kz1100 jetting trouble

Hey everyone, after I added a 4-into-1 Kerker pipe and a K&N air filter to my stock airbox on my 83 KZ1100 L1 LTD I'm having a hard time getting my jetting right. I went from a 117.5 main jet to a 122.5 and left the stock pilots alone which my service manual claims are 37.5, I don't remember for sure what they were when I took the carbs apart. The bike hesitates some at low rpms and occasionally pings a little bit but pulls much better at high rpms. I'm running premium fuel and installed a new set of plugs which seemed to make no difference. I was hoping someone could point me in the right direction of what a proper jetting setup would be without having to buy a bunch of jets and use the trial and error strategy. Thaks Mike

Also the bike was all stock and ran perfect before I changed anything and has less than 9,000 miles on it.

eaton wrote:

The bike hesitates some at low rpms and

first guess would be:

1) Richer pilot jets

2) richen the needle position

Would have to shim the needles, I believe they were non adjustable on the Cv carbs. CV's dont like pod air filters with me

mtkawboy wrote:

Would have to shim the needles, I believe they were non adjustable on the Cv carbs. CV's dont like pod air filters with me

Not trying to sound gloomy, but one of the pros on the other Kawi site said something to the effect that the 1000's and 1100's can't be made to run properly with pods.

The cost of a stock airbox might be a good investment to avoid a lot of misery.

I didnt say they couldnt be made to run right, I said I couldnt get them to run right. Way easier for me to leave the air box on:silly:

My misunderstand.

BTW: was the carb setup running strong with the stock header before you put on the Kerker?

based on symptoms:

The bike hesitates some at low rpms and occasionally pings a little bit but pulls much better at high rpms.

Sounds like the main jets are right. Low throttle opening hesitation is usually pilot jet or needle position.

Pinging means timing is off or you need better gas.

I would try running plain old 87 octane, no need for premium unless the motors been built up and such. These things were designed to run on 87. And i would recomend the stock airbox be put on a.s.a.p. I went through the pods on my 74 z1 900, and after a bunch of fiddling around i just put the stock airbox back on.

He has the stock airbox with a K+N filter in it, my mistake when I read it I thought it said K+N air filter like a pod.

I read it wrong too. I put a K&N filter in the stock airbox on my CV carbed GPZ750 and didnt change anything, but Im at 3700 ft. I would agree with 1 up on the pilot and a .030 -.050 shim under the needle at most or if you can find one, a Canadian adjustable needle with the clip lowered one {raised needle}. Its a lot of work, personally Id put the stock filter back in, you will most likely need a $75 set of airbox boots if you take the carbs off. Have you checked for vacuum leaks?

For starters thanks for all of your advice. To clear a few things up the bike ran strong before I did any modifications to it, and I am running a stock airbox setup with a K&N air filter. The carb boots and air box boots look to be in excellent condition and I can't locate any vacuum leaks. I live in southeast Kansas so the elevation is around 750ft if that helps in diagnosing. Thanks for all your help, Mike.