Misfiring on startup? Calms down after a while.

The wiring loom on your bike has a negative wire (ground) going to all devices that need it and they are all then connected to a common point on the left hand side of the crankcase behind the rear cylinder. The negative from the battery is connected to a stud on the other side of the crankcase.

If something looses its negative connection then it will be continuity in a wire, it might happen that a couple of devices downstream of a break in the loom might be affected. If you have a bad ground connection it will affect the whole bike, IMO and due to high current requirements I think will show up in poor starting with a slow or non existent starter motor.
 
Thanks Andy. Ironically, the bike has never failed to start. Admittedly, when I press the starter button it hesitates at first, but then turns over with gusto.
I put the hesitation down to having to "wake up" the lithium battery, I say this because the only time the starter motor hesitates is on a cold start where it needs to turn over a cold motor, any other time the starter turns over quickly.
So starting the bike really has never been a problem, this all came about when I realised after a long lay-up in a damp garage, the cold running initially would misfire a bit, but once warm, would run as normal.
BUT, and it's a big but, I hadn't run it at that point two-up and with loads of luggage, that's when the lean running once warm really showed itself as clearly it wasn't getting enough fuel under duress to feed the torque, and I had to keep dropping gears to stop it shaking like mad.
I'll check out those manuals, thanks.
 
UPDATE TODAY:
I've now taken out the plugs that Seville HD put in with the new air filter.
The photo of them on the dustbin show the model of plugs, also the Iridium ones I had in before my trip (I think these might be fake NGK plugs as the aluminium ferrules I'm told shouldn't be unscrewable, but they are, I don't know if that's an accurate sign of their provenance).
The other photo shows the Seville plugs on the right and the Iridium on the left.
Interestingly, the Seville HD plugs have a model number I don't recognise, plus the printing of their name is off kilter on one plug-another sign that allegedly indicates fake plugs.

Far more interesting is that the Seville HD plugs don't look that white, so now I'm wondering if the fact that the bike may have been overweight, 2 people plus loads of luggage (I suspect it may have been 30KG over) might have been the reason for not running right, BUT it didn't explain the misfiring on cold starts.

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Looking at the photos closeup now, I see that the HD plugs have very few deposits at all, would that indicate lean running?
Also could someome comment on the suitability of the model numbers, Iridium, and HD?
I'm going to get someone to check the TMAP and oxygen sensors as I can't imagine what else could have caused the lean running.
 
6R12 is the HD part number. Those plugs look okay to me.

It seems in the past plugs were a very light brown colour but being white ish with nothing stuck to the insulator and no pitting is okay.

Dave the guy at Northants V-Twin has only ever had problems with non HD plugs. For a different reason my partner took her machine to him and he kindly swapped out the NGK plugs.
 
Andy from Sandy said:
6R12 is the HD part number. Those plugs look okay to me.

It seems in the past plugs were a very light brown colour but being white ish with nothing stuck to the insulator and no pitting is okay.

Dave the guy at Northants V-Twin has only ever had problems with non HD plugs. For a different reason my partner took her machine to him and he kindly swapped out the NGK plugs.
Click to expand...
Good to know Andy, I'll leave them in, and as you say, whitish with no pitting ok.
I'm now wondering more than ever if it was just a weight issue.
 
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