petrol contamination

well.....i usually ride the sv650 but it started loosing low end power. thought it was the carbs, so stripped them, sorted out the choke cable, re-fitted it, and stil the same. while thats been off the road i've been riding the 1200 bandit to work. carried on working on the sv, checked the plugs, fine, ordered some new jets as it needed to be done to account for the mods, and also shim the pilot needle.
now as i sais, ive been riding the bandit to work, and had to fill up last night. heading home, stopped at some lights and it just cut out! tried starting it, and it would misfire on certain cylinders, and run really rough. could barelly get going. so i stopped for a bit, started it on prime, then changed to on, and managed to jsut about get home. brought some plugs, changed them, started it up and was running fine. couldnt take it for a test ride cos it was raining. got it out the garage this morning, and again, while starting up it was misfiring! this really got on my tits! caried on anyway, and cured itself! im worried its not going to run right when i leave to go home, but i will deal with that later.
But it hit me earlier..that both bikes were filled from the same serice station. just wondering if the petrol could be dodgy, and be mucking around with the bikes. anyone had this problem or could shed a light on the situation?

[Mr Speirs]

Didn't fill it with Diesel did ya???

sensible answers please!

[SoulKiss]

Originally Posted by riktherider

sensible answers please!

Petevtwin is up to 3 recorded Diesel fills - so not that silly really

[yorkie_chris]

Could be, what did plugs look like? Is the bandit modded?

[punyXpress]

Carb icing?

bandit has only got end can on really, and replacement headers, not a proper akrapovic as such. Plugs looked and sparked ok bar 2, so i changed them anyway.
sv had after market pipes on, de-snorkled filter, and also recently had plugs changed.

Bad fuel is always a possibility... My worst case was a tank of fuel that stopped the bike within 2km of filling up necessitating a full strip and clean of the fuel system. The recovered fuel (~20l) had a dozen or so fist sized globs of muddy water floating in it. The operator denied any problem at the time, but the storage tank that it came out of was replaced a short time later. Not too many people, operators included, give those tanks too much thought until there is a problem. Condensation is an issue with all tanks. A couple more instances of watery fuel had me carrying a small water separator/filter.
Also, a couple of percent methylated spirits can help to clear moisture from a tank - water and fuel doesn't mix, metho and fuel does, as does water and metho. The other alternative is draining the tank if the fuel is suspect... and going elsewhere to buy your fuel.

Cheers

[embee]

I'd say it's a distinct possibility.

I've certainly had one instance in the car of bad fuel from a particular station I don't normally use. The car is pretty indifferent to fuel normally, but on this tank full it was lethargic, poor economy, and just plain ill. I filled up at a BP station after half a tank and it was much better, next tankfull and everything back to normal.