76 R90/6, no action when I hit starter button

[Djohnson1967]

purchased at estate sale, been "piddling" with it for 6 months, finally got it on the road ! 12 miles day 1, 25 miles day 2, 50 miles day 3
today, it died when I had to make a hard stop and then nothing when I hit starter button:
I have lights etc so power is there. Battery reads 12.6 V. When I hit the starter button, I hear slight "click" from the relay. IF I turn the kill switch off, no click, so I think that says my problem is not the kill switch.
Its in nuetral (lights on etc)tried clutch in, clutch out. I cleaned all terminals on the relay.
removed starter cover to expose it. I have 12+volts to the main terminal on the starter. No voltage at the small "spade" connection when I hit the starter button. This is the wire from relay to starter.
If I jump 12 V to this small spade terminal, starter works. Tested continuity in the wire from relay to terminal, it is all good.
Wiring diagram shows blue yellow wire from starter switch to relay, I get no voltage there when I hit starter button, but
Remember, i am getting a "click" from the relay when I hit the starter button,

Any thoughts out there??

Don j
08 RT,03 GS650,76 /6, and too many jap bikes to list

 

[DonTom]

Tested continuity in the wire from relay to terminal, it is all good.

Check with a voltmeter, not an ohmmeter. IOW, when you hit the starter, make sure the voltage does not drop on the wire itself.

If the wire is old, or a bad connection, the ohmmeter could show a normal low resistance reading but the voltage could drop under it's normal load from the current heating up the wire. In some cases, just a little current is all it takes for the voltage to drop. The ohmmeter requires still much less for a normal reading.

-Don- Reno, NV

 

[69zeff65]

Check your ground too.

That ground strap is bolted to one of the worst (wurst) places it can be, I would check and make sure the main battery ground is good and then take a close look at the starter relay connections. If you get a click from the relay chances are everything before it (push button, kill switch, clutch switch, neutral switch) are good and doing the job. Check your grounds and battery cables and go from there.

 

[typ181r90]

Still may be the relay, a clicking relay doesn't necessarily mean a functioning relay. I just fixed a client's Ducati that wouldn't start, had me scratching my head because I went through the whole bike and the main relay would click and the lights would flash momentarily. After opening it up the contact was all pitted and had to be replaced, it would click when it got power, but just kinda crapped out after that. There's some pics of the relay internals here

 

[Djohnson1967]

relay or not?

i'M LEANING TOWARDS RELAY TOO. remember, I can get the starter to work when I disconnect the wire from the relay and feed 12v direct to it, so I think that rules out the ground possibility
Does anyone know what voltage I should expect coming from the starter button to the relay?
I think my next step is to open up the relay and see what it looks like. i know thats not "normal", but then neither am I.
Don j

 

[DonTom]

i'M LEANING TOWARDS RELAY TOO. remember, I can get the starter to work when I disconnect the wire from the relay and feed 12v direct to it, so I think that rules out the ground possibility
Does anyone know what voltage I should expect coming from the starter button to the relay?
I think my next step is to open up the relay and see what it looks like. i know thats not "normal", but then neither am I.
Don j

Try shorting out the relay contacts (not the relay coil!) with a clip lead.

-Don-

 

[DonTom]

Does anyone know what voltage I should expect coming from the starter button to the relay?

When the relay is energized by the relay coil, both relay contacts should have the same voltage. There should be no noticeable voltage drop across the relay contacts when it is energized by the relay coil. A relay is just a switch that is activated by the coil.

While I would assume that voltage is close to the battery voltage, I cannot say for sure because I am not sure about how the R90/6 is wired up.

-Don- Reno, NV

 

[Djohnson1967]

voltage , wire from button to relay

switch on, wire had 12V+ to it(connected to the relay
Starter button pushed, drops to 5.6 V
Tells me it is a "always on" relay, and the button push causes drop on voltage, causes it to "trip open", and cause the circuit to flow 12V+ to the starter solenoid. 'cept ain't happening!
Tomorrow, I am removing the relay, opening to check it out.
Stand by for breaking news update

PS, opened up the headlite, stared into the deep dark mess of wires, pulled the clutch safety switch wire, grounded it, no help! grabbing at sraws

 

[DonTom]

switch on, wire had 12V+ to it(connected to the relay Starter button pushed, drops to 5.6 V Tells me it is a "always on" relay, and the button push causes drop on voltage, causes it to "trip open", and cause the circuit to flow 12V+ to the starter solenoid. 'cept ain't happening!
Tomorrow, I am removing the relay, opening to check it out.
Stand by for breaking news update

I seriously doubt that a starter relay will be of the "normally closed" type. It sounds to me more like the load is dropping the voltage to the starter.

