Battery or Solenoid?

ghiribizzo said:

More than likely a possibly that the starter relay is on the way out. You press button but maybe not enough 'oomph' to excite the motor.
Try a multimeter at the end of the exciter wire + frame ground. You know what is available at the battery terminals, but when the bike is in the state ready to start, i.e. all normal circuits on, does it have enough? Also, on bikes where the headlamp is on, does the lamp still go out when the button is pressed? If the head/tail lights stay on due to a faulty relay it can rob the 'potential'.
An old Guzzi trick - a spade terminal + 4" of wire to fire up reluctant starters but BMW's have the motor hidden away...

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ghiribizzo said:

If you can identify the relay, dependant on bike model there may be another on it somewhere that is exactly the same. A bit of careful substitution of parts might just confirm things before you go to BMW/Bosch etc to buy one.

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Welshman said:

I have a puzzling one, I assume battery, but maybe someone knows better, loose magnets etc?

1. Does not start first punch, but does on second?
2. Had battery tested, they say its good my multimeter shows 13v and there load tester says good?
3. Starts with jump leads on aux jump points

Any hints? Oh yeah, its a sealed lead acid battery, not really suited for a high draw application, but the previous one was good for a couple of years in this application.

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rudiemoto said:

get a earth jump lead fit one side to - on batt and other on starter housing then push button ,if it starts the earth lead under battery tray is loose

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Welshman said:

I just put my Multimeter across the starter, 13V then when I punch the starter she drops to 6.5V think I have my problem

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