Kz1000J Carbs

Looking for carb advice for my 81 KZ1000J...engine built with a 1075 kit, Web Cams, headwork,trans work, crank welded, pods and a Kerker header...currently running new Mikuni 36mm flatslides which work great from 3grand up but not so streetable below that rpm,

Try going to Mikuni international for the specs on jetting for your model. My 33's were set up for Honda/Suzuki when I got them. The jetting for the Kawasaki was much different.

I am running a GPZ1100 engine with ported head, 1175cc piston kit with 10.50-1 compression pistons, Web camshafts at .385 lift, Same Kerker as yours with competition baffle, Mikuni RS36 carbs. Mine runs great from idle to WOT, there is a very slight lean spot between 3000 rpms and 4000 rpms but other than that it idles smooth and throttle response is great.
The Mikuni's were pretty much jetted spot on out of the box.
RS36's is probably a little to big for your engine, they are almost to big for mine but I am planning on doing more work to it so I went with the bigger ones. If I were to keep mine at where it is I would have got the RS34's. The smaller carbs are easier to dial in in the lower rpm range.
Another thing that will effect low end performance will be porting, how big did you go with the porting?

Not sure about porting, Larry Cavanaugh did all the engine work, bike pulls great from idle to redline,hard to keep the wheel on the ground...just takes too long to warm up pops and backfires without the choke, takes about ten minutes to idle right, carbs were out of sync so I fixed that and it made a big difference ,played with jetting a bit but still runs fat through the entire rpm range, Larry suggested CRS 29 Smoothbores so I'll look into that...have to find a buyer for my 36mm Flatslides.

Were these used carbs and have you verified the needle jet, main jet and idle jet are factory sizes? If bought used then someone might have played around with the jetting and screwed it up.
Maybe someone will trade you a set of RS34's or CR29's for yours.

Bought them brand new...paid a lot for them!

I was on the jetsrus web site looking at new float and needle valve for my 33's. No longer made. There's a chart that tells you what the jet sizes, throttle cutaway, main nossle, needle, and air jet are for the different bikes. I bought mine used and have been Fing with them ever since. With their help, I'm there, almost. Check it out.
Steve

Thanks Steve I'll look into that...