[ckenwright]

Suspend the rear wheel, start the bike and see how much the rear turns or if it continues to die. If it dies you have an electrical issue. If not and the wheel spins you have a clutch issue.

Suspend it with a center/ rear stand or hang it from something.

[waffenampt]

popstart

Push the bike down a hill then pop start it in second gear. It should turn the motor over even if the clutch is stuck together. If the motor turns over u know its not the tranny.

[smartone1971]

Push the bike down a hill then pop start it in second gear. It should turn the motor over even if the clutch is stuck together. If the motor turns over u know its not the tranny.

thats a good one, one last thing on electrical( relay ) than it mechanical.

[paul.miner]

I made this wiring diagram to help diagnose the problem:



For the ignition to work, the fuses must be good, the diodes should be good (more on this later), either the sidestand switch or the neutral switch must be closed (sidestand up, or gearbox in neutral), the sidestand relay must work, and the run switch must be closed (engine stop switch in the run position).

For the starter motor to engage, everything listed prior must work, plus: the clutch switch must be closed (clutch pulled in), the starter switch must be closed (pressing the starter button), and the starter relay must work. I noticed my bike doesn't even have a clutch switch, so that part of the circuit is always shorted for me.

Regarding diodes: The diode on the right isn't particularly important to the function of the bike. If it's shorted, it shouldn't change the behavior. If it's open, the neutral light won't come on.

The diode on the left is more important. If it's shorted, then the sidestand switch can also activate the neutral light (sidestand up would make the neutral light come on). If it's open, then the ignition won't work unless the sidestand is up, regardless of whether the bike is in neutral.

If the starter motor turns when in neutral, but not when in gear, then it looks like the only possible electrical problem is the sidestand switch. One side of the switch should read battery voltage, the other side should read ground (not just open, but ground!)

Otherwise, I think you're looking at a mechanical problem. If the battery voltage drops considerably when you try to start it in gear, that indicates the starter motor is being engaged but can not spin at all. If the battery voltage rises a bit, that suggests the starter motor is not being engaged, and all you're seeing is a slight rise in voltage from the headlight going out.

[downsey]

well i ran out of gas yerterday and it started raining . so i will resuse the reserection today . going to suspend the rear wheel , jump the relay , and maybe rewire how the side stand switch is according to the schematic . thank you all who have gave advice will report my results back today .

[GytRDunKat]

Sheesh Paul, nice post!

[paul.miner]

I helped a guy diagnose why his GS500 wouldn't start (turned out the clutch switch was not being engaged by the clutch lever), and it got me thinking that diagnosing the problem would've gone a lot faster had I redrawn the wiring diagram to include just the relevant parts, and arranged it so the dependencies were clearer.

I didn't fully understand the dependencies until I sketched it out on paper. The relays are triggered in different ways as well: the sidestand relay's coil has power on one terminal, and needs the other terminal grounded to trigger it. The starter relay's coil is grounded on one terminal, and needs power on the other terminal to trigger it.

[smartone1971]

paul great post, that will help him alot to understand.

[downsey]

well **** put gas in it . and battery was drained over night , i usually bring it in but left it in the bike over night . any way by the time i charged it up starting raining again ! will try again tomorrrow and post results ....

[ICEG]

try moving the bike back and forward and change through the gears

[downsey]

damn it bike wont start now .turns over but dustent fire up . at my whits end

[waffenampt]

take some plug caps off and check 4 spark, u using the choke ?

[arsenic]

ok, I'm gonna be captain obvious and repeat what everyone else said already. the reason it won't start - BATTERY. The reason it dies when you put it in gear - SIDE STAND SWITCH. How many people have to tell you that?

[smartone1971]

ok, is it getting spark?
do you have a tester? volt meter. check the connector that gos to the side stand switch (with it up) or the swith pushed in. is there continuity there? if so the switch is good. check the relay next put voltage across term 1 and 2 (thats + to 1 and - to 2) there should be continuity between term 3 and 4. with the relay unpluged if there is than it is good. i will put a wiring diagram in my garage pix if you need it. lets see whats up with those three things and go from there.

[downsey]

gets spark pulled all of them out . and yes captain obvious side stand is bypassed, battery is new