awhite
|
| posted on 23/3/07 at 01:00 PM |
|
|
Bike Carb Problems
Hi,
I need some help setting up bike carbs.
Carbs are Keihin CVK carbs with vacuum slide. I have a ZX9 fuel pump which pumps 2-3 psi. idle screws are 3 turns out have tried with a washer under
needle but it almost undriveable below 3000rpm it misfires all the way with a washer in, without washer in there are 2 spots that it misfires before
3000rpm. Getting really fed up now.
It has main jets of 170 from DGAS.
Someone else with Bogg bros carbs blocked the air bleed jet off (in the middle at front) and had 165 jets fitted. With air thing blocked or not
doesn't make much difference. Float levels are all pretty much the same.
I rang bogg brothers but they want £60 plus p+p to set them up probably the same as i have.
I've temporarilry disconnected the vacuum pipe on dizzy this wouldn't do it would it?
Any help very much apprecaited this is driving me mad.
Thanks guys,
Andy
[Edited on 23/3/07 by awhite]
|
|
|
|
|
BenB
|
| posted on 23/3/07 at 01:08 PM |
|
|
Are they synchronized? Surely you need to concentrate on synch and idle first (after all there shouldn't be any flow through the main
circuit)... Then when they're all working, work out what jets and washer positions you need for the main jets.....
I found a Colortune and Carbtune combo sorted out my idling and low speed fluffing. I still need to rejet- but thats because mid and high rpms goes
too rich..
|
|
|
awhite
|
| posted on 23/3/07 at 01:11 PM |
|
|
Sorry forgot to mention that i synced the carbs using a syncrometer. The idle is smoothand it seems to be ok revving in the garage but when i drive it
under load it farts about, strangely when i rev it in the garage after driving it farts but not when i first start it.
Grrrrrrrr.
|
|
|
se7ensport
|
| posted on 23/3/07 at 01:13 PM |
|
|
I'm running the same carbs at the moment, came set up from BB. No stutter and very smooth below 3000, from what I could find out the jets are
drilled out slightly rather than replaced (guess it's cheaper for them).
unfortunatley I can't offer advice on how to set them up, but for £60 it's probably worth it.
however mine are running a little lean, don't suppose you have a diagram for them?
|
|
|
awhite
|
| posted on 23/3/07 at 01:16 PM |
|
|
I've got a diagram somewhere i'll dig it out. Do you have the air jet blocked off?
Thanks,
Andy
|
|
|
BenB
|
| posted on 23/3/07 at 01:16 PM |
|
|
A rich mixture gets worse as the carbs heat up.... Sounds like it's running rich in parts of the range.....
If its only £60 to get sorted I'd throw some money at it....
|
|
|
awhite
|
| posted on 23/3/07 at 01:20 PM |
|
|
For a diagram goto www.kawasaki.com and goto owners manuals then goto Ninja ZX6. The neventually carburettor should show you wahat you need.
|
|
|
se7ensport
|
| posted on 23/3/07 at 01:22 PM |
|
|
Re: air jets
if you mean the rubber tubes that exit at the top between 1&2 and 3&4 bodies, then no, mine just go to atmosphere.
Hang on, I think you are referring to the jets that you can see from the airfilter side, again mine are unblocked.
Mine spit and stutter when cold if using the choke, but within 2mins they are warmed up and ready to go, does you choke definitely close all the way?
|
|
|
awhite
|
| posted on 23/3/07 at 01:37 PM |
|
|
Thanks yeah i meant inside the air filter side when you pull the trumpets out.
I've about had enough of them i've been faffing for 3 weeks. Might go back to the DGAV its a waste on my engine but at least i know it
works.
Maybe i'll try the colourtune method to make sure its not idle mixture affecting it. More money! 
|
|
|
se7ensport
|
| posted on 23/3/07 at 01:42 PM |
|
|
quote:
Originally posted by awhite
Thanks yeah i meant inside the air filter side when you pull the trumpets out.
I've about had enough of them i've been faffing for 3 weeks. Might go back to the DGAV its a waste on my engine but at least i know it
works.
Maybe i'll try the colourtune method to make sure its not idle mixture affecting it. More money!
When they work they really do work well, mine are better than 45's that had been set up! personally I'd take the hit in my pocket now and
get BB to sort, I've found them very helpful with advice as well.
Ps Thanks for the diagram info, Kawasaki manuals are bloody useful!
|
|
|
will121
|
| posted on 23/3/07 at 03:25 PM |
|
|
you say at the beginning that you have removed the distributor vacuum advance, as it revs ok under no load, it may be having an adverse effect with no
vacuum or TPS when engine put under load, I assume your manifold now has no vacuum take of tappings?
|
|
|
jacko
|
| posted on 23/3/07 at 03:35 PM |
|
|
Hi i have zx9r---E carbs fitted there set as
2 washers under the needles
airscrews 1 turn out
airholes blocked as you metioned
main jets drilled out to 1.7
fitted to a pinto 2.1
set up by Bogg Bros on rolling Road
Jacko
PS what engine have you got the carbs on ? if you fit bike carbs you realy need a modifide dizzy or megajolt on a pinto
[Edited on 23/3/07 by jacko]
|
|
|
se7ensport
|
| posted on 23/3/07 at 04:16 PM |
|
|
Jacko- what kind of bhp are you getting out of your set up? by getting it rolling roaded did it release more or just make it smoother?
Cheers
Alex
|
|
|
jacko
|
| posted on 23/3/07 at 04:22 PM |
|
|
Hi my engine is not standard but the carbs gave me about 30-35bhp over what i had when it was r/roaded it had 140 at the rear wheels pounds for
power you will not go wrong with bike carbs
jacko
|
|
|
awhite
|
| posted on 23/3/07 at 05:41 PM |
|
|
Had some advice from the guys that sorted my manifold. Going to play with timing and make up something to take vacuum advance.
Andy
|
|
|
jacko
|
| posted on 23/3/07 at 08:07 PM |
|
|
Hi i tryed to do the vacuum advance using one way valves etc but it will not work the dizzy just,s pulses . you need a modifide dizzy or megajolt i
got a modded dizzy from H&H ignition solutions
Jacko
|
|
|
DarrenW
|
| posted on 23/3/07 at 10:58 PM |
|
|
Vacuum - isnt that some old fashioned attempt at ignition load mapping??????? Go for megajolt - you know it makes sense. Graham is secretly yearning
for a MJLJ conversion - he just doesnt know it yet.
Why go all modern with bike carbs and stick with the spinny bits.
|
|
|
TangoMan
|
| posted on 24/3/07 at 09:22 AM |
|
|
There sits a converted man
He does have a point though!!
I can see Darren will be going the full monty with Megasquirt next winter 
It sounds that it is probably too rich. Can you not drop the needle any. Mine had a spacer under the needle which could be moved above the clip to
lower the needle.
The main jet sounds a bit big but this shouldn't come into effect until about 2/3 throttle.
The primary jets are probably too big so try getting some smaller ones. These control the transfer from idle to 1/4 throttle running.
Or solder them up and get some needle drills.
Stick with it because they will be worth it in the end. £60 doesn't sound bad if you are out of ideas but try what I have suggested first.
Summer's here!!!!
|
|
|
bricheun
|
| posted on 1/4/07 at 03:05 AM |
|
|
Check needle holder - maybe lodged too high allowing needle to falter. There are grooves which the needle holder must fit. It is easy to push it down
in the wrong position assuming it is securely down.
Also check your diaphram.
It happened to me once and the symptoms are the same!
[Edited on 1/4/07 by bricheun]
|
|
|
