For what it's worth here is a picture of the adjuster and springs between carbs 1 and 2, looking from the air filter side.
Number 1 on the left. The bit between the adjuster (at top) and the bottom spring is attached to No 1 spindle. Adjuster and bottom spring seat is attached to No 2 spindle. The top spring is just to hold the adjuster at the set position.
I guess if No 1 butterfly was fully closed (or some how stopped from fully closing), then screwing the adjuster down would open No 2 and also 3 and 4 at the same time. If you think that is a possibility you could try screwing the idle adjuster (on flexible cable going to bottom centre of carbs) in to partly open all the carbs and see if No 1 to 2 adjuster still moves No 2. It shouldn't.

Details

All sorted!


Thanks for everyones help, especially the pic you posted Limax2. When I put the "new" carb number 1 onto the others carbs I just jammed them together, with the result that the tab of the adjustment lever from carb 1 was in the middle of the spring that should have been below it, as per your photo, so that the screw at the top contacts with the tab.


It was a bit of a fiddle to get the tab in the right place and the spring jumped out more than once. About 6 times!!! In the end I put the spring in position then put the carb back on and used the two long bolts that connect all the carbs to pull it in slowly. Once it was just pushing against the side of the spring I managed to flick it underneath with a screwdriver.


The reason I didn't spot it was because the breather tube lies right in front of the adjuster, so in the photo Limax2 posted it would obscure the screw totally.


As for the throttle not snapping back. I think I had managed to cross over the two cables underneath the fuel tank. Fixed now.


And the Carbtune works properly now and I've balanced the carbs so she's so much better now. Not spot on, but it's my project bike and everything will be coming apart again soon. Just need to ride her to see how she runs with the pods and the Dynojet kit fitted.


Thanks again folks.

Thanks for the suggestions guys, especially the extensive post by His Dudeness.


I have limited time today, so here's what I've done today.


Firstly swapped over the hoses on the carbtune and I still get the high reading from the left/nearside carb. It's right at the top of the meter. So It's not the meter.


I've pulled the carbs off. I can't really see anything wrong, but bear in mind I'm new to working on carbs, so please treat me as someone with no knowledge.


I had a look at what happens when I turn the balancing screws and found something interesting. I'm guessing that moving the balancing adjuster screw changes the angle of the butterfly in just one of the carbs? Please confirm or deny this.


Looking at the original carbs, plus the replacement from the ones I bought from Deefer666 I can see that when turning the balancing adjuster screw for the two left/nearside carbs, the butterfly in the carb on the inside of the left/nearside carb moves, but the outer one doesn't appear to move. Looks the same on the other two carbs, just one butterfly moves.


However when I do the same thing on the replacement carbs, with my mangled carb on it, I see that the butterfly in the left/nearside carb moves, but not the one on the inside of the left/nearside carb! That confuses me, as it's the opposite of the other set of carbs. Surely the same butterfly would move? If only one butterfly moves when making adjustments between two carbs then perhaps I should swap the carbs back and just install the replacement carbs from Deefer666?


Hope that all makes sense.

I had to replace one of my carbs as it was damaged due to air screw being seized in place. I got a secondhand set (from Deefer666, thank you) and just used the one carb I needed, which was far left side of bike.


I have pod filters fitted and after switching the damaged carb thought I should balance the carbs. So bought a Morgan Carbtune balancer and tried to balance the carbs. Problem I'm getting is the carb I replaced is reading virtually off the scale and miles apart from the carb next to it or any of the others. I've adjusted the balancing screw pretty much through the whole range and I can't get it to come down. Have I missed something out? I've never balanced carbs before.


Also after swapping the carbs and refitting them the throttle cable is quite sticky in operation, that is if I let go of an open throttle it doesn't really snap shut.

Thanks for the kind words and sorry for the lack of progress recently. Project is still on the go, just not had chance to attack it as it's track day season at the moment. Speaking of which, I blew my Daytona 675at Oulton last week and I'm off to Valencia Friday week! Interesting few days ahead. 


I see that wrap around frame idea as more for a sports bike than an upright. Not sure it would look right on my kind of build. Plus I really like down tubes!


If you were to do it I'd want to take it someone who knew what they were doing as it could seriously affect handling, stability, etc.

Ye must be made of money. Spray lube is a rip off. Dirty old engine oil does the job

Yup. I live in Jersey where everyone is a millionaire! 

If I do encounter problems then my first plan is to fit the CDI from a YZF600R Thundercat as this uses virtually the same engine. I've looked at the wiring diagrams for each bike and it all looks virtually the same (minus the speed sensor on the Thundercat), with the same colour wires going to the same places. So I've got a second hand CDI for twenty quid and we'll see if that will work.

Haven't got that far yet, so haven't tried it.

Still a work in progress for me.

Thanks I'll bear that in mind. Just waiting for Deefer666 to see if he has any kicking around, so I'll give him first shot at making a sale.

Need ONE carburettor for the outer left/clutch side of the bank of four for a 1998 FZS 600. Cosmetic condition not too important, but all needles, jets, etc must be moving freely and not seized in place. That I have already! 


Failing that a complete set will have to be bought, so anybody got a complete set they wish to part with?

Damnit, ya beat me! 

You're in denial. You already realised you were beaten with your comment: Damnit, ya beat me!




 

122 Euro. That's about £88.

Dropping the swing arm is really straight forward and pretty quick. You could do it with the rear wheel in place, but much easier with it removed.

If you drop your swing arm out you can fit an endless chain.