Help - GPZ500 wont start

Anyone any idea why my bike started ok yesterday morning but failed to
start that afternoon, flattening the battery. I charged it up and today
- still no joy. Smells like plenty of fuel but not a peep of a spark?
1991 model.

Ta

 

What do you mean, "not a peep of a spark?" ? Did you actually pull the
spark plugs out and ground them and crank the engine over to see with
your own baby blues that there was no spark?

There's NO standardized wiring layout for sidestand switch, neutral
switch, kill switch, and clutch interlock switches. You can crank the
starter forever on some manufacturer's machines even with the kill
switch off stopping the ignition from firing while the starter grinds
away...

Others won't let the starter solenoid work with the kill switch in the
OFF position.

Check the side stand switch to see if it's not making good contact.
Work the sidestand up and down and work the switch button to see what
happens when you try to start the engine.

I was trying to start my KLR-600 dualsport and the battery was getting
weak so I tried to kick start it and my knee hit the red knob on the
kill switch. Broke the damned knob off the $55 USD switch. Then the
engine would start off the kicker, but electric starter wouldn't work.

I discovered that the signal generator pickup coil was grounded or
ungrounded by the kill switch with one set of contacts, while the
starter button was energized by the other set...

You could have a problem where you have power to the ignitor box, but
the signal generator doesn't manage to get its pulses to the ignitor
box and the engine would never get a spark. Or, you could have a
problem getting power to the ignitor box or to the ignition coils.

If you really truly haven't got "a peep of a spark" it's time to study
the wiring diagram in the owner's manual.

 

Just to clarify what Krusty said regarding interlocks. On my 305 the
starter will only turn if the interlocks are OK, ie: kill switch, side
stand switch, and gearbox/clutch switch. So if the starter turns, you
have an ignition circuit.

Looks like your problem is either the CDI, rectifier, magneto or
associated wiring.

Check for corrosion in the connectors, otherwise its a process of
elimination.

If you don't have a wiring diagram, check out the English version of
Lothar Conrads web site for the GPZ-305 www.gpz-305.de, I believe the
wiring should be the same.

Good luck

 

Thanks for the advice guys, I'm coming to the conclusion it's something
blown on the ignition side but am now going outside to check the
sidestand switch.