Clicking sound on starter solenoid

[cpazambrana]

Hi to all,

I recently bought a 1976 R60/6. The bike runs well and from cold, she starts well. However, after warming, say, a ride of 20 or more miles, if I turn the engine off it would not start when I try to. All I hear is a clicking noise from the solenoid. I have clean the connections at the right handlebar switch, the starter relay and the other relay that is located on the right side of the frame. Battery is only 6 months old and works well on my other Airhead, a R80RT. When the clicking sound occurs, the battery goes down from 12-8-12.9 to 12.4-12.5, not much of a change. I checked the negative cable from the battery to the ground speedo screw and seems to be good. If I let the bike to get cold after a ride, then she starts ok again. If I tried to do it while she is warm, I only get the clicking sound.

I haven't clean the connections at the starter yet. I have read numerous threads but none seem to be the exact same problem as me regarding that this happens only when she is warm.

What could be wrong here guys? Any help will be appreciated.

[RPGR90s]

My first test would be to verify what is clicking. The starter relay on the left side of the frame rail (under the tank) or the starter solenoid itself.

I would pull the starter cover off the bike and remove the small black wire that connects to the starter. This is the 12v signal that energizes the BIG starter solenoid when you press the starter button. If you hear the click with this wire removed, then one can assume that the small starter relay (under the tank) is at least moving mechanically.

I'm sure others will chime in with more tips.

[jagarra]

I am thinking to have a load test done on battery, most times when the solenoid on the starter clicks like that it is an indication of not enough amps to engage the starter. I would also check your positive cable from battery to starter, corrosion can reduce current going to battery. I have seen corrosion in the first couple of inches on the positive side, just past where is connects to battery.
One thing I have noticed when coming back from a ride and hooking up the float charge to bike again, it always goes to a charge even though I have been riding, that might explain why it clicks when hot, battery still not fully charged.

[cpazambrana]

Thank guys. I went all the way and took off the starter solenoid and clean all the electrical connections. There was a lot of corrosion and even a loose cable. I rode the bike today and she started every time. Sometimes its the simplest thing. Now I'm just left to check the front brake sensor, adjust valves and the turn light indicator which is not working. The signals work but not the indicator in the dash. Any suggestions with this?

[RPGR90s]

The turn signal relay is in the headlight relay so you can start there, but logic dictates checking the bulb in the instrument cluster first.

[cpazambrana]

The turn signal relay is new as I lost the old one when I first checked this. The bulb is also new. The light turns on initially when I push the turn signal switch. It flashes once and then goes out completely.

[Rob Frankham]

The turn signal relay is new as I lost the old one when I first checked this. The bulb is also new. The light turns on initially when I push the turn signal switch. It flashes once and then goes out completely.

This is almost certainly a defective relay. It's a common fault with the 4 terminal relays used on the /6 and /7 machines. The solution is to:-

a) Replace the relay - simple but not cheap. You don't have to use the OEM BMW relay, many generic aftermarket 4 terminal relays will do the job provided the terminal connections are compatible.

b) Make a simple work around that will allow the use of a generic 3 terminal relay (actualy, if your existing relay is working satisfactorily apart from the repeater, you don't need to chage it at all). Here is a 'how to' I worked up earlier...

The 'correct' solution would be to replace the relay... but... there is a much cheaper solution if you are willing to play with a soldering iron, a couple of diodes and a few bits of wire.

I am going to refer to wires here by their BMW colour code. This isn't essential, as long as you know which wire is which.

Take two diodes. I would suggest IN4002 but virtually any recifier diode will do the job. Each diode is a small black cylinder with a white (or silver) band at one end and a lead from each end.

Place the two diodes together and wind the two leads from the two banded ends together. Add a length of Black/White wire and solder them all together.

On one of the other leads, solder a blue/black wire and on the other a blue/red wire.

Make sure all of the leads and joints are insulated from each other. Ideally use heat shrink tubing but insulating tape will do the job.

Add a male spade connector to the black/white wire and a female spade connector to each of the blue/black and blue/red wires.

Inside the headlamp shell, remove the existing black/white wire from the relay and connect it to the black/white wire on your new assembly.

Connect the blue/red and blue/black wires to spare terminals marked R and L on the circuit board in the headlamp shell.

That's it... Robert is your fathers (or mothers) brother.

I've worked up a very quick diagram of the circuit below.

Indicator Pigtail.jpg (40.91 KiB) Viewed 873 times

Rob

[RPGR90s]

I agree with Rob,

Years ago I had this same issue on '74 R90s. Turn on signal, the indicator light on the dash would flash once but the signal lights worked fine.

I traced it to the relay. Specifically, the output on the relay that feeds the indicator light on the dash. A new relay solved the issue. And that was many, many years ago.

[cpazambrana]

Thanks guys but as I said, the relay is new and is the Enduralast that Euromotoelectrics sells. Now that I note, the description of the relay in this site says as follows:

"NOTE: The relay has a "bulb out feature" which means that when one of your bulbs is burned out (or you have a bad ground), the remaining turn signal (on the burned out side) will continue to blink, but the dash indicator will blink once, then stop."

Now I wonder if it is a bad ground (given that the bulb is also new) and the relay is doing what is supposed to with it's "bulb out feature".

[jagarra]

If I remember correctly the turn signals are grounded via the housing to ground, so there may not be a ground wire coming off the socket. Maybe cleaning where the housing touches the stocks will solve the issue. You could verify it's a grounding issue with a long wire touching the outside of the socket to a frame or battery ground to see if by passing the housing ground solves issue.