my dredded electrical problems

well, I though all my electrical problems had gone away.
but alas, no.
Instead we've had unusually nice sunny weather meaning that the bike has behaved itself.
now back to the damp and the electrical systems are playing up again.
so where to begin...

my story:
reg/rec blew up in the summer, changed and it's working fine 14v across the terminals at 5k rpm with lights on and indicators flashing.
(i hope i dont need to bold that)

headlight blew on the right side not too long ago, i've replaced the connector with a nice new one and insulated everything, headlights working fine again.

The problem:
when the weather is damp (ie been/is raining) you can turn everything on just fine, however the second you hit the starter button all the power is drained from the bike and suddenly it refused to even turn over, as if the battery is dead, infact this act almost kills the battery as well so it's definately "bleeding" power somewhere.

I've checked the obvious cables and everything is looking fine, i'm thinking that either:
1) the starter moter is on it's last legs and about to die.
2) there is an earth fault somewhere meaning that the power is being sapped from teh bike before it even gets to the starter. - Short.

I'm inclined with the second possibility but what cables to i need to check and where exactly?

Thanks all.

Collis

You say the bike's electrical circuits die when pressing the start button. When you release the button do the lights come back on? can you sound the horn?

If so then it would boil down to a bad connection to the starter motor, either earth or live feed, remember it goes via the starter relay which also must be low resistance and functioning correctly.

If the battery does not recover and bring back the lights and horn then it would point to a battery fault.

A faulty starter motor can exceptionally draw too much current or prevent itself working due to internal fault but I would make sure everything else is right first as this is a much lower probability.

My thoughts are that the battery will be the culprit.

Have you checked the connector at the starter motor, i had a similar problem and it turned out that the connector was full of crap. If you put the lights on then turn on your indicators and press your horn do the lights on the dash die

Originally Posted by Rob969

Have you checked the connector at the starter motor, i had a similar problem and it turned out that the connector was full of crap. If you put the lights on then turn on your indicators and press your horn do the lights on the dash die

didnt know there was a connector at the starter.

my problem only occurs when it's wet so i'm thinking that there is a fault with an earth line somewhere

You could selectively wet different areas of the bike

[MJC-DEV]

I've had something similar where it was the start switch itself that was full of corrosion green/black crap which became conductive when wet/damp. Pressing the switch caused a short circuit instead of sending volts to the starter.

Originally Posted by warmshed

You say the bike's electrical circuits die when pressing the start button. When you release the button do the lights come back on? can you sound the horn?

If so then it would boil down to a bad connection to the starter motor, either earth or live feed, remember it goes via the starter relay which also must be low resistance and functioning correctly.

If the battery does not recover and bring back the lights and horn then it would point to a battery fault.

A faulty starter motor can exceptionally draw too much current or prevent itself working due to internal fault but I would make sure everything else is right first as this is a much lower probability.

My thoughts are that the battery will be the culprit.

Any details?

Originally Posted by warmshed

You say the bike's electrical circuits die when pressing the start button. When you release the button do the lights come back on? can you sound the horn?

If so then it would boil down to a bad connection to the starter motor, either earth or live feed, remember it goes via the starter relay which also must be low resistance and functioning correctly.

If the battery does not recover and bring back the lights and horn then it would point to a battery fault.

A faulty starter motor can exceptionally draw too much current or prevent itself working due to internal fault but I would make sure everything else is right first as this is a much lower probability.

My thoughts are that the battery will be the culprit.

Hmm .... But the OP implied that when the weather is dry he does not have these problems -- this to me would imply that the battery is fine, and that there is a short somewhere else on the starting system ..

OP -- in the damp wet weather have you tried NOT switching lights etc on before hitting the start button ?? does it start OK or still sound like its dying ?