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Carb question

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DavidZ1R
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Carb question

#1 PostAuthor: DavidZ1R » Tue May 15, 2018 7:22 pm

Going to try and resolve the Carb problem on my z1000 by using compressed air to see if there is a blockage, as a pointer which port feeds the air/mixture screw, I know the inner port is for the choke, so left or right.
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Re: Carb question

#2 PostAuthor: zed1015 » Tue May 15, 2018 8:18 pm

On carbs 1 and 2 = Passage at 4 o-clock is air bleed to emulsion tube and passage at 8 o-clock air bleed to air/fuel mix screw.

On carbs 3 and 4 = passage at 4 o-clock is to air/fuel mix screw and passage at 8 o-clock is air bleed to emulsion tube.

For future reference the passages to the emulsion tube is where you would fit the air corrector jets when running open carbs/pods etc.

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Re: Carb question

#3 PostAuthor: DavidZ1R » Sat May 19, 2018 2:29 pm

Well I give up, while that vicar from the good old US of A, started his speech, I stripped down the carbs, compressed air all the ports and airways, put them back on, balanced took it for a 5 mile ride, still poor at low revs, frustrated with them now, back home just in time for the last couple of minutes of the vicars speech. Going to get another set. :twisted:
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Re: Carb question

#4 PostAuthor: PAULJAC47 » Sun May 20, 2018 9:26 am

:lol: :lol: :lol: lost the will to liive about halfway through,went out on the sunlounger....
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Re: Carb question

#5 PostAuthor: zed1015 » Sun May 20, 2018 2:02 pm

Do you have a pic of the full bank of carbs.
Mainly from the front showing the brass overflow stubs and the blank air screw castings.
Are these carbs from a vac tap equipped bike.

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Re: Carb question

#6 PostAuthor: DavidZ1R » Sun May 20, 2018 6:36 pm

No, they are the correct cars for the bike.
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Re: Carb question

#7 PostAuthor: z1bman » Sun May 20, 2018 9:36 pm

David compressed air will clear loose debris but but these passageways are only the thickness of the wire in a wire brush you either need them put in a ultrasonic cleaner or use a chemical like what i already suggested i know you must be pissed of taking them of & stinking of petrol but abandoning them for the sake of a little bit more time & patience might save you money & buying another set doesn't guarantee they will be any better or need restoring

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Re: Carb question

#8 PostAuthor: DavidZ1R » Mon May 21, 2018 2:50 pm

Paul, I will bow to your far superior experience, I have bought some of that acid, it is last chance saloon with them. Fingers crossed.
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needaz1100r
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Re: Carb question

#9 PostAuthor: needaz1100r » Mon May 21, 2018 6:43 pm

z1bman wrote: buying another set doesn't guarantee they will be any better



Agree with this.
Cheers,

Mark.

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Re: Carb question

#10 PostAuthor: DavidZ1R » Wed May 23, 2018 6:46 pm

I was reading a post on tinterweb about mikuni flat spots, a poster said they had a low revs flat spot, like mine, he said someone had drilled lots of holes in the air box, he blanked them off and cured his problem, my snorkel also has loads of holes drilled in it by some previous person, do you think this could contribute to my problem.
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needaz1100r
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Re: Carb question

#11 PostAuthor: needaz1100r » Wed May 23, 2018 6:58 pm

DavidZ1R wrote:I was reading a post on tinterweb about mikuni flat spots, a poster said they had a low revs flat spot, like mine, he said someone had drilled lots of holes in the air box, he blanked them off and cured his problem, my snorkel also has loads of holes drilled in it by some previous person, do you think this could contribute to my problem.


I'm having a similar problem to yours at the moment, but getting there slowly.

I think the issue is that there are lots of things that can contribute to this problem and all or some probably are at the same time, so yes, your holey snorkel probably is contributing, but don't expect it to be THE cure.

One thing I have been told from a very reliable source, is that the air filter lid should be a good tight fit that seals properly, and that they don't like non-Kawasaki air cleaners, or dirty Kawasaki ones.

This is interesting reading...http://www.mikuni.com/pdf/vmmanual.pdf
Cheers,



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Re: Carb question

#12 PostAuthor: zed1015 » Wed May 23, 2018 7:10 pm

Too much air via open carbs, modified airbox or pods etc will cause a flat spot just off idle at around 2000 rpm and no amount of jetting will fully sort it.
The solution when using bellmouths etc is to fit the air corrector jets i mentioned earlier to richen the mixture in that area .
These are m5 brass grub screws with a 0.6mm drilling that screw into the air bleed to the emulsion tube and were available from LEDAR/Armstrong engineering back in the day.
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Re: Carb question

#13 PostAuthor: z1bman » Wed May 23, 2018 10:47 pm

DavidZ1R wrote:I was reading a post on tinterweb about mikuni flat spots, a poster said they had a low revs flat spot, like mine, he said someone had drilled lots of holes in the air box, he blanked them off and cured his problem, my snorkel also has loads of holes drilled in it by some previous person, do you think this could contribute to my problem.


it will run perfectly without the snorkel its only fitted to suppress air induction & wouldn't cause the problem you have with two cylinders running rich

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Re: Carb question

#14 PostAuthor: PAULJAC47 » Thu May 24, 2018 7:47 am

Agree with comment on snorkel but David has holes in the airbox as well,would blank them off with some gaffa tape,but dont see how would only effect two pots!
PAULJAC47,,,,,"She may not look like much, but she's got it where it counts, kid."

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DavidZ1R
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Re: Carb question

#15 PostAuthor: DavidZ1R » Thu May 24, 2018 4:07 pm

Going to tape the holes on the snorkel, drizzle some acid Paul suggested through the ports, flush them through then see what happens, will report back.
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