Spark plugs - what does this mean?

[kevin567]

I just picked up my 07 Hayabusa last weekend and have started to customize it for my use.

I just replaced the sparkies and pulled these ones out. They are in order of the cylinders in the bike from the rider point of view.

The leftmost cylinder's plug had white residue and a bit of corrosion on the body above the threads I guess water must have gotten into the chamber above the engine at some point?

The second from the left was the darkest of the 4 and looked wet when taken out of the engine. The others were all a normal light brownish colour.

What does that second plug mean for my engine?

Thanks...

 

[anark]

It means that YOU NEED TO TAKE BETTER PICTURES! lol. Hard to see anything from your picture.

Dark and wet means running rich. Fuel rail may be stuck open, bad plug, bad plug cap, others can chime in.

Allan

 

[kevin567]

Sorry... in my garage with greasy hands and the skies opened up. The only plug I was a bit concerned about was the second one. The other three looked normal.

I can see the fuel rail -- are there valves inside the rail? How would I go about checking the one cylinder?

BTW I love how easy it is to access everything under the tank. I have ridden cruisers (don't judge) and still have an FZ6 (again, dont' judge), and both of those were a royal PIA to work on.

Kevin

 

[sircastic]

Sorry... in my garage with greasy hands and the skies opened up. The only plug I was a bit concerned about was the second one. The other three looked normal.

I can see the fuel rail -- are there valves inside the rail? How would I go about checking the one cylinder?

BTW I love how easy it is to access everything under the tank. I have ridden cruisers (don't judge) and still have an FZ6 (again, dont' judge), and both of those were a royal PIA to work on.

Kevin

Your picture isn't large enough / clear enough to see the plug properly. Black and wet means excess fuel in the cylinder. It would be caused by a number of things but most likely a misfiring spark plug if the others looked fine.