Folks,
I’m seeking help to diagnose a non-starting Tenere. Please forgive the following long pre-amble. I’m restoring a “paddock find” 1986 1VL Tenere (Australian equivalent to a Euro 1VJ, I believe). The previous owner said the bike was running prior to being parked up outside under cover some years ago (~10 ?). The mileage is unknown and the bike is in a poor cosmetic condition. The lights, instruments, switches and battery had all been stripped from the bike which was operating on CDI ignition only. The wiring loom had been hacked accordingly with the addition only of an after-market kill switch.
After doing some basic initial maintenance (e.g. free-up throttle and choke cables, new oil, fresh fuel), I got the engine started relatively easily with the kick starter, albeit it ran very roughly (not surprising given how long it had not been run). I ran the engine in short bursts (few minutes) two or three times before it refused to start anymore. My plan then was to restore the instrument, lighting and starting circuits so I could confirm the electrics and e-start work before trying to re-start the engine and (hopefully) confirm it has no major faults. A full bike strip down and rebuild would then follow.
I’ve successfully restored the electrics using a complete (used) loom and have the lighting, indicators, instrument lamps and starter motor all working. I’ve stripped and cleaned the carby and replaced the intake boots with a couple of good spares. I have a continuous spark when holding the plug against the engine fins and turning over the starter motor but the spark looks weak and makes no audible noise. Through basic troubleshooting and swapping components with a fully working 3AJ I also possess, I believe I’ve eliminated the following possible causes of the non-starting engine:
Fuse
Spark plug (new one fitted, gap correct)
Battery (new one fitted, voltage ~12.3. Possibly a little drained from all the unsuccessful e-start attempts)
Switches – Ignition (after market, continuity tested ok), clutch (bridged out), neutral (continuity tested ok). The 1VL did not come with a side stand switch.
Coil/plug lead/plug cap – 1VL unit swapped onto 3AJ which then started and ran ok.
CDI – Tried 3AJ unit on 1VL, weak spark but no start.
Bad grounding: I’ve run an extra grounding lead from the coil -ve terminal to battery -ve terminal and from engine fins to battery -ve terminal. Still no start.
Stator Pick-up (excitation) coil resistance: Target 90-130 Ohms, actual 113 Ohms (G-W/R, G-W/G)
Stator Source coil resistance: Target 110-170 Ohms, actual 137 Ohms (R-Br)
Engine compression: 140 PSI
I was expecting a strong blue spark with an audible noise but this is definitely not what I’m getting. I’m running out of ideas, thinking it could be the source coil on the stator but the resistance readings check out ??
Welcome any advice/suggestions.
Thanks
PS: Can anyone confirm that the aftermarket Electrex brand G45 stator definitely fits a 1VJ engine? https://www.electrexworld.co.uk/acatalo ... XT600.html

Bang on with electrex G45. I have one fitted.
Also their original looking coils and regulators.
My 15 amp fuse used to blow when I had a cable damage short (intermittently when turning the bars), but she’d continue to run poorly without it.
The wiring diagram is on here somewhere, and at least still on the net, so when the ignition is on, check you have voltage to and from the switch on the bars, and up to the coil.
Sorry if I’ve missed any details on the post, but if you haven’t yet, do the usual hard start fluid into the carb and see if she wants to go. If she does, bad settings or shite been sucked into carb. If she doesn’t, keep looking for the ignition fault.

If there’s no supply to the switch, I’d Look for a missing sidestand switch. I know the standard didn’t come with one, but my one came from an ‘87 bike which did, maybe the previous owner had changed it?
Is there a supply to the clutch switch too?

Oh and after pissing around with the carb for years, (poor running not failure to start) when I put the G45 in she improved instantly.

The gearbox neutral wire gets damaged running through the side casing, and so can other stator wires. Can’t upload photos but just found my 2022 pics of stator comparison. My old one looked terrible. Can’t get (as far as I know) a replacement pick up though, so test that.
But the electrex stator swap is one of the best choices I made.

I'll order a new stator. Even if it's not the root cause of the current non-starting issue, I figure it's prudent to replace it given the engine is 40 yo.

Some aftermarket stators do not have the correct direction for the ignition winding. If the spark is weak, and you experience some kickbacks, swap the connection of red and brown wire around, as the CDI is very specific to this.

Andy