Pilot jets

Good evening all you kz people.
I have a question about jetting. I have a set of bs34 carbs that came of a kz1000p, that are being used on a kz1000g. I'm pretty sure that the pilots need enlarging. The bike runs well when opened up, which tells me that the mains are ok. However, the bike does tick over well once warmed up, but i do get some popping on overun, not a lot but a little. I have the fuel screws adjusted to 3.5 turns, which is getting close to them not actually making any diference. Checked the plugs, and they are showing lean. The pilots i have at the moment are 37.5, i'm asking what would it be best to go up 1 or 2 sizes bigger. 

Being the G head had those intake tract injector ports. Are you absolutely sure they are air tight? 

Asphalt900,

Yeah i'm pretty sure there are no air leaks, i tested with the usual tricks and it seems ok. The bike runs and ticks over well with no hanging issues or baulking, and rides good. I have done about 120 miles on it since i got it on the road, but im not sure how far you would need to take it before the plugs showed signs on how it was running. 

Something to verify. When You are considering changing out those Pilot jets, check them puppies when you pull them out. I've Never had to change the 37.5's even when running a sidewinder pipe and pods on a 1075 set-up. All pilot jets are NOT built the same. They had BLEED and NON-BLEED types as shown. Make sure you have the correct ones in there and not some Chinese knock-offs. And..NO, those fuel adjust screws shouldn't be 3.5 turns out, something is a-miss. The reason i mentioned the possible loss of vacuum initially.    

Do you have a friendly MOT tester where you are ? if so you could ask him to stick his emission tester in your exhaust. A high HC reading would indicate an air leak

The pilots i have got are the ones without the holes, i did a rebuild on them when i got them by basically cleaning everything out. I'm surprised that i needed to turn out the screws so far. I'll do another check on all the places it could leak, but i'm pretty sure its sound. Its dificult to work on the bike at the moment as the weather in the uk is pretty crap and i dont have a garage, just a small shed. Just another question, would it be worth putting a bit of gasket sealent on the intake manifolds.

Wookie58,
I'll look into that, theres not alot of bike shops around where i live, but i might need to leave that until the weather improves.

You do not indicate what if any type of air filtration you are using, which depending upon what you are running can and will create a lean mix,

It appears these pilot jets are drilled different. Looking through them it seems there multiple holes in a star pattern so drilling wouldn't be an option so I ordered these.
. 
That being said I replaced all of them after I got the mangled one out. 
rumble.com/v4xgmb5-extracting-pilot-jet.html
This was a pucker time. 
Steve
 

Gd4now,
i'm running the original filter in its original housing. But because i have removed everthing associated with the FI system i had to create a air intake manifold and connect it to the filter box. The only thing that could be a problem, is where the manifold connects to the carbs is not making a good seal. May need some very thin rubber as they are actually quite a tight fit. The picture isnt great but may show you what i have done.      
 

I wouldn't expect a small amount of leakage on the filter side to effect it greatly, nice job on the manifold. Are all the vac take offs on the carbs capped (except the one for the petcock)

Wookie58,

Thanks, i cant take full credit on the manifold design, saw one of alan milyard videos where he did it on one of his kz's, so if it works for him, it should work for me. Yep all the vacuum caps are plugged of, dont need a vacuum pipe for the tap as its gravity fed. Just wondering if the filter has had it, as it is old and may have lost its integrity. Maybe clutching at straws with that theory. If its a dry weekend i'll have a good look at everthing and make sure everything is tight.