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1200 LC question

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6 November 2018 - 1:45pm
@lanticbiker
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Joined: 2017/10/16

Hello all,

I fell over this weekend in a most frustrating manner. That's another story..
However, I struggled to pick the bike up. It lay on its side for about 30 seconds with the ignition on and then another 10 minutes with ignition off.
When I finally picked it up, dusted myself off and calmed down and tried to ride off, nothing happened when I hit the starter button....
I tried again and a couple of clicks ensued. Third time it sort of fired but there was a loud clank from the engine, after which it cut out after about 2 seconds.  I gave it ten seconds and tried again...
Finally, it started, coughed out some dark smoke which cleared after 10 seconds and since then it has run like a train again. No further issues either running or starting.

So..My question is this: What happened? Why did the process start with no reaction at all and then gradually improve in steps until it started?  Is there some fiendish software which first empties the unused petrol from the cylinder before it starts? Or did I just have to get the motor to tick over to clear the fuel and keep trying until it started?

Keen to hear an explanation.

Cheers

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  • 322 reads
8 November 2018 - 6:40am
#1
Charles Oertel
Charles Oertel's picture
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Joined: 2007/04/14

It is unlikely to be fuel in the cylinder, because without power the fuel injection system is shut off (as is the fuel pump).

My first thought is a loose battery connection, but then the bike would have been dead altogether.

What does happen when the bike is on its side is that oil seeps into the pot, especially around the tappets. This will account for the smoke.  It may also account for the other symptoms.  I tend to leave my bike standing upright for a while after a fall so that the oil can seep back down.

The starter motor failing to crank the engine is sometimes a symptom of a loose magnet in the motor jamming it up.  This used to be an issue in the older 1150s, where they were glued into the motor and the glue eventually failed.  Perhaps the fall or some other event has loosened or broken a magnet.  The problem is intermittent - so if it happens again for no reason have the starter motor checked out.

Committee: Webmaster / Ride Captain

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8 November 2018 - 11:30am
#2
@lanticbiker
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Joined: 2017/10/16

Thanks. It has never done it before or since so I am assuming it has to be either fuel pumped into the cyclinder in the 15 or so seconds the motor was off while the ignition was still on, or, as you suggest, oil. Since it was black smoke, not blue-black, I am leaning towards fuel.

 

Thanks again

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