Help my 84 GPz750

My name is Nick and I’m a new member. I’m a “senior citizen” and have a nice GPz750 of ‘84 vintage. I recently had it recommissioned after  the covid years. My problem is it will not start. I have tracked it down to the carbs and specifically the pilot jet circuit. No fuel is reaching the engine but petrol comes from the float chambers if I undo the drain screws. 
Apart from the odd pop there is nothing. A strange thing happened when I wound out the pilot screws from the usual setting and pressed the starter. It fired immediately and revved fine and even idled. When I reset the screws to the recommended 2 turns out it refused to start and nothing I do seems to work. I’m at my wits end and would greatly welcome any advice. I feel the fault lies in the pilot needles but I’m open to suggestions. Help. 

Hi Nick, welcome from Leicestershire - I'm sure the carb guys will be along shortly but I suspect a "carb strip and thorough clean" are in your near future 

Those retched painted carbs, never understood the reasoning behind painting carbs!

asphalt900 wrote:

Those retched painted carbs, never understood the reasoning behind painting carbs!

Dunk those Mikuni's into carb dip, to clean the internal passages, and much of the paint strips off...but, not all.  They will look like crap.  Only options are sub-optimal cleaning methods, like ultrasonic, or stripping the paint straight away using paint stripper, then follow with the carb dip.  Been there before.

Regarding paying someone to clean your carbs, unless that person knows what they are doing, like Clay here, all bets are OFF!

BTW, Keihin CV34's with the black paint are 10x more difficult to strip than the Mikuni's.  Even paint stripper struggles with that Keihin paint.  That stuff is tough.

Nick,

Welcome in!

It sounds like a case where the pilot jet circuit is partially clogged.  When you adjusted the pilot screw out you may be letting enough fuel through for the bike to start.  I would NOT do a full strip and dunk of the carbs at this point.  A simple removal and some aerosol carb cleaner with pressurize air through the pilot jet, fuel screw and associated orifices may be OK.

Are you still using the factory airbox or do you have pod filters?  (Dealing with a factory airbox is always a struggle with R&I carbs.)

Just my 2¢, I could be wrong.

Later, Doug

Thanks Doug. The carbs have been stripped and cleaned but I feel sure you are spot on. I’ll do as you recommend and take them off, use carb cleaner and blow through all the pilot circuits. As I said, it started when I wound out the screws but will not start now even if I repeat the procedure. 
I am running the factory airbox and you’re right-the rubbers can be devils to fit. I’ll let you know and thanks again

Ed..You're too kind but i'm dumb as a satchel of acorns. But.. knowing Your experiences, and running fine with screws set out. A couple options. Let it run.....might self clean. Or the "bypass" ports are clogged. That fuel adj is just a backer/fine tuning for the complete pilot system. Sticky fuel residue has lodged in the passage plugging the 2-3-4-5 holes Intake side of the butterfly flap. If it's running fine just adjusting the screw then the jet isn't clogged. Give it a go "senior pensioner", i think we all here are senior eventhough we vehemently deny it ha.   

Ed, I think you’re spot on with the clogged ports and the intake holes and I will be attending to that tomorrow. I must stress that it only started the once and that was when I wound open the screws. It never started again  whatever I did. It was a one-off. I reckon you’re right about the blockages, the screws are fine tuning for the pilot. I’m really grateful to you and all the guys for helping out. I’d really like to ride the Kawa again while I still can! I’ll keep you posted. All the very best. Nick

Welcome Nick.

Sounds like you've had some good advice already.

Now we just need to see some pictures of your ride!

Thanks for all your help folks. You’ve been great. I’m sure I can sort this now. Here’s a couple of shots of my ride and I wish you all happy biking from the UK