Pointy Misfire

[BomBalong]

Hi again org.

After riding back from work ive been noticing that if i open the throttle too hard it either goes like what the SV does when the front cylinder has no spark, or it bogs momentarily then gives out a rather large backfire, or fart as my little sister says :D

does anybody have any idea what it could be, the spark plugs got changed about 2000 miles ago. but afaik the HT leads have not been changed.

Thanks alot, all help appreciated.
Ben.

[BomBalong]

no ideas anybody?

[Speedy]

Water in the front plug lead?

[The Guru]

Fuelling issue? :-k

[independentphoto]

does it idle smoothly at the correct engine speed?

[BomBalong]

speedy: its not the water in the plug, its been doing it in the stonking heat.

The guru: I think it may well be a fuelling issue, she can get abit lumpy if im near to empty.

independantphoto: that can be in what mood its in, sometimes i can start it and it wont fast idle, but thats occasional, 95% of the time its okay, but it can cough if i open the throttle from idle at times. btw my idle is around 1450.

[Speedy]

speedy: its not the water in the plug, its been doing it in the stonking heat.

So you've had this problem for a while then.....(No stonking heat recently!)

If it coughs and mis-fires under load, I'd start looking for an ignition fault. H/T leads may look OK, but not necessarily are. Will it mess about if you rev it in neutral?
If it does, wait until it's dark, get someone to rev it whilst you look around the plug caps and leads, you may see some sparks!

What colour is the exhaust outlet? If it's more of a White colour, it's running weak, which could indicate an intake leak, (pipe off/split).
If it's black, rich. Which could, if VERY rich, make it run funny.

I'd have a serious check around the wiring and switches though.

[BomBalong]

yeah my exhaust outlet is black like quite black, every now and then it will have a moment in neutral not revving up right, so i think what youre saying could be a good indicator as to what my problem is.

[Speedy]

However.....

If its mis-firing due to ignition problems, the exhaust could be "sooty" due to partial combustion of the fuel.....

Is the engine mechanically noisy? Has it been rattling?

Does it do this all the time, or just when under load?