As the title suggests, I'm trying to get my idle mix right and failing miserably.

I keep fouling plugs, initially they were just black. I stripped down the carbies, gave them a nice bath, put them all back together and they bike ran much better - except at idle.

So now when I foul plugs, they come out nicely brown, but with a wet layer of oily fuely gunk on top. She runs beautifull from 3k -12.k but below three she tends to run choppy, and the front cylinder is a bit intermittant.

If I'm stuck in traffic or at low speed she starts to struggle with idling and I have to rev her to keep her alive.

So back to the air screws. I'm trying to follow the procedure - MC21 + TA22B. I take the screws to 1.5 turns out. then try to adjust from there. The only problem is that nothing happens when I turn. All the way in, or completely removed seems to make no difference.

The previous owner fitted a Tyga System and removed the airbox for pod filters. I won't go into jetting, but just say stock slow jet, slightly uprated main jet and power jet still seems active.

I have done the wiresplice and that went great at operating Revs but this niggling Idling/Fouling problem won't go away.

I have a computer in my garage and I've currently got the tank and fairings off cleaning, poking and prodding so any suggestions would be great.

I've got her running so nicely it would be a shame to have to take her to a mechanic for something as mundane as idle problems.

Cheers

Clancy

have you checked air jets arn`t blocked, air hoses fited correctly.
When i was sorting jets when i had much to big mains in air screw did nothing. but if plugs arn`t to bad could be the air deliverey slighly blocked.
Have you taken the air srews out and checked for wear .
You could also check oil pump adjustment.
I`d take carbs off first clean right out check for blockages,wear.

Thanks for the response.

Jets are all clean.

I've had the carbs off the bike. I separated them, took the float bowls off and gave them a petrol bath. Mid range and top end were heaps better when i put them back on and as I said, the plugs look a lot better now.

How do you check for wear on the air screws? Which parts wear?

I had them out today, there's a couple of marks on the sides but that's it.

The ends taper, but the tip is flat. Is this normal, or should they be more needle like.

As far as air hoses go, I have recently replaced them as per the illustrations. Unfortunately the cross piece was broken so I have emulated it with two T pieces to make an offset cross. All hoses that would normally go the the air box now just vent to atmosphere.

Oil pump *looks* ok. I didn't check it specifically as it seems to be coming on with the throttle just fine.

Maybe I should disconnect it and try some premix.

All other suggestions are welcome - She's currently sitting tank off in the garage so I can get straight back into her.

My bike won't idle without the hose connected to the airbox thingy..

you need to get the proper t piece and y piece as the have jets in them and are important

Hmmm,

Interesting.

Can I still get them genuine? What should I do about the hoses that would normally got to the airbox, since I no longer have an airbox?

Thanks again.

Clancy

try here [company name removed by Admin] if you can get them new they can order from japan they have them as avaliable $26. or put a post here in clasifieds shore someone using hrc jet kit will have standard + piece lying around.

hoses for airbox should be right not conected im shore there just breather for emmision (minimise gases into air) i think once you put + piece on you should be right. just check jetting once fitted as will have different air flow

Thanks mate.

Site looks great. I'll probably just order new ones since they're expensive but not too expensive. At least this means there will be more of them floating around.

Just to be VERY VERY sure.

[Reference removed by Admin]

says the airscrews are number 12, but the manual on this site says they're number 9.

I've been working on number 9. This is in the right hand side of both carbs with a spring in the hole.

Please tell me this is right.

It's worth getting the right ones.

Andy and myself spent some time on the dyno with different X and Y's and they do alter things rather alot.

I've got a few here but with different sized holes but now I can't remember what stock was.

0.6mm rings a bell.
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If I have to take the carbs off once more...

no number 12 is set screw (to balance carbs) number 9 is air srew not avalable

Excellent.

So I'll just order a new one I think. Pretty sure my Y piece is OK, but I'll check before I order.

As far as the balance screw goes, I'm having some trouble with that too. Of course with the front cylinder not running properly at idle it makes it very hard to balance. I did separate the carbs so now it's a bit out.

Does anyone have tips for balancing the carbs properly and should I attempt to do it before or after I get the air screws right.

Also, when I say the front cylinder doesn't run properly, the exhaust is still coming out, puffy but very cold in comparison to the top cylinder. Also, the bike will idle with just the top cylinder but certainly won't idle with the front cylinder. If I hold it above 3k RPM and disconnect the HT lead on the top cylinder, the front cylinder can keep the engine ticking over no probs.

This is what makes me think the mix is screwed up at idle, but if it means something else, please enlighten me.

Thanks again for all the help so far guys.

The first thing I also do is have a look up the exhaust port no matter whats going on.
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If I have to take the carbs off once more...

That's just a matter of taking the exhaust off right?

Or do I need to take the power valve off too?

Well I took the exhausts off today and had a look. Certainly looks like exhaust gasses are skipping past the rings. I'm hoping it;s just wear and not something that has failed.

I guess you don't believe people when they say "it had a top end rebuild 1000km ago"

I will post the pics in a nice new thread about my rebuild.

I think it might be time to register....