Totay I tried fitting a new 12v 30amp battery to my 1984 K100 RS. I connected the positive (ground) terminal first. When I went to connect the negative I singed a large peice of my palm and the negative terminal part-meltedas I went to slip the bolt through it! I assume this must be a short somewhere, as the ignition key wasn't in or on. The bike was in daily use until a few months ago with no sign of electrical problems. Any ideas guts, or have I missed something blindingly obvious?
Chris

POSITIVE Ground?????

Mines Negative ground so was my 85RT
I think you got yer terminals mixed up
or maybe you were supplied the wrong battery with terminals
in the alternate positions
Its happened before
Mine has its terminals facing the front of the bike and the
positive terminal is on the left hand side
This goes to the alternator etc
The negative terminal is on the right hand side and connects to the
screw on the left of the motor, below and in front of the battery

Ooops, doesn't sound good. Above is right 0 ground is negative, the + is + .

K's are always negative - to ground/frame the + (positive) goes to the battery. You will need to look to see what if anything you have blown up, you may be lucky.
Let us know what you find.
Regards,
K-BIKE

Thanks guys, I appreciate your help.

When I disconnected the old battery several weeks ago I forgot to note the connections. Before fitting the new battery, I checked the handbook and the internet to find out if is negative or positive earth - but couldn't find the answer. So I decided to be guided by the position of the leads (because I new which way the battery had been in), this was my mistake.

I have just reconnected the battery correctly and checked the main fuse board (nothing blown). The bike turns over a treat but is not starting (has plenty of fuel). I would be grateful for any ideas, guys. Are there any other fuses that I need to check?

Chris

not aware of any other fuses Chris
and not familiar enough with these bikes to know what may result from the battery
being cross connected
Hopefully nothing expensive has been damaged
If you give the starter button a quick stab can you hear the fuel pump whine?
On a few occasions whilst tinkering I've forgotten to reconnect the 4 way connector to the tank and had
the motor turning over and over with no result until I remembered to plug it in again.
A badly connected plug on the control unit under the seat can give give similar symptoms too
I'd whip off a plug cap and check for sparks as well

Also, I know the K's do tend to get the weather in the connectors so would suggest
you open check and clean as many as you can
Some Electrolube or similar is useful here.

Looking at the interractive electrical diagrams (under the "battery draining tab), the only components getting power from the battery when the ignition is OFF are:

Alternator
flashing unit (this is for the 4 way flashers)
Alarm system
the clock
load shed, fuel injector and starter relays. (only the power lead is powered and reversing the battery polarity should not have any effect)

I cannot see any major electronic components that could be affected by reversing the polarity AND not turning the ignition ON.

Thanks guys, I appreciate your help. Will persevere.
Chris

Kickstand safety relay? Is the bike in neutral, kickstand up when trying to start? Haven't had my K long enuf to comment since it's currently in a million pieces, but my R1150RT will spin over all day long and not start if the bike is in gear and the kickstand down.

I dont think the K's have Kickstand switches
not aware of one on mine and dont see any in the wiring diagrams
I have a dim memory of some bloke who had a K that would run when on the
side stand but cut out when he put it upright
?
Dont know if he ever got to the bottom of that one.

I have a bad feeling about this one and remember a very similar post that required a new ECU.

But before going that far we need to know if you have sparks and fuel.

1990 K100RS definitely has a sidestand microswitch.

I suspect from the big flash the alternator diodes and regulator are probably toast something drew a lot of current.
Regards,
K-BIKE

Thanks Phil. I work away during the week, so won't be able to look at it again until next Saturday. I assume there is no easy way to test the ECU (?)

I also have an R1200C which does have a "stand down" sensor (but I don't recall the K100 having one). However, when I have tried starting the bike I have sat on it with the stand up.

obsidianskies wrote:Thanks Phil. I work away during the week, so won't be able to look at it again until next Saturday. I assume there is no easy way to test the ECU (?)

I also have an R1200C which does have a "stand down" sensor (but I don't recall the K100 having one). However, when I have tried starting the bike I have sat on it with the stand up.

Well that does raise another hopeful point and depending on the year of your bike you may have a sidestand switch which, in K-Bikes case and another post I recall, allows the bike to crank over but not fire.

Heres hoping,

With my 1990 K100RS 16 V if the sidestand is down I can crank as long as the battery can supply power and no start not a cough nothing, flip the stand up and vroom as they say DAMHIK! Doh!
Bit like the time on my Goldwing when I accidentally knocked the emergency stop switch to the off position with my glove and could not work out why it would not go.
Regards,
K-BIKE