'02 Kawasaki Ninja ZZR1200, (4 carbs)

Didn't ride much last year, and it sat pretty much all winter moslty unridden... started a few times, always on a tender and in a heated garage. I used stabil in the tank.

Anywho... it was really hard to start, had to use full choke and hold the starter for a solid 2 seconds it seemed, reved right up and walked the choke back down and let it warm up. Was sputtering abit, but I let it warm up then shut it down. Started right up on second try with no choke when it was warm. Didn't think much of it... drained the old oil, cleaned up the chain, got the dust off etc, normal routine.

I took it for a spin and it stuttered like mad below about 3.5k rpm then wakes up and is smoth as a babies *** all the way to red. Once its back down below 3.5 it stutters around and theres a massive delay in throttle response. you can crack the throttle and shell just sit there and craaawl for a few seconds then bam, shes goin.

back in the garage i pulled the tank and filter, checked for anything obvious (vac tubes pulled, crackes, leaks etc). nothing out of the ordinary. pulled the spark plug wires off and 2 of the spark plug wells had about a half inch of coolant around the base of the plug (plug wells sit verticle in this motor). mind you this is actually considered "normal" for these bikes, they are like sr-71s apparently haha. pulled the boots, dried em, changed the plugs to a new set (old ones where new last year and where still clean) but why not. gave the carbs a splash of carb cleaner each, looked for debris etc... put her back together. didnt get a chance to try it out, sat overnight.

this morning, starts right up, very happy. i get about a half mile or so to work and i'm very happy, feels like shes perfect. theeeeen it starts to get a delay in throttle response down low. a few blocks later, and the studder comes back enough that the idle surges regularly... but agian, once above 3.5k shes all ballz to the walls humming like a tuned.. humming thing.

pulled the tank again, double checked the filters and hoses, checked the intake ram tubes for spiders or whatever... put the "old" plugs back in... and the same thing happens.

i'm at a loss, whats goin on? only thing i can think of is maybe the carbs need to be synced? but the symptoms are really strange to me. i even put some seafoam through her and fresh gas thinkin maybe it was water logged from condensation or somethin to that effect.

any ideas would be great, its a pain to get to the dealership, get a ride home, then ride back, and god knows what they will pretend to find and charge haha. lack of reliable shops around here!

 

Anyone?

 

well hey....we have a small engine repair shop here an work on all forms of cycles and atv's etc. I can say with the utmost certainty that even though you "stabiled" the gas...that wasnt enough. The problem is in the carbs, primarily the low speed or "pilot" jets.....there is something at least partially blocking them.....fuel sediment or whatever and the only way to make the bike dependable is to remove the carbs and clean them / blow them out.....take all the jets out and verify that they are clean....put it all back together and THEN sync the carbs....use super-unleaded fuel....ethanol free if you can find it.
pm me if you need more help....glad to help a fellow rover owner.....
Rod

 

your low speed idle jets a gummed up

 

Disassembling a carb is beyond my desire to attempt lol. i bought two bottles of stp carb cleaner for the gas... ill take it out on the highway and cruise at a low rpm see if the symptoms improve before i bite the bullet.