So I got the new engine fired up, YB cossy on ZX9Rs..
My AFR says I'm running lean at idle and adjusting the pilot screws underneath seems to do nothing?
And when I give it a lot of revving the sliders dont move? just stay well and truely at the bottom..
Any tips peeps?
Whats the proper procedure for cold starting bike carbs?
Cant take it for a drive yet as I have no steering....
No RRs in Ireland will touch bike carbs on a car engine so all pointers possible please
I have checked the flow with a meter and all are bang on with each other.
[Edited on 5/1/11 by Craigorypeck]
Hi what model zx9r carbs do you have ?
Have you balanced the carbs ?
the screws under the carbs are used for fuel at tick over then the main needles/ jets take over as the revs come up
Have you striped and cleaned the carbs?
are the slides smooth to lift with your finger ?
is it all the slides that don't move or just 1 or 2
has the manifold got a good seal to the head no air leaks any were
Jacko
Hey.
I have C1 models.
Carbs balanced with a synchronizer, didn't need much, all were pretty bang on equal.
There was a small blow from the exhaust near the afr sensor,must have been letting air in maybe. Patched that up and it now works better and the screw
adjustments have an affect on the reading.
Carbs were completely stripped and meticulously cleaned in thinners.
The slides lift and have a slight resistance going up and down from the air above and below the diaphragm, when rebuilding- one didn't have any
resistance and snapped shut very fast. This was because the diaphragm wasn't seated correctly under the cover. All are equal now.
Started upain a while ago and one slide moved ever so slightly but I was near 5000rpm before it moved.... Don't really wanny be up round there
too much on a fresh build!
Manifold face is true and has a cometic gasket on it. Fluro lined silicone hose is jubilee clipped up nice and tight. Defo no air leaks.
At what rpm should they start moving??
[Edited on 5/1/11 by Craigorypeck]
Not the best film but shows that the sliders should move from quite low revs;
here
Here's mine
http://www.youtube.com/watch?v=Apqs5EqZuOo
quote:
Originally posted by deltron63
Here's mine
http://www.youtube.com/watch?v=Apqs5EqZuOo
Mine are ZX6R with 165 main jets on a 1.8 zetec.
Are you using a bike fuel pump? it makes all the difference
quote:
Originally posted by deltron63
Mine are ZX6R with 165 main jets on a 1.8 zetec.
Are you using a bike fuel pump? it makes all the difference
Did you really use thinners to clean them? (cringe)
I used thinners on my first set and they ended up in the bin! It eated away at the ali and stripped all the rubber bits off.
The sliders not lifting is probably down to the flange at the top not sealing properly, however this rarely affects all 4. The thinners hasn't
destroyed any of the seals has it??
All rubber seals, washers and diaphragms were removed.
Only the bodies were wiped with thinners and the brass bits steeped.
The diaphragms are all seated properly around the circumference....
Do you think a previous owner may have had stronger springs put in for some reason??
[Edited on 5/1/11 by Craigorypeck]
[Edited on 5/1/11 by Craigorypeck]
Am in the process of ordering bike carb set up for my cvh from bogg bros,when i mentioned final tuning after set up,they recommended holeshot racing
in co.down,after contacting them they have already fine tuned a few other bike carb set ups,and would be worth a call,
As coozer said, if the slides arnt lifting them its probably the diaphragms not sealed properly in the top. Remove them and put a smear of rubber
grease around the sealing edge then try it. I had loads of trouble with mine.
Have you blocked off the vent pipes aswell or are they open?
quote:
Originally posted by uel90
Am in the process of ordering bike carb set up for my cvh from bogg bros,when i mentioned final tuning after set up,they recommended holeshot racing in co.down,after contacting them they have already fine tuned a few other bike carb set ups,and would be worth a call,
quote:
Originally posted by Danozeman
As coozer said, if the slides arnt lifting them its probably the diaphragms not sealed properly in the top. Remove them and put a smear of rubber grease around the sealing edge then try it. I had loads of trouble with mine.
Have you blocked off the vent pipes aswell or are they open?
You could try giving Bogg bros a ring they are helpfull guys UK no 01944 738234
on my zx6r carbs is a small O ring next to the diaphragms easy to forget and loose with the tops off.
I had a chat with them ages ago... They suggested the ZX9R carbs and the 180 mains I have in with the air correctors blocked up.
quote:
Originally posted by woolly
on my zx6r carbs is a small O ring next to the diaphragms easy to forget and loose with the tops off.
did you make sure you didnt loose the little o rings the screw driver is pointing at. they make the seal that lifts the diaphragms
Mine have the ring as part of the diaphragm.
You can see it in the pic, just about
This is how I've put the needle in.
