Spark plugs FZR 400rr 3tj1

[Evilchicken0]

If he doesn't know where the coils are then its unlikely they've been checked. I thought tight valves would be poor starting and running until the bike warms up and the head expands, this makes a bit of tolerance and valve seals. When the tolerances close even more the bike won't start.

Checking the fuel is getting to the carbs is an easy thing so I started him on that first.

[chris6409]

Will a leak on the down pipe cause it to run crap when hot

[hunter]

NO.

[chris6409]

This is really annoying me now the carbs and jets are clear and balanced valves are ok there is a small leak off one of the down pipes the KnN air filter got soaked in engine oil when some PO a**e overfilled the engine causing it to go into the airbox was ran on crappy old fuel before the carbs got cleaned i dont think its missfireing al though sometimes it pops but theres no loss of power only a spluttering when it warms up

If anyone has any idea

[Evilchicken0]

the KnN air filter got soaked in engine oil

Hmmm have you cleaned it since ?
If not take it out and see if the bike still runs crap. The oil sitting in the air filter can change the mixture (making it over rich), if it runs better then you need to clean the filter, you need to use proper K+N cleaning fluid you'll be surprised how much dirt comes out, then re-oil it with the K+N filter oil.

[levo]

If it is the coils give me a shout I have about 3 sets.............

[chris6409]

How can i check the coils and How much do you want for them levo and thanks evil i was gunna by a standard one because i thought if i dont rejet it after the k an n it will run like s**t is that not the case

[levo]

I dont know how to check I have never had a coils break down.

You have Pm.

[chris6409]

Pm ? Email

[Evilchicken0]

How can i check the coils and How much do you want for them levo and thanks evil i was gunna by a standard one because i thought if i dont rejet it after the k an n it will run like s**t is that not the case

The K+N doesn't add much to the airflow, the airbox is the limiting factor so it won't really need a rejet. It has to be clean though.
As I said before check the fuel and the fuel hoses