Starting Troubles

[Steviescumbag]

Good Day,
I last rode my K75 a few weeks back and its started and worked beautifully. I recently went to ride and it does not want to start. The starter relay buzzes when I try to start it. i give it a couple smacks and even opened it and it looks in good condition, it is not welded together.

Could the above methods be a solution to this problem or do you think it is something more.

Mind you, i currently do not have a cluster (speedo) connected so I do have to pull in the clutch to start it.

I tried starting it with the 4 way flasher disconnected and still a buzz with no start.

I will follow the directions above! but if this sounds like something more specific. please let me know!

[Laitch]

My first impression is that the battery has discharged but is not dead yet. What is the resting voltage and what does it read when attempting to start? Because you seem to be engaged in some modifications, there also might be problems with power and ground connections.

[The Mighty Gryphon]

My first impression is that the battery has discharged but is not dead yet. What is the resting voltage and what does it read when attempting to start? Because you seem to be engaged in some modifications, there also might be problems with power and ground connections.

+1

[Steviescumbag]

The resting voltage reads 12 .

I disconnected the starter relay connector and the buzzing stoped when I tried to start it.

The starter relay connector voltage dropped when I tried starting it.

[Laitch]

That battery needs to be charged up. Should be above 12.6V. Get it there then try it again. If the battery is faulty, it might not hold a recharge for long.

[Steviescumbag]

So I charged it up. Even had it connected to my car battery and tried starting it up. But the starter relay still buzzes when I press the starter button. I don’t know what else it could be. I feel it is something so simple but can’t figure it out. I cleaned all the contacts with contact cleaner under the tank.

All the lights are on , blinkers work, head light works. But when I try to press the starter button the lights cut out.

Do you think it can still be the battery and I should get a new one? Or would the connection to the car be sufficient enough to start it .

[frankenduck]

But when I try to press the starter button the lights cut out.

That's supposed to happen. The load shed relay kills power to the headlight and other stuff so that you have more power to the starter motor.

[Steviescumbag]

Okay right. Don’t know what it could be then.

[The Mighty Gryphon]

The lights should go out when the start button is pressed, that is the normal function of the load shed relay.  That relay is energized by the voltage drop across the starter motor in a strange circuit that only a BMW engineer could come up with. 

That tells me that your start relay is trying to close and send power to the starter motor.  Have you opened up the start relay and checked the contacts to see if they are burned?  That could be limiting the current to the starter motor.  Have you pulled the starter and checked the brushes and cleaned the commutator?  Bad contact between the brushes and commutator are known to cause problems when trying to start the engine. 

Have you cleaned the insides of the start button on the right handlebar.  That is another known problem area if neglected.  Same goes for the ignition switch on the handlebar pad.  There are instructions posted here on cleaning it.  I've had problems with mine on two occasions and some of your symptoms sound like what mine was doing.

[Steviescumbag]

Thanks for the replies boys.

I opened the starter relay and it looks in good shape. I cleaned the ignition switch and the starter button.
If all it takes for the starter button is open the right hand side and clean the back of the button.

I’m going to roll back the bike and try to clean the starter brushes.

[frankenduck]

Did you take the starter button out of the combo switch assembly and clean the internal contacts?  When doing this have a shoebox or something below to catch the little springs that might fall out.

Another thing to try is to put a large screwdriver across the two terminal bolts on the top of the starter relay. That should cause the starter motor to turn. BE ABSOLUTELY SURE THAT THE BIKE IS IN NEUTRAL BEFORE DOING THIS. (Or at least on the center stand.) The key does not have to be on.

If the  starter motor turns when you do that then the issue is probably with the relay.

[daveson]

I'm thinking your not getting power to pin 86 (black/yellow) or your not getting earth at 85 (brown/red) Maybe your not getting good earth. An earth jumper wire to 85 might eliminate the buzz and allow the bike to start. If so, earth needs a look see.

No luck?  Maybe you don't have good power. With a jumper wire from battery positive to pin 86, your bike might start (with the start button pressed, of course)

[Steviescumbag]

Thanks again guys. Your input is super helpful. the first thing I did from all your advice was put a screw driver connecting the two bolts on the starter relay as @frankenduck mentioned. There were a few sparks but the motor did not try to turn.

Could this be a grounding issue than? But all my lights work.

Could you also give me more insight on what and where are pins 85 and 86.

[Laitch]

I’m going to roll back the bike and try to clean the starter brushes.

Did you do this? If you did, describe how you did it.

Did you take the starter button out of the combo switch assembly and clean the internal contacts?  When doing this have a shoebox or something below to catch the little springs that might fall out.

Did you do this?

[Steviescumbag]

I did not because I figured if it doesn’t start by bypassing the starter then it can’t be any of the other points. Tell me if I’m wrong!

I’ve seen though from Johnny that to clean the brushes all you did is : in 3rd gear or higher , pop the clutch when rolling to backwards. And do it a few times.

[Steviescumbag]

Boyssss.

I’m fucking stoked. It started and the problem was sooo simple.

I cleaned the the ground wire from the battery at the point it connected at the gear box by the left peg. Give it a good clean with contact cleaner and it started in no time. I reckon that this is a place for gunk to build because it is exposed, and near the ground.

Let’s gooo.
Thanks guys.

[Past-my-Prime]