Diaphragm - washer below clip - clip - washer above clip - spring seat
Is that correct?
ashg you said it so much better than me
So I am missing those little devils???
edit
Nope.. the rubber washer is not needed as the rubber bit that sticks out of the diaphragm fits the profile of the carb perfectly.. No room for that
rubber washer
Care to comment on the arrangement of the needle assembly?
[Edited on 6/1/11 by Craigorypeck]
My zx9's have the the seal moulded into the diaghram and dont have the
small o rings.
I had problems getting mine to seal and lift when i touched the throttle
but perseverence and a touch of sealant got it sorted.
Oh,by the way,it might rev with no vacum to lift the slides but it won't drive at all.
I know this because i tried it.
Andy
quote:
Originally posted by lotusmadandy
My zx9's have the the seal moulded into the diaghram and dont have the
small o rings.
I had problems getting mine to seal and lift when i touched the throttle
but perseverence and a touch of sealant got it sorted.
Oh,by the way,it might rev with no vacum to lift the slides but it won't drive at all.
I know this because i tried it.
Andy
To check the seal all you need do is push the slides up to the top
and let them fall back down.
You should feel resistance on the way up and hear the air being forced out,
then they should fall slowly back to the start position.
They should all be exactly the same.
The fact that they dont move with the engine running,tells me that they
are not sealed.
Bike carbs are better than dcoe's in my experience.
(just my opinion though,you must understand
)
Andy
quote:
Originally posted by lotusmadandy
To check the seal all you need do is push the slides up to the top
and let them fall back down.
You should feel resistance on the way up and hear the air being forced out,
then they should fall slowly back to the start position.
They should all be exactly the same.
The fact that they dont move with the engine running,tells me that they
are not sealed.
Bike carbs are better than dcoe's in my experience.
(just my opinion though,you must understand
Andy
sealed all the edges with grease and they seem to be working better now...!
Thanks lads!
Do you have any photo of your car / engine what mods have you done to run the engine on carbs
Thanks Jacko
quote:
Originally posted by jacko
Do you have any photo of your car / engine what mods have you done to run the engine on carbs
Thanks Jacko
Had a look at the carbs and it would look like the throttle needs to be shut so the fuel is drawn in through the choke??
As my car is only out at the weekend the chambers and runners will be completely dry so needs quite a bit of cranking to wet the cylinders via the
smaller suited to motorbike choke feed.... so
Has anyone done away with the manual choke, tapped 4 jets into the runners, piped up to a switchable valve fed via the fuel pump supply. So before
cold start, cabin switch on 5 secs before crank to prime, left on for a min to stop stalling???
Just a thought...
Hi Mate if i was you remove the fuel pump and regulator you have and fit a big bike ie zx9r pump if you do a search you will find a lot of ppl have
problems with the set up you have,
I only use my car on weekends not all of them and all i do is turn the ignition on [ fuel pump ] then pull the choke start the engine choke off
That's why you want a electric ticker bike pump
Jacko
Ps your car / engine look very very nice
[Edited on 8/1/11 by jacko]
Thanks
I had considered the matching pump. Prob still will.
When the choke is out is the fuel allowed into the runners before starter is engaged???
Or does crank suction draw the fuel in??
[Edited on 8/1/11 by Craigorypeck]
quote:
Originally posted by Craigorypeck
Thanks
I had considered the matching pump. Prob still will.
When the choke is out is the fuel allowed into the runners before starter is engaged???
Or does crank suction draw the fuel in??
[Edited on 8/1/11 by Craigorypeck]
quote:
Originally posted by jacko
quote:
Originally posted by Craigorypeck
Thanks
I had considered the matching pump. Prob still will.
When the choke is out is the fuel allowed into the runners before starter is engaged???
Or does crank suction draw the fuel in??
[Edited on 8/1/11 by Craigorypeck]
Bike carbs are modern SU carbs [ suction units ] so working on that it is the cranking vacuum that sucks the fuel though
or so i am make to believe
Webbers have a pump that just shoves fuel in whether they need it or not thats why they have to be set up spot on
Bike carbs only use the fuel the engine needs
I bet you know that all ready
Jacko
As said, bike carbs don't need the throttle pumping thing since it won't do anything anyway. Some of them have a built in wax stat on them that controls the choke, and some have a throttle slide that connects all four together to move the chokes in unison. I'm not sure which yours should have, but it'll probably be one or the other. Once it's connected right, it should just be a case of pulling the choke cable out, if you have one, and away you go. I could start my blackbird Indy as low as -5C with just a bit of choke and turning the key.
Whats the issue with using a red top and filter king??
surely it would be ideal set at 2.5 - 3 PSI
Bike carbs only require around 1.5 psi,any more and you start flooding the
carbs/blowing fuel out through the breather pipes.
As Jacko pointed out,the best thing is a bike
fuel pump.
Andy
[Edited on 9/1/11 by lotusmadandy]