Can anyone explain how the 1150 starter works

[roddy]

ok guys,
I have checked yet again and I am getting 12+v between the black wire and the chassis (wire disconnected from the starter motor) when the ignition is on.

This is correct the 12v is coming via the LRR coil but since you've disconnected the black wire the 12v can't return to earth so you'll show a voltage between the wire and chassis when disconnected.

reconnect the black wire and the ignition on, bike not started, check it again it should read 0v

If I pull the load relief relay out I don't get any voltage until I press the starter button when I get 12+v between the black wire and the chassis

thats sounds correct the 12v is now being supplied via the starter relay

I'd recheck your handlebar switch and strip the starter down to it's component bits, I'm unsure about starters fitted to 2002 models but the later ones can be stripped down to major parts quite easily I think there was a couple of rivets that needed drilling but these where not important.
if I remember correctly the contacts for the starter motor are at the end of the starter motor shaft, under the black cover.

the solenoid throws the starter shaft out into the ring gear at the other end of the starter shaft the contacts are made which powers the motor so spinning your engine to start, once you release the starter button the solenoid powers down springs push the starter shaft back to it's resting position and the starters contacts are dis-connected by the action,
if you contacts are worn/damaged thay maybe makeing contact hence the self starting or the throw of the starter motor isn't as good as it should be.

 

[TangibleSolid]

Thanks for all the replies guys, this kind of support is why I joined the forum in the first place.

To answer 'Greg', the bike is an '02 1150 GSA.

To answer 'Roddy', since the problem 'started ' I have had the starter motor unit out and cleaned and checked it as far as I could, although I didn't drill out the rivets to get the armature out. I did however remove the end cap and clean and check the main contacts, brushes etc.
I removed and cleaned the solonoid 'plunger', spring and lever
I confess that I was stumped by the solonoid unit itself, I could find no way to take this apart so I left it.
I put the whole thing back together and although it worked, I still have the intermitant starter engagement while running problem

based on the principal that I've eliminated everything else, I think I'm going to replace the complete starter unit unless someone can suggest something I havn't tryed/checked/tested

Thanks again

 

[roddy]

i'm at a wee bit of a loss on this one ?

the only other thing I can think of is there various diodes on the starter circuit clutch/sidestand (I think I don't have the manual with me) if one of them is failing ? sending 12v to the starter.

I'd be very surprised if it was the starter. could a local motor works not check the starter for you might save you a bit of grieve ?

 

[Greg Masters]

To answer 'Greg', the bike is an '02 1150 GSA.

My bike is a 2000 1150 and so is the wiring diagram I've been looking at. Unless they changed things around, you should NOT have any voltage on the black wire until you hit the start button.

I checked that on my bike and it concurs with my reading of the diagram.

If you think there should be voltage on that wire, how does the starter know when to run?

I don't think that your starter motor is at fault. You really need to understand where that voltage is coming from.

Greg

 

[TangibleSolid]

Just a bit more information...
I have just checked the black wire with it connected to the starter and the ignition on as 'Roddy' suggested above....
There is almost no voltage (0.02v)

I don't know what this tells me about the problem but I guess it answers the question of how the starter knows to start. I assume the voltage increases to 12v when I press the starter button.

Still confused
Cheers

 

[Keith Chapman]

Just a thought, you dont have any wires behind the starter motor cover that could be touching soloniod conections occasionaly and causing the motor to spin do you?

 

[TangibleSolid]

no loose or broken wires and no bad connections anywhere that I can find.

 

[Greg Masters]

I assume the voltage increases to 12v when I press the starter button.

Check it!!

Greg

 

[roddy]

I've checked my 1150GSA 2004 and with black wire connected voltage between chassis and wire 0v
take black wire off voltage between chassis and wire 12v this comes form the LRR coil,
when I pressed the starter button i measured 12v to the starter solenoid and to the otherside of the LRR coil, (though i can double check this later in the week)

so the voltage difference between the 2 points of the LRR coils is 0v (12v both sides) the starter relay sends 12v to the starter relay so it activates.

As mentioned the voltage is being applied between the LRR coil and the starter solenoid, if you can run the bike without the the LRR relay if the starter accidentally kicks in you know it's not the LRR relay, run the bike without the starter relay if the starter doesn't accidentally kick in you have narrowed it down to the starter circuit, after that your either replacing/checking wire sections or components or a supply via a failing diode on the clutch/side stand switch though I trhink most of these dioides go to ground ?, diodes can be checked quite easily using a DVM most have diode check function.

