BS34 KZ1000P

Alright so I'm beating my head on a wall and decided to take a break. I'm working on a 2002 KZ1000P bike with a little over 60k miles.

I just finished installing the carbs I rebuilt with new engine-to-carb boots to eliminate possibilities of a vacuum leak. I rebuilt the carbs with Sudco kits, put in 127 jets instead of 122, same size pilots, and it came with adjustable needles. I put the clip right in the middle of the needle. The emissions have been removed and reed valves plugged.

Right now, the bike has an occasional spit back through the air cleaner box and revs up, and is slow to return to idle. I performed an ohm check on the stock coils, which checked out on the primary and secondary windings. Installed a set of dyna wires since the stockers were hard as a rock.

Any ideas? Should I put the stock needles back in to see if that alleviates the problem?

And before anyone asks, yes I installed the plugs over the pilot jets.

Where are the pilot screws set? Did you measure fuel level in the float bowls. Is the bike modified in any way? Airfilter installed?

A hanging idle suggest a lean condition.

I started the screws off at 2.5 turns out, brought them in to just 1 turn out to try and richen it once I heard the occasional pop. No I have not measured fuel in the float bowls yet. The bike is not modified and is stock, air filter is installed.

1 turn out is way too lean. Try 3 and see if the hanging idle goes away.

Have you vacuum synced the carbs yet?

Nessism wrote: 1 turn out is way too lean. Try 3 and see if the hanging idle goes away.

Have you vacuum synced the carbs yet?

Negative on the vacuum sync. Trying to get her a bit more stable first. Just for clarification, turning the mixture screw in leans while turning out richens? If so, I had it backwards, I was turning in to richen and turning out to lean.

Valves adjusted?
Steve

I haven't made it as far as checking the valve lash. I'm going to try and change back to the stock needles and see how she acts.

Well I'm stopping for tonight. I swapped back to the stock needles which made a noticeable difference on start up and idle. But there is still something off. Next step is checking the valve lash I suppose.

Thanks for the tips so far guys.

If you haven't done so go with 17.5 pilot jets. Carbs spitting back through the intake at idle and hanging idle usually means lean in the idle circuit.

i have an 81 kz1100 i'm trying to resurrect. random coughs out the front of the carbs, huge hanging idle.

tightening the intake boots helped. then i sprayed ether on the intake boots, and idle speed SKYROCKETED. mine has cracked out rotted intake boots.

Yes you changed the boots, but doesn't mean they aren't leaking for some reason. Also, did you plug the three vacuum lines?

I could see valves causing spitting out the intake, but not a hanging idle.

I'd like clarification also. On the 34 carbs I'm looking at, it appears the mixture screw is air, not fuel. So, is IN leaner, or is OUT leaner?

When a pilot screw is located on the "engine side" of a carb, it's usually a "mixture screw" as opposed to an "air screw" which "air screw" is usually located on the "air-box side" aka "air-intake side" of the carb.

A pilot "mixture screw" turns IN to lean (providing less air/fuel mixture) and OUT to enrichen (providing more air/fuel mixture).

A pilot "air screw" turns OUT to lean (providing more air in the air/fuel mixture) and IN to enrichen (providing less air in the air/fuel mixture).

Most CV carbs have a pilot mixture screw



VM manual slide carbs may have either pilot air or pilot mixture screw



And to keep things simple :ohmy: , there's of course at least one known odd-ball carb that has both a pilot air screw and a pilot mixture screw. :lol:


Odd-Ball - Having both types of pilot screws



Good Fortune!