GTR 1000 Carburettor

[RFH87_Connie]

That's a nice color!  I rebuilt my dad's and painted it black after he passed away.  We had twin '87s.  Mine was red and his was silver.  Only about 200 apart on the assembly line.  I sold mine last year - didn't need two.

[LT South Africa]

Thanx. I used Titanium from the BMW Pallett. I work for a coach company and we purchase loads of supplies and paint from a local automotive paint supplier. I told them I want to redo my bike. They sponsored me 1 little automotive paint of my choice and all the additional thinners, clear coat, hardener etc...... Made my day.....😎

[MAN OF BLUES]

I think I can construct something like that. Will give it a try. My carbs do look different to yours. But I think it's more to do with your emmision control laws. My basic carbs matches yours. Without those extra pipes...

I'd like to see some more pics of those carbs, from the top down, and from the bottom.. also both sides of the rack, and from the rear...
from what I am seeing in your photos, they are not ZG/GTR carbs, there are no aircut diaphragms located (on #1 & #3)
Early Ninja models did not have aircut valves either, and came in permutations of 32mm, 34mm, and 36mm sizes (that is the actual diameter of the exit port, or Outlet, on the front of the carb)
what does the bore measure on yours?
the Concours had 32mm  CVK32 thruout the length of production.

also, all of your float bowls have the drain screws pointing in the same direction... odd, because iirc on all installations, the screw drain points to the outboard side by half, left 2 point left, right 2 point right...

[LT South Africa]

Thanx MOB. Here are some pics

[LT South Africa]

I managed to do some research today. I have established that the carbs i have come off a Kawa GPZ 600 R

I downloaded the workshop manual and pulled out the spec's for both bikes. Here it is below:

KAWA   –                 GPZ R 600         GTR 1000
                                1988 model                     1988 model

CARBS         CVK 32 MM         CVK 32 MM
MAIN JET              105               125
MAIN AIR JET      100               130
PILOT JET      38               35
PILOT AIR JET      145               85
JET NEEDLE      N27L            N52M
FLOAT HEIGHT      17MM            17MM

The spec's according to the GPZ 600 R is exactly what i have in the carbs now.

The carb bodies both look the same. (To me...)
The carb descriptions are both 32mm CVK

If i look at it from an uneducated perspective. And i mean really uneducated. It would appear to me that if i just change all the jetting etc... to that of the GTR 1000 then i should be okay.

Or will I?

[MAN OF BLUES]

the carbs do differ, the bodies are different... I'm suspecting you do have zx 900 A2 carbs, or zx1000 A1
neither have aircut valves, the differences in the actual jetting, is to overcome losses in accell/decell issues due to this fact, and also the Ninja chaindrive models had a different need than the conni, as they were a bit more fuel consuming...

see the addon, and shoot me a note if it does'nt work, and I'll send the diagrams and p/l's to you...

we did a lot of research on these carbs a dozen years ago, when we were "hotrodding" and modding the bike, trying to pump more fuel into it... funny, because we now find it can excede those gains, with much less fuel, and correct airflow.

check this out, let me know if it doesnt link..

[LT South Africa]

Thanx MOB.

I concluded I have the GPZ 600 R/Ninja carbs based on the jetting.

This is the actual jetting that the carbs have now.


MAIN JET              105               
MAIN AIR JET      100               
PILOT JET      38               
PILOT AIR JET      145               
JET NEEDLE      N760

So effectively. If I change the above to the spec's of the 88 A1 I should be okay.

Is that correct?

   

[LT South Africa]

  I think I might have a mostly complete set of carbs that I would probably never need and maybe an airbox.  I keep reading this but forget to look.
[/quote]

Any chance in you parting with that airbox RFH87_Connie?

I'm just waiting for Man Of Blues to suggest a way forward on the jetting..... Unless you have a full set of all the jets laying around as well.....😎

[connie_rider]

LT, (based on your jets) I think you have the carbs figured out correctly.
Probably the ZX-600 instead of the ZX-1000.