 

[TangibleSolid]

Hi Guys

The story gets wierder. I managed to replicate the fault (or at least it happened!!) yesterday in the garage and whats even better is that I had the voltmeter between the starter 'tag' and earth when it happened. As it happened the meter spiked to 12v which suggests to me that the starter is starting BECAUSE its getting 12v from the relay (or elsewhere). This turns my previous ideas on there head because the starter should start when it gets 12v, so I now don't think it's faulty.

So.... I'm back wondering about the relay, wiring or switch. I don't seem to be able to replicate the fault by bending or twisting any wiring from the switch unit to the multiplug and the switch seems to be switching as it should. I suppose its possible that the second relay could also be faulty but I am assured that it was working correctly when I borrowed it.

I must admit i'm at the point where I don't know which way to turn, I might even 'wave the white flag' and take it to the dealers. ( I will have to save up a bit though as i've been told local dealer is quoting £70 per hour labour plus parts and God knows how long it will take to trace an intermittant electrical fault )
Cheers

 

[roddy]

Right...... Had a look at the wiring diagram and I've a question

when this problem happens is the side stand down ? or has it happened regardless of side stand position ?

 

[TangibleSolid]

Now you mention it, always with the side stand up. I've never noticed it while the stand is down because the bike has either been actually running on the road or on the centre stand in the garage
Do you think this could be a problem?
is it possible to test the switch or at least exclude it from the circuit.

 

[Keith Chapman]

Hi Guys


I must admit i'm at the point where I don't know which way to turn, I might even 'wave the white flag' and take it to the dealers. ( I will have to save up a bit though as i've been told local dealer is quoting £70 per hour labour plus parts and God knows how long it will take to trace an intermittant electrical fault )
Cheers

Try a good auto electrician, should be cheaper than a dealer.

 

[TangibleSolid]

Just to let you all know, and for anyones future reference, I have found the problem (finally). Its the starter switch unit.

I got the digi-meter on to every connection and found that the Black/Yellow switched live coming from the switch had 12v ALL the time. My reading of the wiring diagram shows that this wire should ONLY have 12v when the starter switch is closed. Initally I found 12v at the relay (relay terminal number 4 ) which meant that there was either a fault in the switch unit and/or switch wiring, OR there was a short in the wiring loom from the switch multiblock to the starter relay.

By disconnecting the switch at the multiblock I did not find 12v at the relay so discounted a short in the loom. When I connected the multi- block back in (to get 12v from the ignition) the black/yellow wire from the switch tested 12v all the time on the switch side of the multiblock AND at the relay. Pressing the starter button made no difference to the 12v reading.

I then checked the same readings on a mates 1150gs and his did not have 12v on the relay UNTIL the starter switch was closed.
To me this obviously indicates a problem with my switch.

I don't understand why the bike was not ALWAYS engageing the starter but I am assumeing that although the switch is 'leaking' 12v there is NOT ALWAYS enough amps to trigger the relay.

The strangest reading (and the test that sent me down a shedload of 'blind alleys') was that with a continuity test across the switch it was showing ok, ie no continuity UNTIL the button is pressed. I am told that this is because the continuity test only sends a very small current through the circuit and this was not enough to make the switch 'leak'

I have now bought a new switch unit from the dealers (£250 inc vat, , of course it had to be the most expensive varient and it had to be shipped from Germany which took five days)

I've no doubt that someone with the appropriate skills could replace the actual starter switch in my unit but that person is not me! Also it occured to me that if one switch is knackered there is a reasonable possibility that others in the unit could be on there last legs (especially as I would have thought that the indicator switch does more work through its life than the starter switch).

Anyway I'm now back on the road and I'm also going to buy myself the Haynes 'Motorcycle Electrical Manual' book so that next time I will understand the principals a little better .

Thanks for everyone's help and advice, especially 'Roddy' and 'Ditchwater'

 

[(RIP) DitchWater]

Well done...

....F***ing well done.

I bet your pleased to be riding again; the weather's been great and am loving every minute of it.

Get out there and go for a cruise.

Ditch.