Starter Issues

[Oldmans Trophy]

Hi everyone
Cleaned my 1200 mk 1 Trophy today as it was in need after a rally. It ran fine 2 weeks ago. On starting it seemed intially to be low on battery power (couldn't have been though as its been on optimate) but then it fired up as usual after a couple of seconds.
Gave it a 3 mile run n returned home. Turned off ignition after going to Neutral n side stand down but the starter motor came in so I turned ignition back to on. I had to physically disconnect the battery.
Even with Kill switch to off and the side stand down the starter cranks when I reconnect the battery.
Any ideas?

 

[atomsplitter]

You have a short to ground thru the starter ciruit. Open the right hand starter switch housing and spray in some contact cleaner. Likely have an electrical bridge in the switch that's causing it.

 

[Oldmans Trophy]

You have a short to ground thru the starter ciruit. Open the right hand starter switch housing and spray in some contact cleaner. Likely have an electrical bridge in the switch that's causing it.

Many thanks for the help ...... I'll check on that this evening.
Since posting I had a look online and read something about the solenoid getting stuck on closed - do you know if that could result in the starter motor engaging despite kill switch being off/side stand cut off and the key being removed from the ingition?

 

[atomsplitter]

Only if the return spring was broken. A solenoid usually requires the power to the coil to draw in pinion gear to flywheel. No power, no actuation. Power off spring should disengage flywheel pinion.

 

[Oldmans Trophy]

Only if the return spring was broken. A solenoid usually requires the power to the coil to draw in pinion gear to flywheel. No power, no actuation. Power off spring should disengage flywheel pinion.

I opened up the starter housing and everything seemed as it should be .... very clean. My contact cleaner was at work so I used some ordinay Wd40. I'll bring my Wd 40 Contact cleaner home tomorrow n try again as my standard Wd40 made no difference.

 

[atomsplitter]

You might have a stuck relay as another possibility of what's causig the issue. The starter button on the handlebar actuates a relay to put battery power directly to the starter motor.

 

[Oldmans Trophy]

You might have a stuck relay as another possibility of what's causig the issue. The starter button on the handlebar actuates a relay to put battery power directly to the starter motor.

Mmmmm ..... thanks for that suggestion. As the starter motor appears to cease to operate when the engine is running doesn't that rule out a stuck relay?

 

[atomsplitter]

Mmmmm ..... thanks for that suggestion. As the starter motor appears to cease to operate when the engine is running doesn't that rule out a stuck relay?

Not necessarily. Try a different relay (swap out) and see if it still spins the starter motor with a different relay (process of elimination). Looking at the schematic the starter button actuates the relay to put only + battery voltage on the starter's terminal. The starter's case is ground so the relay only puts power from the positive side of the battery to the starter. Either the relay is bad, or there's a bridge in the start/stop switch on the handlebar closing the relay to spin the starter.

 

[Oldmans Trophy]

Many thanks for your very detailed reply ..... sounds like a job for the weekend as I'm working all week.