Bike didn't start - then it did!

[barry905]

First of all some background. WE are talking about a 2009 GS500F that is kept in a garage. It is completely standard and has been running well ever since I have owned it - since 147kms. It has now done 27800Kms.

Over the past week the bike has stalled on me a few times, perhaps 3 in all. It always immediately restarted nad went on its merry way, so I didn't worry about it. Then I noticed that the tachometer would drop to zero while I was riding at a steady speed, stay there forr a second or two and then jump back to the correct value. The engine would just run as normal, with no loss of power or any other symptoms of a problem.

Finally this morning when I tried to start it the lights came on as usual, the starter would turn the motor, but the engine would not start.I tried for about 5 minutes and then gave up.

About 7 hours later I tried again - and of course it started. First time as usual.

So my question is, does anyone have any idea what happened? My initial thoughts are either the igniter has an intermittent fault or there is a bad connection somewhere. So any thoughts on how to test the igniter (they're too pricey to randomly replace) or where to look for bad connections would be appreciated.

Thanks,

Barry

[sledge]

I would start by checking the ground connections and battery connections.

[The Buddha]

Yes specifically starting with the auxillary ground and the plug from the trigger coils.
Cool.
Buddha.

[qcbaker]

I also would check the battery itself. I once accidentally left my key in and in the "on" position all day. (Lucky no-one stole my bike, to be honest lol) Anyway, completely drained my battery and had to jump start the bike. On the ride home, the tach would sometimes drop to 0 even during acceleration. This problem went away entirely and hasn't come back since I properly charged the battery.

[sledge]

The tacho on the Fs is electronic and its very sensitive to low voltage. When it plays up its a good indicator that there is an issue with the electrical system.

[barry905]

My thanks to all of you that replied. Upon checking I found that the battery connection was loose and this might be causing my issues. The only problem I have with that solution is that if I can get enough power from the batter to run the starter motor motor, the plugs should spark (I thought).

However, I will find out in the morning. After tightening the connection, There was not enough juice in the battery to start the bike, so I have been charging it overnight. So hopefully I can ride to work tomorrow and not take the car!

Once again, thanks to all.

Barry