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Thanks, they seem to be within spec but like you say its best to measure them than eyeball, I'll give this a go to be on the safe side.
I was thinking an air leak could still be a possibility im going to chexk the inlet rubbers again with some fuel starter fluid or propane, i used wd40 last time but not sure if its the vest thing to use. Going to sync the carbs too, is there a base line for those sync screws in the middle to be set at before I begin? I guess its something I've overlooked so far, I'm not sure if it would help on the no rev situation but any things worth a shot.

To check for air leak let bike warm up, turn the idle down low so easier to spot any change. I have read that carb cleaner or starter fluid or propane are better than WD40. If starter fluid is ether then be very careful. My only air leak was very obvious. Failure to tighten engine side boots led to engine racing.

Edit; how many turns out are mixture screws currently ?

The only way I could ever synch those CV carbs was using a Morgan Carbtune. With non CV type carbs I understand it is possible to bench synch and find a ballpark for the throttle stop screws by placing a wire under the mechanical slide and adjusting screw until wire drops out. I don't know if possible to do similar with CV carbs by placing wire under throttle flap/butterfly. I have thought about it but once I bought the Morgan Carbtune I had no need to try.

Perhaps someone else can jump in here

Ok that makes sense that if it was an air leak it would be continuous and noticeable, I'll still double check it anyway but doesn't seem likely from what you say.

I think I set the idle screws to what they were before, which was 3 turns, this was something I was going to play around with though as I know stock is meant to be 2 but before it wouldn't ru right with that amount out.

I've borrowed a set of carb tunes they are 2 cylinder ones but I've been told you can still balance them just 2 in sequence at a time instead of all four together. A mate of a mate said he thinks my problem is timing related instead of carbs and told me to check the advancer again, it looked spotless last time but guess it can't hurt to take it off and give it a good lubricating up, I should of done that last time I suppose rather than just assuming it was good because it looks in good nick.

Ok that makes sense that if it was an air leak it would be continuous and noticeable, I'll still double check it anyway but doesn't seem likely from what you say.

It's worth checking for air leaks. A large leak will make engine race. Small one may have different effect.

I can't remember if I asked this before but are the tiny washers and o rings on the air mix screws in good shape? I was curious about the current position of the mix screws. It wouldn't hurt to start at stock setting and try turning them out 1/2 or turn at a time and look for improvement.

You can check and lube the advancer in place. If it is stuck and you have to take it off make sure you mark it and put it back the same way. If it goes back upside down the timing could be 180 degrees ass backwards

Ok cool, ill get hold of some starter fluid tomorrow and give it a go.

Yeah i think we discussed it somewhere in the thread about o rings etc and they are in good nick it seems, ill go back to stock setting and try them at 1/2 turns out and see if does anything,
Postie turned up today with my lost diaphragm that turned out to of slipped behind some parcels in their van (yay) so will fit that at same time and hopefully will help too.

Will bear that in mind for the advancer, i dont want to mess things up any more than they might be so good advice thanks

I just did the air leak checks with propane and no leaks it seems.
I got the other set of carbs through too and they arent in too bad condition diaphragms good etc but a bit dirty inside so need a good clean, they have some slightly different size needle's (N10C) and main jet is 100 compared to the N10a's and 90's i have on my set.
I put on the replacement diaphragm on the busted one i have and its made a bit of difference, The bike actually feels like it wants to go now, I'm sure it must be all carb related. Only thing is where to go with it now? Im scratching my head trying to figure out what else it could be on them and the only thing i can think of is they are still blocked up a bit? i did turn out the fuel screws in increments, 2.5 turns was about the same as 3 but they are all out to 4 turns now and a bit better, i was gonna go another turn or so but im thinking if they need to go out that far just to run better then something still isnt right and should concentrate on fixing that first.
I think next step is i will clean this other set out and give them a go on it and if it runs a bit better then i guess i will know for sure whats causing my problems and perhaps these ones will be a bit more forgiving.

I also went in to the advancer casings again and its moving freely so just oiled it up.

Apologies if already covered, but 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.

Good Fortune!

SK - i wouldnt free rev your motor too much mate.Not good.

Ok thanks, will bear that in mind.
I put the new carbs on today and the bike is running better but still seems to have the same problem so feel like I'm going round in circles a bit. I think it can't be a carb issue now as its pretty unlikely that 2 sets of fairly decent carbs would have exactly the same symptoms? I've got a strobe gun coming from a mate so I can check the timing, I was wondering though if the timing is out is there actually anyway of adjusting it, as I don't see any way of correcting the plates. The screws that hold all the plates etc seem to be pretty static positioning wise and there doesn't seem to be reference to timing adjustment in the manual other than doing it when the cams/chain have been removed?
I'm just a bit stumped now, it doesn't seem to be carbs/fuel, air system, ignition system, etc etc, it feels lean but don't see how it can be there are no leaks and carbs are idling good and seem to be working as they should?
Diapghrams are all good now too, have tested them using the finger over air hole method and they drop slowly when covered so don't think there is any issue with them anymore.

On the plus side I did slim the seat down today and looks a lot better than that big old king and queen seat

Edit: I just had a thought, could it be that the air filter is to blame?! I just did an eBay search for a filter and the one I have in my bike looks like it could be an aftermarket high flow one, could be on to something here!

Seat didnt turn out too bad, think I need some stiffer foam though, can feel the metal on the bumps a bit too much now!

SK see how it is when you get that timing light on -
Is your air filter foam or something else ?
Are you still hitting that wall mate ?
First decent pics i have seen - very tidy machine.
Can you get hold of some of the Black high compression foam for the seat - it is bloody fantastic - (you dont sink to the bottom like normal foam) - absorbs bumps very nicely and returns to shape. I have about an inch thick layer over the original foam - great stuff.

Cheers man, yea its a minter I'm almost scared to ride it in the crappy winter salt laden British roads we have here, Ive been trying to avoid the rain! Luckily I have access to a car now so I can skip the bad weather rides, luxury lol.
That high density foam sounds the trick, I think I've seen it on eBay I'll order some on payday got a stock pattern air filter on its way now too. The one I have is black foam, when I googled filters it looks a lot like the US branded 'Uni' ones which are k & n like it seems. I had a k&n on my CBR for a bit and it made it run like pants so I doubt its helping if it is.
The bike is hitting the wall still at around 6k but it really feels as if it wants to go if you wring the throttle since I've sorted the diapraghm out. I could probably get a little more if i really thrashed the guts out of it in every gear but i think its wiser not to be too hard on it until the problem is sorted. Its got that annoying slow drop/hanging on the Revs still too.