Start button

[angus]

I suspect my start button may be dodgy have 3 wires coming from it 2 work the kill switch which I've checked and fun e which wires should I test for continuity for the start button or do I need to do it internally.It's my 80 550L.

[Steve]

There is likely a 3-pin connector where those wires connect to the main harness. Two of the wires should be orange/white. One of them will have a red sleeve over it. The wire with the red sleeve is the feed that comes from the fusebox, it should be live when the key is ON. On the switch side of the connector, that red-sleeved wire will feed the kill switch. The switched side of the kill switch has the other orange/white wire, it goes back to the connector to feed the coils and the ignitor. Also on the switched side of the kill switch is a short wire that goes to the starter button. I don't remember if it's actually a wire or just a trace on a ciruit board, but it does not matter. The switched side of the starter button will feed the third wire in that connector, it should be yellow/green.

With the ignition key ON and the kill switch in the RUN position, you should have power on both orange/white wires. Use your test light (or a meter), touch the yellow/green wire, then press the START button to see if you have power there. If you do, your start button is not at fault.

If you do see power on the yellow/green wire, put your test light probe on the solder pad on the starter solenoid that has a yellow/green wire. Press the START button, see if you have power. If not, check to see if your clutch "safety" switch needs to be pulled, as well. If you do have power at the solenoid, but the solenoid does not 'click', move your test light probe to the outer case of the solenoid and press the START button again. If you see power there, you need to fix a ground (earth) wire.

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[Redman]

I suspect my start button may be dodgy...................

Yes, would be good to check with a meter.

Would be good to describe why you suspect the start button. THe reason I ask is because I would more suspect the clutch interlock switch (if you have it still in the circuit) more than I would that start button for most symptoms.
If you puch the start button and nothing happens, keep same pressurfe on it and then release and pull back the clutch lever and wiggle it around some, if it does crank then you can suspect the clutch interlock switch. It is adjustable.


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[angus]

Redman the switch is disconnected what colour are the wires do you know and I'll connect them together to bypass it

[Steve]

The yellow/green wire that leaves the starter button goes through that 3-pin connector, then over to the clutch switch. It remains yellow/green until it gets to the solenoid.

The connectors that you will need to find to bypass the clutch switch will probably be found in the headlight bucket. Yep, yellow/green wires, with bullet connectors. Simply disconnect both pairs of connectors, then re-connect the two on the main harness. They are opposite gender, so it is easily done.

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[Redman]

Yep, What Steve said.

[angus]

Cheers I'll have a look later bike is basically a dismantled one no lights indicators or tank on it I'll post a pic later

[angus]

Replaced the green 3 pin connectors as they we're knackered,solonid ok when I connect the clutch lever wires(y/g) together bike wants to start without pushing button (like button is stuck on).If the new connectors were wired wrong the wrong way o & o/w wires were the wrong way around would this cause what's happening

[Steve]

Verify connections by referring to what I listed in post #2.

To verify whether your starter button is stuck, separate the (green?) 3-pin connector. Use your meter on the switch side to see if you have continuity between the yellow/green wire and either of the two orange/white wires (assuming the 'kill' switch is ON).

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[angus]

Steve cheers did your test and only continuity between the orange wires nothing when I touch meter of y/g and either of the orange wires

[Steve]

Showing continuity between the two orange wires shows your 'kill' switch is in the RUN position. You can verify that by checking continuity between the two orange wires again, but turn the switch to OFF.

With no continuity between either orange wire and the y/g wire, check again, but also press the start button. You should then see continuity.

If you see all of that happening, all the switches in the right-side switch box are working well.

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[angus]

Tested old switch worked fine (continiuty test),connected it to loom nothing. Found a fault no power coming to the g/y wire in the loom side of the switch connector I used the clutch switch g/y wire and starts when I press the button where does the g/y wire from the connector block in the loom side go to.Looking at my diagram it shows from start button to starter disconnect switch (is that the clutch switch??) and from there to solonid.

[Steve]

The "starter disconnect switch" is, indeed, the clutch switch. Did you find the connectors in the headlight bucket? I could not tell where you found the fault. One of those y/g wires comes from the starter switch, goes through a bullet connector to the clutch switch. On the other side of the clutch switch, it comes back through another bullet connector and goes to the solenoid. If you separate the bullet connectors, you can bypass the clutch switch and send the starter button wire directly to the solenoid.

If you don't have continuity from the start button to the bullet connector, it will be easy enough to find where the break is and replace that section of wire to restore proper operation.

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