Did you check BOTH contacts of the relay? The input as well as the output? Or simply short them both and see if the starter runs? If you have the full 12 volts going into the relay and only 5.5 volts out, that will be a bad relay contact, when relay coil is energized (I am assuming it's a normally open relay, as I can see no reason for a normally closed relay in a starter circuit) . If the voltage also drops at the 12 volt input to the relay, either there is high resistance dropping the current before that point or something after that point is drawing too much current.

-Don- Reno, NV

 

[Rod Sheridan]

switch on, wire had 12V+ to it(connected to the relay
Starter button pushed, drops to 5.6 V
Tells me it is a "always on" relay, and the button push causes drop on voltage, causes it to "trip open", and cause the circuit to flow 12V+ to the starter solenoid. 'cept ain't happening!
Tomorrow, I am removing the relay, opening to check it out.
Stand by for breaking news update

PS, opened up the headlite, stared into the deep dark mess of wires, pulled the clutch safety switch wire, grounded it, no help! grabbing at sraws

Make sure the alternator rotor connection isn't open.
(Alternator field)

That will prevent your starter from engaging...........Rod.

 

[pglaves]

Make sure the alternator rotor connection isn't open.
(Alternator field)

That will prevent your starter from engaging...........Rod.

Huh???

 

[James.A]

Huh???

It will, for sure, drop the starter on a /5.

 

[Djohnson1967]

alternator rotor, open?

I'm with Paul: huh? so how do I test that?
I pulled the relay apart. contact points look great. I can make the points open/close on the bench. don't know how to test it any further than that.

been a busy day, will reassemble it, reinstall it and see whats my next step.
PS to Paul G. glad to see you chime in, was hoping you one have a revelation for me.

Don j

 

[James.A]

I'm with Paul: huh? so how do I test that?
I pulled the relay apart. contact points look great. I can make the points open/close on the bench. don't know how to test it any further than that.

been a busy day, will reassemble it, reinstall it and see whats my next step.
PS to Paul G. glad to see you chime in, was hoping you one have a revelation for me.

Don j

I wouldn't bother unless you are at wits end and want to know for sure on that.

The /5 starter relay, as originally configured, has an analog logic circuit in the design to prevent engaging the starter while the motor is running. It is called the anti-restart circuit. If the motor is running and idling fast enough to dim out the charge light, the starter will not engage. One side effect of this feature is that there needs to be continuity thru the alternator rotor for the relay to engage the starter. I believe this function is unique to the /5 electrical system.

To test the rotor, you must remove the front cover and slip a business card between the brushes and the slip rings of the rotor and then set you meter to ohms to check for continuity of the winding.

 

[fuhgawee]

+1 on starter relay.

I had random starter issues, replaced relay. No problems since.

There I jinxed myself

 

[Djohnson1967]

relay to replace or not;

I 'm at the point where I am ready to throw money at it, so will be looking for a relay.
thoughts other than dealer NOS?

 

[20774]

Personally, I like OEM stuff, but Motorrad Elektrik and EuroMotoElectrics offer relays as well. You want part number 61 31 1 357 104. Motorrad Elektrik shows one for $10...that almost seems way too low, but who knows?

 

[Djohnson1967]

ordering a new one

gonna just buy new one from Ricks Motorrad Elektrik on Monday... will post results

 

[DonTom]

gonna just buy new one from Ricks Motorrad Elektrik on Monday... will post results

Don't expect it to work if you tried to short out the contacts with a clip lead and that didn't work.

But good luck anyway.

-Don- Reno, NV

 

[Djohnson1967]

problem solved! It was the relay

Anyone else have that issue, dont mess around, contact Rick at Motorrad Electrik
$12. + shipping and you are back on the road!
Thanks Rick!