I fixed my idle and off idle jetting by putting in a 42 idle jet. I had hard starting, long warm up and off idle perfromance problems. Now they are fixed. If you need help with this procedure let me know.
do you have 98 or 99? your post says 98 but your id says 99. I have a 99 and hate the low rpm carb sputtering. I actually dug up some of my old mags and in the Feb 2000 issue they do say that replacing the slow jet with next biggest size (stock is 38) is what to do. do they make a 40? what made you try 42? in article, they just shimmed needle 0.5mm with washer and that actually cured problem also. I have heard the ivan kits replaces the slow air jet (not the slow jet as you have done) anyone confirm this on a 98 or 99? on his web site when you try to view install instructions for 98-99 it actually shows instructions from 2000-2001, but I think you do same on 98-99. It is more complicated and has to be drilled out and is press fit in new one. where did you get the jets? from the kawasaki dealer? maybe will try this.
How many turns out are you on your fuel screws with the 42's?
A local race shop performed the same treatment on my 02 back in 2004.
Previous owner asked them for a FP kit but they talked him out of it and installed the large PJ's instead. I've heard that 98-99 and 02-03 carbs are very similar.
I'm in the process of jetting my bike right now with a FP kit and have some 38's on the way. I want to see how it will idle and cruise with smaller PJ's. I will agree that the bike has no flatspots with 42's and if on a budget its a cheap bandaid fix.
Does your bike idle right when cold? Mine has about a 400 idle rpm swing from cold to fully warmed. Cold start at 70-90f causes me to apply throttle to keep it from dying and it will want to idle @ 600rpm. I usually have to adjust the idle control, then when warmed up I have to bring the idle back down to 900-1000rpm. In the evening when leaving work it is not as bad.
That and the gas fumes are starting to get old unless you like to get your buzz on before riding[8D].
my full akra equiped 98 only seems to have trouble with running rich rather than lean. stock air filter (demeshed) and +4 advancer.
FP kit, running the stock 38 PJ's, 158 mains, needles on leanest (says not to but its working the best, and i have tried every possible combination) floats on 15mm and pilot screws on 2.25 turns.
about to go take them back to 2.0 turns because the bike is fouling the plugs on the freeway... after a while of riding along with a steady throttle sitting on about 4500-5000rpm at freeway speed, if i go to crack the throttle open to overtake the bike splutters like its misfiring, then clears it throat and shoots off... then it wont splutter on throttle opening until ive been cruising along at 4500-5000rpm with steady throttle for a minute or two [B)]
ive been playing with my carbs since mid december 05... im sick of this
I have a 98 motor but the title says a 99 because I had to get a new frame. (Stolen recovery) It has the stock pipe also. I went with 42s because Houston is at sea level. It took so long to warm up on the choke that I thought 40s would not not enough in the winter. I'm 3 turns out and I do have a Dyno-jet kit but it never cured the low end. It did have air correction jets in the kit but it did not help the low end.
I think 40s would work too if you could tune the fuel screw. I just wanted a little more just in case and it runs beautifully.
Rule of thumb on the fuel screws is, more than 2 turns out, its running too lean. Less than 1 turn out, its running too fat. Thack just caught the other tell tail sign of being a little on the rich side, when it fires and idles with no choke on a cold motor. Sounds like you guys are going in the right direction tho. Good luck
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