running rough and backfiring after cold weather

[Alexander94]

Good afternoon all.

So icm having yet another problem (i don't seem to have much luck...)
After leaving my naked curvy for about a week, starting it a couple of times but the battery didn't like the cold, and just now I went out to do some tinkering (I'm treating her to some new LED indicators and adjustable levers)
I got her started after a bit of a struggle just to find that it was backfiring so I went out for a quick ride to see if it was just needed some breaking in after the cold.
At low revs it was juddering and in higher revs there wasn't much power.

Anyone else encountered this problem or Anyone know what the problem could be? I need to get to work on my bike tomorrow so it's a bit urgent...

[maviczap]

Sounds like wet front plug syndrome?

Spray some WD40 into the front plug hole & cap.

Do you have a Fenda extenda?

[Alexander94]

Thanks, I'll give that a go.
no... I had one on my old curvy but my "new" one doesnct have one and I forgot to take the one off the old bike

[maviczap]

Been riding in the rain much?

[Alexander94]

Yeah. It's been quite rainy but the bike's run fine until I stopped using it a week ago to take the train to work because of the snow and ice

[Alexander94]

I'm looking at fenda extendas now ;)

[Alexander94]

Thanks again for your reply. I've just been out and sprayed the plug caps and holes, she started straight away and sounded right. I can't believe I forgot about doing that! I feel rather silly...

[maviczap]

Ah well an easy solution, sometimes you can overlook the obvious

[andy1472]

I had that problem 4 weeks ago.
It took me ages to find out that the brown wire that runs from the rear lights, to the front lights and then splits up to the ignition unit was rotten. I noticed someone had opened the wiring loom tape cover with a razor blade in the past and caught the wires underneath. That was rotting a long long time until it couldn't supply enough voltage to the ignition and then in turn back into the coils.
While I was there I did a resistance test of the plug caps and found them to be double the resistance what the manual specifies is allowable. Rewired, brand new HT cable, new coils, plug caps and plugs. Oh and the intake rubbers where leaking too which was causing back fire and after fire. To finish it off I used a carbtune kit to re balance the carbs as they were 3/4 difference on the gauges out against each other. All sorted now and she runs so nice. I did the work myself. I never trust garages. I'm training to work in one lol.