a mystery.  This handy rule has saved me a lot of time over the years, and preserved my perch as the Premier Repairman of the family   I hereby invoke the "Repair Resolution & Credit Therefore Rule" regarding this post and problem.
I FIXED IT!  I ran a number of tests with a multimeter on each associated circuit and part, and all results were within normal ranges - no voltage drops, resistance, or continuity problems.  I tried disconnecting the sidestand switch, but this had no effect.  I inspected the condition, cleanliness, and tightness of all the connections involved; all of which were in good order. I tested the battery voltage under load.  None of these interventions proved effective.  No clicks, no buzzes, no sparks or smoke, no start. 
Beginning with the starter motor, and working back through the entire system, I disconnected, inspected, cleaned, and re-connected every circuit, switch, relay, and fuse on both positive and negative sides.  When I was done, I went back through and re-inspected every connection.  Then, I walked to my other bikes, and loudly praised them for their easy starting and high reliability.  I then buffed them gently with a soft microfiber, and loudly admired their ruggedly handsome good looks, and awesome speed and handling.  Meanwhile, the errant Bullet took all this in quietly and stood off by himself, smudged from the recent repair efforts and cold as a glacier from not starting and running.
There's a lot of other highly technical stuff I did (sticking out tongue in proper position, singing along with Lynard Skynard, and a bunch more!) but under the "Rule" I am not bound to reveal all my secrets to you.
Finally, I spit over my left shoulder first, then my right shoulder, verified that the sidestand was up and the kill switch was off, and the bike was in neutral.  Then I turned the key to start, muttered a few inspirational and encouraging words to the Bullet, lightly pressed the start button, and......VAROOM!  Immediate, flawless, and admittedly quite exciting start!  I shut the bike off, waited a couple of minutes, and ROAR!  He started smoothly and instantly.  Over the next few hours I returned at different intervals and was rewarded by immediate and strong starts each time.  I FIXED IT!
I have told you all you need to know about my success.  If you have any questions, don't bother, as I have invoked the "Rule" and I have no intention of revoking it.  I hope that forum members will find this post especially helpful.  Stay tuned for my next highly informative "I FIXED IT!" tutorial, and thank you for your suggestions and interest.

[dickim]

Congratulations and I'm adopting your rule 

[AzCal Retred]

Geezer @ #27:  Welcome to the world of Bullet Tsukumogami. They like to test you, and regular ritual sacrifices of parts, top-tier lubricants, an occasional bit of skin & blood, and copious attention seem to keep them content. Well Done! 

https://en.wikipedia.org/wiki/Tsukumogami