I would make a list of possible components and components you have checked. If everything was fine, you would get a spark, so something must have been missed. Its almost certainly a single item common to both cylinders or you would get one spark. Perhaps start at the ignition switch and trace the current from there, to see how far it gets. Does it get as far as the fusebox and if so, does it get to the next component? I seem to remember replacing a relay underneath the tank, on the right-hand side and as I've said, I had enormous trouble with the uppermost 30 amp fuse connecting to the fuse-holder properly - have you checked that out? What I don't remember is whether that fuse prevents the starter from spinning but that's easily determined by taking the fuse out and seeing if the motor still cranks. If it doesn't, then that fuse is probably not the problem but if the motor does still crank, it could be.
Looking at this, the current going through the relay and fusebox all goes to the starter motor. All current for the ignition system appears to come from the kill switch via a brown wire. Do you have current to and from the kill switch? @Derek is really hot on electrickery and used to have an SS himself - any ideas Derek??
Thanks for the diagram, at work at the moment without the manual so that's a big help. Looking at that I'd say if the fuse was an issue the bike wouldn't crank. I'm thinking it could lead me back to the battery. Voltages look OK but I don't know how badly a slightly lower battery voltage would affect the ignition. Will have a look again tonight.
It's good to see everyone trying to help, this is not a 'we are stumped' problem but an 'any help is only of the remote kind' problem.
Yes, I must say this is all greatly appreciated. I promise the assistance will be returned once I've learned enough myself!
I had no cable kit on my SS and it was always a reluctant starter. It was almost certainly bad practice but I used to leave the battery charger connected if it was particularly reluctant. You could possibly try that or even use jump leads. That would certainly prove if it was the battery or not. Make sure you connect up to the right terminals though - someone on here didn't and fried their electrics...
thinking about it I recently had a similar problem with electrics found it was a fault within the ignition switch itself but not sure if your wiring is standard and not butchered that it would allow it to turn over and no ignition
Hmmmm...it's back to wiring and component checks for me I think! Hooked the bike up with jump leads and there's still no spark so can rule out weak battery as the primary issue. In other news rode a 748 today, loved it, good price too. This bike could be on borrowed time.
An update! First off no 748 for me, just had a big tax bill confirmed so it looks like I'm stuck with this pain in the arse for the foreseeable. Don't get me wrong it's a lovely bike to ride, it's just I'm kind of fed up with the problems. Been out and spent a few hours on the bike again today and I can confirm that I have 12V all the way to the coils and ignition control units, still no spark. I'm thinking it has to be the control units as the coil resistances check out OK and so do the HT leads and caps. Seems odd for them both to go but stranger things have happened I guess. As I have said before I've also ruled out poor battery condition and the pick-up air gaps and resistances are spot on. Any other ideas before I start replacing components? Anyone got any spares that they could lend? Thanks in advance :smile:
Is the earth good to the ignition circuit? There's a single 2 pole connector on the rhs of the airbox that feeds the ignition coils, ignition boxes. This feeds 12V, which you've checked, but also the only earth. Pull the connector and check for 12v across the connector.
It would seem odd for both to have gone, unless you killed then somehow. Are your sure you're testing properly for a spark? Presumably you're earthing the spark plug body properly?
I think so, plug in the cap, body placed on the cooling fins on the cylinder. How would I go about killing the control units? As unlikely as it is anything is possible with my luck at the moment.
The big 30 Amp fuse by the side of the battery only protects the OEM reg/rec...........if the reg/rec has been changed for an RR51 Electrex type, then the 30 Amp fuse and +ive is defunct and does SFA...........unless the RR51 has been fed from it.
Iirc, the earth is off a common in the loom. Before you go chasing wiring, just drop a meter across the connector (loom side) and see if you get 12v. You can see the connector in the wiring diagram. Marked A B just prior to the ignition components in the bottom left corner. Just one further 'tip'. The wiring diagrams in the Haynes are pretty good, certainly easier to follow than the early ducati manuals. However, wiring colours can be a bit hit and miss.
I've no idea where this figures in all of this but I know the bike is still on the original reg/rec. checked fuse and its ok, assume the associated wiring is also fine as the only electrical function the bike won't perform is a spark.
Thanks Nelly will check that in the morning, I've had that connector apart and never though to check across it. I've got the Haynes manual, it's been a boost so far.
That sounds pretty normal. I seem to remember there's something you're supposed to avoid doing - turning the engine over with plug caps disconnected, perhaps? @nelly is the expert though.
