Mixture adjustment?

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Taipan
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Mixture adjustment?

Post by Taipan »

Hi All
My bike is running rich on idle. So I took my trusty angled screwdriver down to the bike to see what the mixture screws are set at, and of course found a bloody big frame spar in the way. #-o So I may as well adjust it using my gunsons gastester (be nice to actually use some of the crap I buy for once :roll: :D ). So how do you adjust them. Is it a tank off and rig up a temporary fuel supply? I assum ethe mixture screws are on teh undersid eo fteh carbs? Any tips, do's or don'ts?
Many thanks.


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yorkie
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Re: Mixture adjustment?

Post by yorkie »

This thread will help you lift the carbs off
http://www.bikersoracle.com/zx9/forum/s ... php?t=2375
then adjust the pilot scews to 2 turns out from gently fully in, these are forward of the float bowl drain holes and could be hidden under a plastic bung, if so prise out.

I keep trying to remember where your located, as you've not put it on your profile.


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Taipan
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Re: Mixture adjustment?

Post by Taipan »

yorkie wrote:This thread will help you lift the carbs off
http://www.bikersoracle.com/zx9/forum/s ... php?t=2375
then adjust the pilot scews to 2 turns out from gently fully in, these are forward of the float bowl drain holes and could be hidden under a plastic bung, if so prise out.

I keep trying to remember where your located, as you've not put it on your profile.
:TUY
I must have missed that bit when I did my profile? :o But I've done it now. :)


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KD
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Re: Mixture adjustment?

Post by KD »

kwaka's generally seem to run rich. But not too rich (a blackening on the exhaust pipe)... The ram air effect sorts that out.

To be honest I havent had to touch the pilot screws in general use since first owning one in 1995.... Becareful!!!

Actually the only time was on the B2 when i fitted the dynojet kit to it.

If i was was worried.. I would generally go for a blast and then pull the plugs and see what colour they are, and go from there.


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Taipan
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Re: Mixture adjustment?

Post by Taipan »

It seems fine when actually riding, just a bit fluffy coming off idle. Also if you rev it the revs drop and take a moment to rise again which normally indicates a rich idle?

Before i did the float bowl modifcation thing it didn't do this, so I'm wondering if someone richened the idle up to try and compensate for the problem?


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KD
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Re: Mixture adjustment?

Post by KD »

Have you tried raising the idle setting a little :?:

and see if the problem clears that way... may save you a heck of a lot of time


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yorkie
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Re: Mixture adjustment?

Post by yorkie »

Basildon, a bit to far for me to drop by and help personally I'm afraid.

Set the idle slightly higher as said by dave, normal is around 1100 to 1200rpm.


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peasngravie
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Re: Mixture adjustment?

Post by peasngravie »

And make sure you have no air leaks in the ram air system, Air box, carbs or carb take off's. have had that before.

Coming back up the road from a certain party last year, the bolt i had jammed in the pipe coming off the carb balancing hole under the carbs came out. It was very reluctant to tick over properly after a good kicking and coming to a stop the revs would drop like you say(Below idle)Then rise back up to a stumbly normal idle.

Still kinda went OK though, Mind you i just asked about this, Mines is still very spluttery when pulling away #-o adn stinks o petrol when first started.


Lube me up - I'm coming through!
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Taipan
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Re: Mixture adjustment?

Post by Taipan »

Hi All

The idle sped is ok once its settled, but if you rev the bike up as the revs drop it will idle really low for a second or three before working its way up to the normal idle speed. typically this means its running too rich and i'd like to address that and of course play with the gas tester. :D

Peasngravie I had a similar problem on a bike once and it was a sticking float messing up the float heights.

Yorkie, i appreciate the thought. :)


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