Moved: Cyclinder Issues, help greatly appreciated!

Ok so, for the last few days my K6 has been running a bit wierd, at high revs you could hear one of the cylinders occasionally misfire and at low revs (idle) it runs only on 1 cylinder at <1000rpm then stalls.

So after reading alot of posts on here, thought it must be water in the plugs, so removed both, they were both black and stank of petrol so gave them a dry/clean and put em back....no difference.

Went to bed.

The morning came, and me being an optimist thought the bike fairies might have been out during the night it might now work.

No change.

Still thought the problem was with the plugs so went to halfords, bought some shiny new ones, fitted them.

No change.

About half hour later went to start the bike again and now it wont even start. Getting pretty annoyed by this point, I pushed it down to my nearest garage which was a Yamama place about 2 miles away in the baking sun. As my Suzuki dealership is closed on wednesdays and I needed the bike fixed for today.

Garage told me my battery is screwed and I need a new one. As I was in a hurry to sort it out I agreed, £45 for the battery i was told. I was told the battery would be charged and fitted by 4pm. By this point I'd decided there was no point in going to work on public transport so called in to say I was having somekind of breakdown .



4pm: Walk back down to the garage, told it cost £78 (£49 battery, £2 labour...nice.

No change.

Took the bike out for a thrashing to hopefully clear out some of the crap near the plugs....You guessed it, still no change. Had another look at the NEW plugs, front is black and sooty, back is black and petrolly (the garage told me it was the back that wasn't firing properly)

Luckily my dad's lent me his bandit till I get it sorted

Sorry for the long post but my questions are:

1) Does anyone have any idea what could be happening here and if so how can it be fixed?
2) When I take the bike to the dealership at the weekend would the work be covered by warrenty? (bike under 2 years old)

Any Help gratfully received

Chris

Have a looka at your air filter and perhaps give it a clean.

also check the coil

I'll check the air filter, not sure what a coil is let alone how to check it lol (duh sorry).

Just rang up the dealership to warn them i'm on my way. They mentioned the coil, also said they'd been having alot in because of the new biofuels being integrated are causing a fury deposit in places...

So is the coil easy to check/change..?

Cheers for the help so far!