Need some expert tuning advice...

Hey everybody,

Finally got my KZP running today...*yaaay*! It is a 1996 KZ1000P with 42K miles on it.
Compression tested good, adjusted the valves, oil and filter change, air filter new. the bike is bone stock. Most recently I took the carbs off and stripped them, unganged them, gave them a pretty comprehensive cleaning, put rebuild kits on all of them; new float needles and seats, new main and pilot jets, new jet needles. On the jet needles I left the circlip in the same spot as the old ones, three slots up from the bottom. Original main/pilot jets were 127.5 and 37.5 and that is what I put back in. The only thing I did not monkey with was drilling out the air/fuel screws, left them alone.

Bike started up and idled nice this morning and while it was warming up I could blip the throttle, no problems. After about 5 minutes I pushed the enrichener back in and took it for a ride around the block. I then noticed I had a definite hesitation/bog early, first 1/4 of the throttle or so. Not a real experienced carb tuner, so where do I go from here? It runs good otherwise, idles good, but the hesitation thing needs to go away. Other than that, the bike runs like a *raped ape*!

One possibility is the fact that you replaced the jets and needles. Unless the originals were damaged this generally isn't a good idea because a lot of the "kits" have parts that are not very precise. You may want to re-install the originals to see if that fixes the problem.

One other possibility is that you mixed parts between carbs. This isn't a good thing to do because the parts tend to wear together and don't like to be moved from one carb to another. Ed

+1, what 650ed said, ...is there a reason you wanted to rebuild the carbs? was it running rough before? do you have in-line fuel filters? how does the inside of the gas tank look? was the gas fresh or old?

Skiprrdog wrote: I then noticed I had a definite hesitation/bog early, first 1/4 of the throttle or so.

On most carbs, the pilot jets control what happens during the first 1/4 throttle. It can also be caused by fuel levels being wrong which (as somebody said) could be caused if floats and needles between carbs were mixed up or new needles/jets from the kit were used. You can check the fuel levels using clear tube.

The height of the needles in the vacuum slides can cause a hesitation if needles were changed or altered.

The bike was running pretty bad, and would only idle with the enrichener pulled all the way out. The carbs ended up being pretty filthy inside, so I stripped them, soaked them, and put the kits on. I was not going to do that (with the rebuild kits) but I noticed that the jet needles seemed to have some wear on them, so that is what started that. I also spent three days checking fuel level with the clear plastic hose, got that dialed in pretty close.

The float needles I had to replace, because they had visible wear on the tips, and I did the seats also. Yeah, I spent several days with the clear plastic tube and think I got the fuel levels dialed in pretty good.
Lord, if I have to take those carbs off again I am going to *scream* :woohoo:

Oh, and I was pretty careful to keep old parts marked/numbered in separate bags after I took them off. If I can get the vacuum slides out of the carbs without having to remove the whole bank, maybe Ill start there, and put the original jet needles back in and see what happens.

Did you say you didn't remove the mixture caps? It might be a minor adjustment.
Steve

No, I did not remove the mixture caps. Do you think I should do that?

Skiprrdog wrote: No, I did not remove the mixture caps. Do you think I should do that?

Yes, if all of us remove the anti-tamper plugs, there's way too many for the black helicopter guys to keep up with.

Good Fortune!

LOL... no black helicopters, but I have been seeing a bunch of Apaches lately, and maybe even a drone this morning... heck, who wants to live forever anyhow

Actually, I have never been closer to dragging this KZP out to the curb, setting it on fire, and putting a sign on it, "free scorched metal to good home" :huh: It has been literally one thing after another.

After carb rebuild, it ran poorly, took the advice of a member here and replaced new jet needles with old jet needles. Ran *awesome* for a day. So I took it for a ride around the block and it died about two blocks from my house (almost seemed like it ran out of fuel) so after pushing it home, put gas in and it started right up, idled ok, but when I let the clutch out and started to roll, would get several feet and it would bog like it wanted to die; if I pulled the clutch in, back to nice idle, if I did not, it died! Then later in the day (it was just before dark, a little cooler, Im in Tucson) it ran fine again, no engine stumbles/dying. Another thing it started doing yesterday was weeping a little bit of fuel from under the gas cap, despite the fact there was *maybe* only a half gallon in the tank!

Anyhow, with these recent *fails*, it somehow does not feel carb related to me (although it still could be) So at any rate, I ordered a rebuild kit for the OEM vacuum petcock on it, so I can rule that out, if nothing else.

I swear, this bike is possessed by some evil, malign Japanese spirit, determined to kill me financially :laugh:

Am thinking -- but not positive --that the following diagram is of the carb at hand.



Note the small passageway where fuel from the main jet gets to the pilot jet.

The small passageway must be clean and clear and unobstructed.

It's not enough to clean only the pilot jet and other passageways.

One method to try cleaning the small passageway is to spray carb cleaner into the main jet while blocking any escape route except through the pilot jet, and watching the spray exit via #2 and #3 orifices into the carb bore.

Once the pilot circuit has been re-cleaned, would assure that no gasoline whatever enters the carb without passing through an after-market in-line fuel filter.

The petcock screens alone are woefully insufficient as fuel filters.

The pilot circuit is largely responsible for good low rpm (idle) performance and a strong steady pull-away.

Good Fortune!

Good advice from Patton as always.
I would also add it takes two to three cleanings before you get them really clean. Just soaking them won't do it. Every passage, and I mean every one, has to be checked and cleaned with carb cleaner and compressed air.
Love the old police bikes BTW. I have one on my MC bucket list.
Good luck.