ZZR600 Running problems

[Tartan Terror]

Hi folks,

my mate's ZZR600 is running like sh*te! It won't pull in 5th & 6th although he does say that it will rev cleanly when the clutch is pulled.

1st to 4th it pulls fine and will rev clean.

He had just fitted a full Micron exhaust system prior to the running problems but this could be purely coincidental.

Any ideas before I get my hands dirty?

 

[doyle]

Might be an idea to stick the old exhaust back on

Seems a bit of a coincidence .

 

[Tartan Terror]

As with most older Kawasakis the old exhaust has disolved!!

I was thinking a problem with a coil breaking down under high load. Going to check carbs out and balance if required, look at plugs etc and check fuel flow too whilst I am at it.

 

[karlp]

You can simulate a high load in 2nd 3rd or 4th by trying to accelerate from low rpm up a steep hill.

Usually after fitting these aftermarket exhausts a replacement of jets is required to get it running correctly.

Coil breaking down - I think you are looking in the wrong direction

 

[Tartan Terror]

So a jet kit may well be on the cards then?

Dynojet or anyone else supply these to suit?

 

[Kenny]

Race exhausts work better at the top end..so I doubt that is to blame.

Really hard problem to pinpoint.

Does it misfire in 5th or 6th......does it feels like fuel starvation ?

 

[Tartan Terror]

No missfire as far as I know. I am only going on his version of problems so until I get the bike I won't know for sure and try it out myself.

seat of the pants dyno may reveal more.

 

[KMD]

Just a thought, but if it's revving in the lower gears, it's possible by the time it gets into top the float bowls are low and there's insufficient fuel flow.

I'd start with the breather on the top of the fuel tank, then move to fuel levels in the carbs, set the pilot screws and then balance the carbs.

Has the bike been stood? Any chance it could be varnish contamination on the jets/floats?

Also, the strainer in the tank could be clagged up. Is there a fuel tap below the tank on these? Is it a vacuum operated one? Possibly a diaphragm split?