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Fast idle/choke

Fri Jun 23, 2006 10:38 am

well the Z has a fast idle chokey thing, what is it?
if i was to use it as a means to speed the idle up for short periods, (like a few bendies etc) to stop the rear locking under compression.
would it be making the bike run rich? or is it just like holding the throttle open a bit?

remember, Z's are fuel injected...

Fri Jun 23, 2006 10:49 am

...well my 05 ZX12R is injected to but it still has a fast idle circuit (cant call it a CHOKE on EFI can we?)
I would GUESS from the amount of raw fuel coming out the ars when its warm that it actually richens it up too....

Fri Jun 23, 2006 11:27 am

it's like a automatic choke, letting more air in to put more fuel in to warm it up, should only happen for a little while

Fri Jun 23, 2006 12:22 pm

My plugs fouled once when my choke cable was sticky.... meaning the choke was permanently on..... I think this would only happen if you rode with it permanently on....

Fri Jun 23, 2006 12:26 pm

Duane wrote:it's like a automatic choke, letting more air in to put more fuel in to warm it up, should only happen for a little while


nah, no auto choke on these beasties, it has a lever on the bars.

Fri Jun 23, 2006 12:37 pm

Wattie wrote:
Duane wrote:it's like a automatic choke, letting more air in to put more fuel in to warm it up, should only happen for a little while


nah, no auto choke on these beasties, it has a lever on the bars.


Yeah I wasnt very explicit was I
The ZX12R has teh same lever as the Z1000 is what I meant to say.

It IS a choke, but not as we know it Jim
And make sure to beware of Klingons around Uranus

Fri Jun 23, 2006 1:50 pm

My manual says it is only to be used on start up. It could adjust the fuel air ratio, I personally would not use for general riding.

Fri Jun 23, 2006 2:03 pm

Most EFi bikes will have a seperate idle screw. On the Hornet I could probably reach it on the move with practice, or a two second job when pulled off the road. I am sure the Z will I have a similiar set up. Have a look on top or below the throttle bodies and see where the idle screw is located and use that if you wanna up the idle.

Of course, as most people are unaware, The Big K have been fitting slipper clutches on their sports bikes since oh .......1989!!!!! :wink:

So the chances are, that your ZX9 based engine in your Z1000 will have one of these so called "Back Toorque Limiting Clutch" or as they call them in modern day marketing speak, "Slipper clutch".

Now if you do have said "Back Torque limiting Clutch" then you can adjust it so it ramps up more or less. thus making it operate zachary like an 05 636's slipper!!!! Thus negating the need to run your idle so high! :wink:

Fri Jun 23, 2006 2:15 pm

No slippers on a Zthou or ZX12R unfortunately Striker.

When I was searching for one for the 12 I got told (by STM) that they make them for the 10 and 6 but not 9 and 12 ... bummer :oops:

BUT like you advised above, I was told to turn my idel up o nthe track to limit decompression locking.... but seeing as how that would be about 5k on the 12 I am tempted to try it.... :lol:

I dont know where yours starts to decompression lock up Wattie but it MIGHT work for you, jsut remember to turn the idle back down on the road :shock:

As I said B4 (and Hoffy too) I would NOT use the choke lever we both have (on EFI :lol: good shit Kwaka) to up the idle....

You can do a Casey Stoner (Micky D did it too) and just ride the clutch into the corner a bit. When it happens to me (lock up on track) I reclutch and try again, the time it takes normally gives the motor enouf t oget back down to a "reasonable" speed....

Fri Jun 23, 2006 2:35 pm

frogzx12r wrote:No slippers on a Zthou or ZX12R unfortunately Striker.

When I was searching for one for the 12 I got told (by STM) that they make them for the 10 and 6 but not 9 and 12 ... bummer :oops:

BUT like you advised above, I was told to turn my idel up o nthe track to limit decompression locking.... but seeing as how that would be about 5k on the 12 I am tempted to try it.... :lol:

I dont know where yours starts to decompression lock up Wattie but it MIGHT work for you, jsut remember to turn the idle back down on the road :shock:

As I said B4 (and Hoffy too) I would NOT use the choke lever we both have (on EFI :lol: good shit Kwaka) to up the idle....

You can do a Casey Stoner (Micky D did it too) and just ride the clutch into the corner a bit. When it happens to me (lock up on track) I reclutch and try again, the time it takes normally gives the motor enouf t oget back down to a "reasonable" speed....


Just check on that back torque limiting thing as I am confident that your Z has this clutch fitted as standard. Kawasaki have used these for years, but only now do people realise how they work, and the fact they can be ramped up more. As an example, ZXR750 from 1989-1994 has them, ZX7R's have them, and ZX9R's have them, so as your donk is derived from that, I would be surprised to find out that it is not! Check the manual, don't listen to some of the gumby techo's in Kawasaki dealers, as a lot of them don't even realise what they are. :roll:

Fri Jun 23, 2006 2:41 pm

The 7's definiitely did (I got one), but the 9's ??
Hey anything is possible but.

Fri Jun 23, 2006 3:39 pm

I had the old 9's clutch apart in many, many pieces, and I didn't see any way that it could've been made to work like a slipper clutch.

It's definitely been discussed that you can make the 7's clutch into one though.

Sat Jun 24, 2006 9:18 am

Strika wrote:Most EFi bikes will have a seperate idle screw. On the Hornet I could probably reach it on the move with practice, or a two second job when pulled off the road. I am sure the Z will I have a similiar set up. Have a look on top or below the throttle bodies and see where the idle screw is located and use that if you wanna up the idle:


You are right Strika its located under the injectors in the centre...
It is an adjustment screw similar in size & shape as a carb one

Would be a bit of a worry trying to get a gloved hand in there while on the go... spose would be possible but would you risk it?

Sun Jun 25, 2006 10:03 pm

I know the fast idle lever (that uses a choke symbol) on EFI Suzuki's simply holds the throttle off the normal stop. For a while I had mine adjusted so that full on = approx 6000 rpm, it was my crude cruise control.

(I've since wound it back to 2000 rpm and use when doing any carving or track days as it makes off - on throttle transitions smoother. )

It doesn't adjust the mixture at all, and the owners manual still has instructions in it that treats it like a choke / enrichening circuit.

Mon Jun 26, 2006 11:05 am

yep, all those levers on EFI bikes do is bring the idle up higher.

the lever doesnt control anything to do with cold start enriching, that all comes from the bikes coolant temp sensor (CTS). once that is up to temp it runs the mixtures normally no matter what the lever/idle is set at


damn, i wanna inject my bike now :?
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