Before I get 'told off' of putting this question in the 'wrong place' can I say that I did ask the question on the NSR Discussion section nearly a week ago without a reply.
The first part is about how I cured (only by a process of elimination..and not a little luck) my bike that was hugely difficult to start and then only ran on one cylinder for about a minute before running on both....here goes.....

As a bit of an update....
I rebuilt the carbs with NEW slow runner jets as the originals seemed to have different sized holes. I didn't block the power jets (might try that later) but fitted 130 mains to keep on the safe side whilst running in!

I also checked my ignition coils, my pickup wiring by the rotor and all other wiring. Refitted everything and then switched ignition on, pulled on choke and gave it one kick and it fired then Very Happy Very Happy Very Happy it started on the 2nd kick Laughing Laughing

I let her warm up a bit and then went out for a ride. Pulled really well but I left a trail of smoke behind me like a screen Embarassed

She ticks over quite well at around 1500rpm but is hugely rich at up to 1/4 throttle openings (roughly)! Would you clever folks suggest the air jet settings. I have then set at 1 1/2 turns out.
If I adjust them without the tank and airbox on, as I can see no way to get at the far carb, will I need to do anything special with the pipe (plastic piece) that pushes into the bottom of the fuel tank (with the filter in it I believe).

Cheers
Mike

p.s. It now always starts on 1st or 2nd kick even from cold. (Smug Smiley face here!!!)
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I don't mind dying...I just don't want to be there when it happens!

It seems from reading your post that you have 3 questions.
1) It smokes a lot. So I guess you want to know what you can do about that.
Well I would initially suggest making sure your oil pump is set correctly (Assuming you are not on premix). Somehow I suspect that you have already done this, but it does no harm to double check I guess.
2) It runs rich at 1/4 throttle, so I guess you want to know what you can do about that.
Well,the air screw is set about right as per NSR-World guide,..here. And you have new slow jets, and I assume standard needles? So not too much seems to be wrong. Maybe,... maybe, if the oil pump is set way rich,... as it appears maybe the case??,.. then setting it correctly might fix your low throttle richness problem? That is a bit of a long shot, sorry.
3)Because you are setting the air screw with the airbox off, you seem to think that you may need to do something with the "pipe (plastic piece) that pushes into the bottom of the fuel tank". I'm sorry but I have never taken the tank off an MC21 so cannot help you here. But in the big scheme of things, I doubt that there is a HUGE difference at low throttle response with airbox on vs off. Please correct me if I am wrong,.. someone.
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[color=#808080][size=9]Yes,.. I too know how to waste Time and Money,...

Many thanks for your reply Tuckerbag.
I had suspected that it was 'over-oiling' but I am sure (hope that I have set it up correctly...e.g.. with the throttle wide open the two marks on the pump line up exactly. Am I missing something?
I haven't adjusted the air jets yet, I just set them at the obligatory 1.5 turns out. I wanted to know that if I took the tank and airbox off, to enable me to get to the adjustment screws, do I need to block off the air pipe that connects into the tank or just leave it open.
I have to admit here that I did not check the needles when I rebuilt the carbs. Dohhhhhh

Cheers
Mike
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I don't mind dying...I just don't want to be there when it happens!

Anyone please???
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I don't mind dying...I just don't want to be there when it happens!

I haven't even got that pipe, I think you'll find it simply goes 'overboard' so you're fine doing nothing about it with the tank off.

Thanks Dave

Mike
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I don't mind dying...I just don't want to be there when it happens!