I'm not sure that installing Connie jets in your carbs will solve the issue, but might help.
MOB knows more about that than I do..

Looking at your carbs, the biggest issue is probably that some of the passages are stopped up.
Before I spent a lot of $$ on jetts, I'd do a very good clean.

Here is a EZ way to determine the carb size.
Measure the I.D. and O.D. of the carb ports at the engine side. (shown in photo's 1, 2, and 3)

Connie has a 32 mm carb.
     I.D. is 32 mm (1.260').  O.D. is approx. 38 mm (1.490")

If a ZX-600 has a 32 mm carb,
    I.D. is 32 mm (1.260').  O.D. is approx. 38 mm (1.490")

ZX-1000 has a 36 mm carb.
     I.D. is 36 mm (1.417").   O.D. is approx. 42 mm (1.650")

Ride safe, Ted

[LT South Africa]

Thanx Ted. I will take them off tomorrow (Sunday here) and measure them up. Then of course it needs to be remembered that I am still running on pod filters until I can source a airbox.

 However, when I installed these carbs and replaced the float needles with new ones it ran well. Just not after 6000rpm. When I removed the carbs and checked the float levels they were at 20mm x 3 and 1 x 21mm. Adjusted them down to 17mm. But I did this wrong as I had the carbs upside down. When I adjusted them again with the carbs slightly angled I found them to be 18 and 19mm. So I adjusted them down again to 17mm using the correct method at an angle. I am going to try again and check them with float tubes tomorrow. Maybe then I will get true values........ Maybe I should take the float levels back up a bit. Possibly 19mm...?

At the moment on innitial throttle the engine has a slight miss. Just a little throttle or about 1400 rpm and it's fine. Until about 6500rpm. Then there is a drop off of power and motor sounds like it wants​ to climb out of the frame. It's not the buzz. I know this now from about 4000rpm. It's much worse and difficult to describe. I expect conrods and piston parts to come flying out the engine casing. The engine is still running cool with the temp needle hardly rising. So I'm thinking it's just battling for either air or fuel...... Maybe the slides are not working properly because of the lack of an airbox. ? Or the jet sizes are just wrong because it's not the correct carb again.

PS.... I spoke to the guys who sold me the carb and they say. I asked for CVK and they gave me CVK. Whether it's from a smaller cc bike or any other bike other than a Connie is not there problem. And they don't have a Connie chassis in their yard in any case. So it must be from another bike. But that the way it works here by us.... No ethics.... And a greed for money....

[LT South Africa]

I did measure the carbs and I got the following: see pictures attached.

I'm not sure if I should measure outside to outside or inside to inside.

[LT South Africa]

Another picture

[LT South Africa]

Then, I saw something which probably is a huge factor in the carbs running poor now. When I loosened the drain screws I immediately saw water flowing out. And this happened on all four carbs.

[LT South Africa]

However, once I had the water drained I did a float levels test with the tubes and I am proud to say that all four carbs are spot on......

[gPink]

Think maybe you need to drain the tank?

[LT South Africa]

I did a tank flush....😎

[gPink]

water had to come from somewhere

[LT South Africa]

My filler cap does not seal 100%. I need to get a new seal. I try and avoid the filler cap when I wash the bike. Obviously somtimes I miss.... 😥

[connie_rider]

Your second photo is the one I was interested in.
On that photo, you measure outside to outside and inside to inside.
Measurement's you show,  indicate it's a 32, mm carb.
http://www.zggtr.org/index.php?action=dlattach;topic=21875.0;attach=27919

As you know, it's not a Concours carb, but it is dimensionally correct.

If you have the carbs off now, give them a good cleaning, but clearly water was in the system.

Changing jets/needles etc: let's see what MOB /others have to say.
My guess is changing to connie parts (including slides) will help but not be exactly correct.
Air box will also help.

Ride safe, Ted

[LT South Africa]

Thanx for the help Ted. I did a complete cleanup again and so far its feeling better. 

I unfortuanately have to hold on getting the jets until I can afford it. But I won't move forward until I hear whether I should go in that direction from the other guys....

Leonard