TOPIC:

Hey all I will give you a little background on the bike it's a 1979 kz1000 ltd it wasn't running when I picked it up. I did a compression test 135 to 140 on all cylinders the carbs were completely pluged so I cleaned them and put kits in them. When I took them apart I noticed the bodies were stripped where the float bowl screws went not all but some it had 15 pilot jets on the out side cylinders and 17's on the inside it had 102.5 main jets the bike had stock exhaust and a bread box air filter. I put a kerker header on it with a baffle (very quiet) and I put the 105 main jets in the kit.I got the bike started it didn't want to idle very well the outside cylinder on the brake side was allot cooler than the rest but it ran decent in the upper rpm range it was leaking fuel from the float bowls so I didn't ride it much. I got a set of carbs off ebay same size (26 mikunis no accelerator pumps) I had some 115 main jets and some 17 pilot jets I put them in got the carbs back on the bike with pod air filters and I cut the baffle down in the kerker took the small inner pipe that is about a 1/2 inch in diameter out and left the packing out (sounds much better ) the only other thing I did was the wired george coil wire upgrade.I started the bike it started much better let it warm up adjusted the idle mixture screws and took it for a test drive it pulls great till it hits a little over 1/4 throttle then it sounds like it's blubbering and won't clear up I ran it again and it started the blubbering again I pulled the choke up slowly it didn't have any affect till it was fully closed then ran worse. From what I have read on here with the pods and the header it should be a little lean.It sounds like it has an electrical miss witch it didn't have before or it's somewhere in the carbs.It also has a pointless ignition all your help will be greatly appreciated Bart

www.iwt.com.au/mikunicarb.htm

thanks I guess I can put the 105 jets in and see if it gets better or worse

Make sure that you are using actual Mikuni jets. Most kits have knock off jets and the numbers stamped on them are not the same sizes as Mikuni. Personally, my K.Z.s are set up on 117.5 mains and 20 idle jets with pods and a free flowing pipe. This works for me. The bikes run a little rich and are happy.( I can't get a real clean transition with this new crappy gasoline without the #20s.) One thing that also comes to mind....make sure that your advance is working. You might want to remove it and lube the mechanism and see if the springs are damaged...

burbbleing is typically rich.

running good on bottom makes it sounds like the pilots are okay.
but burbbleing sounds like the mains are to big.
as zero said check the advance mechanism as well.

leon

Thanks I'm going to check the spark also the blubbering I'm referring to may be 2 cylinders dropping

If not already done, would perform the clear tube test on each carb to assure that all fuel levels are within specs.

A too high fuel level inside the float bowl results in excessive richness, even with an otherwise perfect carb.

Good Fortune!

thanks Patton I will try it the timing was fine it dosen't start missing till 6000 rpm's running down the rode the choke only makes it worse but I haven't checked the valve clearance yet that may be it I will check it next but will make something to check the float level

Good Fortune!

lhttp://www.z1enterprises.com/ShopByCategory.aspx?name=Oil+Filters&description=Volume+Discounts+on+Oil+Filters&category=010302

I checked my valve clearance they were all in spec I did check the float level on the two outside carbs I(I had a hard time stuffing a hose in the drain screw hole ) one was pretty high so I set it down and ordered the tool so I can check them took it around the block sounded better so I feel I'm on the right track.I love this old bike and I really appreciate all your help I think back on when I bought the bike it didn't run at all now we are fine tuning it what a diamond in the rough.Thanks again for all your help

Sorry, I have to ask... I've seen this process for checking the fuel level, and I know it is related to the adjustment of the floats... but if the level is wrong, do you have to empty the bowl and remove it each time, or is there an external adjustment screw for the floats that I didn't see?

Yes, you will need to empty the bowl, remove it and the float, bend the float tang a little, and repeat until the correct level is achieved. It's possible to do this without removing the carbs from the bike, but if the carbs are already off the bike it is easier as you can make a carb stand using old carb holders attached to a board which makes access to the floats easier. Ed