Hayabusa 2nd cylinder sooty plug question?


not sure if this is the right place to put the question (sorry if not)

but basically all was going well until a few weeks ago, im getting irratic idle at low down, as soon as you hit the power tho it takes off.

its had alot of engine work done but the main thing to note is its had the head skimmed, and i previously had problems with the fuel pump but have replaced that and cleaned the injectors

the issue is that i figured it was just bad plugs so i bought new ones and unfortionately the problem continues

all other plugs are fine but 2nd is black/sooty and the idle is still a bit unstable, my question is basically has anyone had this problem before? and whether its ignition/injector related?

or does it look like a valve clearance/compression issue?

any advice is greatley appreciated thanks alot guys!


So the old spray it with cleaner wont work then this time? Is there anyway I could test this at home maybe? Like putting air through it or something? I have a compressor if that helps? Thanks for your reply!


swapped the coils around and it didnt seem to make a difference, pulled the injectors and blasted them with compressed air and now they are all the same colour

thanks guys