Hi all. 
The other day a delivery chap saw my bike in my garage and after a discussion about the K bikes, I used the first stage of the "choke but not a choke " lever and  started the motor. As she had not been  run for a week or so, she took an extra couple of  turns and then fired up. I then switched her off after ten seconds or so. 
Today having got all my gear on  for a ride, she turned over but would not start.
Hmm great I thought.
She also dumped fuel on the drive from around the rear cylinder No 4
The battery was checked and showed 11.98 volts not ideal but enough I thought.

I took the plugs out and all four were wet, so fuel was okay.
I dried them, refitted and tried again , but again, no response.
Plugs dried again and checked for spark, and all four zapped. 
Removed fuel pump connector, plugs, and spun motor to dry the cylinders.
Refitted some old plugs I used , and spun the motor with the fuel pump disconnected, and she tried to run. 
Connected fuel pump connector and with a wot throttle she  eventually cleared and ran fine afterwards.

so. 2 questions.

1. Why the initial fuel dump.  I have no obvious fueling issues /  leaks and  she runs strong and  economical.
2. As my Coolant temperature sensor is original, could it be putting excess fuel in when cold , meaning I inadvertently flooded the engine when I ran her for just a moment.


I will change the battery at some point 
Has anyone else come across this ?
Thanks 
Bob

audibob wrote:Has anyone else come across this ?

It's not an unusual tale, Bob. I think in your case your battery needs more output and when it has it, your bike will start.

You can burn off the fuel in the drive to amuse the neighborhood children.

Was the tank overly full of fuel? 

There is an air vent line that exits from the tank bottom that may have functioned as an over-flow to dump some fuel--the hose runs down the right side frame toward the rear, or drips onto the air filter housing and runs off near the #4 cylinder if on the side stand.

Fuel coming out of the headers at start-up is typical of the temp sensor losing its earth contact. Maybe a bit of corrosion around the sensor thread. Test the resistance on FICU pin 10 & 13, particularly if it happens again.
You could also check/clean the FICU plug contacts or the plug can be a little loose. Loss of continuity on one of those pins will have the same effect.

Thanks for the replies.
The fuel dump saved me time weeding my drive, and the fuel tank was only half full.
I have never  seen an overflow even when filled to the brim, so Holisters comment about the Coolant temp sensor seems right, as I have noticed the green muck around its threads. It is 27 years old after all.
I intended to replace it along with the sensor for the Temperature Gauge.
A new Thermostat will go in during December, along with a nice set of 1100 throttle bodies.
I will check the battery voltage regularly ,and the Alternator output, and replace as necessary.
Thanks again .
Bob

audibob wrote:along with a nice set of 1100 throttle bodies.

Don't forget to advance the timing by six degrees when you do that. Makes a helluva lot of difference!

Thanks Dai.
I will advance the timing first to see the difference before fitting the bigger throttle bodies, cant wait ......