Weird Electrical Gremlin

[merlins_hat]

I'm having a very strange issue with my 1999 SV650 and have been battling it for weeks.

Video found HERE that shows the problem.

Essentially the tachometer has a mind of it's own, the indicators are both constantly on, as is the headlight, and the dash lights blink on and off.
Bike is also difficult to start without a booster attached; the starter kicks back.

Problems started when the battery slipped in it's cradle and the positive terminal shorted to the chassis.

Have replaced:

Reg/Rec
Battery
Stator
Instrument cluster

Problem remains the same.

Prior to this (and likely reason the battery moved) I was chasing charging issues on the bike. The battery moved whilst riding, tachometer went all the way around to redline but the engine died. All above parts have been changed SINCE this latest issue (i.e. I'm not on my THIRD battery and reg/rec).

When it does run (As per video), I get 18v across the battery! This has been happening since before the incident.

I'm completely out of ideas as to what is going on. To the point that I want to throw the bike away before it costs me any more in parts!
Any help and advise gratefully received!

[garynortheast]

I think I'd be looking at the loom for something burned and shorting out somewhere. A multimeter and time spent checking may get to the cause.

[R1ffR4ff]

As Gary says look to the Loom and ALL block connectors.Also if possible if you have a Garage or a quiet-darkened place see if you can see or hear some electrical tracking/crackling/shorting.

See if anything happens different when you move the bars.Also take out and check all fuses for corrosion.You can buy a big box of the fuses used on these Bikes from Halfords at a decent price.Just take one with you as IIRC they are the mini size.I keep spares under my rear seat.

[Seeker]

What happens if you disconnect the R/R from the battery and start the bike? Obviously the battery voltage will now be 12.something and decaying but does the tach work normally?

The a/c output from the alternator is governed by the magnetic field strength of the rotor, the number of wires in the stator coils, the gap between the rotor and stator and the speed of rotation - none of which change except engine speed so if you're getting 18V DC across the battery it implies that either you have a wonky meter or a bad r/r. Some digital meters don't like being near an ignition source and can yield faulty readings. Does your meter read 12.X with the r/r disconnected and the engine running - that will tell you if the 18V DC reading is genuine with the r/r connected.

Definitely a weird problem. If your r/r is putting out 18V, I'm surprised your bulbs haven't blown (along with everything else).