Help needed on Carbs related prob or not?

[taylor88]

Hi Meilakj
This is a very informative and interesting thread. I am glad that you have solved the problem and thanks for taking the time to update us
Cheers
Graham

[chrisNI]

Glad you got there....

[ADRIAN H]

Well done.

[Johno23]

I have very similar problems to you,but all four plugs are black. I’ve had the choke plungers done . All jets are std for Z1B and I’ve lowered the needle to slot 2 from 3.
I was wondering about the coils for mine.
I bought the carb kits from Z power, I got the cheaper £17 ones but only used the pilot jet and gaskets, everything else looked ok. Should I get the Keyster kits instead? What I couldn’t really see was the needle jet.How is this removed? Is it just pulled out?

Bike has std air filter and pipes.

[steve452]

The needle jet just pushes out towards the float bowl after you've removed the main jet and holder tube. I just used a wooden drift to push it out with hardly any force. Have just rebuilt all 4 carbs using Keyster kits and the needle jet had me stumped for a while. Good luck.

[zed1015]

I have very similar problems to you,but all four plugs are black. I’ve had the choke plungers done . All jets are std for Z1B and I’ve lowered the needle to slot 2 from 3.
I was wondering about the coils for mine.
I bought the carb kits from Z power, I got the cheaper £17 ones but only used the pilot jet and gaskets, everything else looked ok. Should I get the Keyster kits instead?

I would avoid all carb kits apart from the keyster ones BUT i would still avoid those and use genuine Mikuni where possible.
I would certainly change the pattern pilots back to Mikuni as that could be the culprit.
Unless the carbs are mullered or there's physical damage the only parts that really wear are the float valves, fuel mixture screw tips if over tightened, gaskets and 'O' rings etc.
The main and pilot jets etc don't wear and reported wear and effects of the needle and it's jet are over exaggerated.
All my bikes are running original needles etc and they run perfect.

[Johno23]

Hi All ,

Just an update on carb issue .

finally managed to solve it out , I ordered another set of carb kits , this time I got the Keyster carb Kit which also has the needle jet included in the KIt and not like the Tourmax carb kit .

Re installed carbs and bike now runs pretty well , and all plugs have a nice colour .

I hope this tread helps other guys if they have any issues similar to mine .

Thanks

So do you think it was the the needle jet that was the problem all along?

[Johno23]

I have very similar problems to you,but all four plugs are black. I’ve had the choke plungers done . All jets are std for Z1B and I’ve lowered the needle to slot 2 from 3.
I was wondering about the coils for mine.
I bought the carb kits from Z power, I got the cheaper £17 ones but only used the pilot jet and gaskets, everything else looked ok. Should I get the Keyster kits instead?

I would avoid all carb kits apart from the keyster ones BUT i would still avoid those and use genuine Mikuni where possible.
I would certainly change the pattern pilots back to Mikuni as that could be the culprit.
Unless the carbs are mullered or there's physical damage the only parts that really wear are the float valves, fuel mixture screw tips if over tightened, gaskets and 'O' rings etc.
The main and pilot jets etc don't wear and reported wear and effects of the needle and it's jet are over exaggerated.
All my bikes are running original needles etc and they run perfect.

Great, I will reinstall pilots, but I’ll check needle jets just in case someone has changed them everything else is std. bike has only 27k on it so other jets should be fine, thanks .

[Meilakj]

Hi All ,

Just an update on carb issue .

finally managed to solve it out , I ordered another set of carb kits , this time I got the Keyster carb Kit which also has the needle jet included in the KIt and not like the Tourmax carb kit .

Re installed carbs and bike now runs pretty well , and all plugs have a nice colour .

I hope this tread helps other guys if they have any issues similar to mine .

Thanks

So do you think it was the the needle jet that was the problem all along?

IN my opinion yes , I had done everything that was possible to the Carbs , I dismantled them many times , put them in ULtrasonic bath for a long time . and nothing helped . Only thing that made the difference was replacing the needle jets , and it is now ok .

Were possibly its allways better to replace with originals but the originals are not available anymore from Kawasaki and the ones you will find are old stock and very expensive .

Regarding needle position I would recomend that you put it back on the second one from top if your bike is a z1B and has the latest Z1 Carbs . There is a Kawasaki document showing the different set up of the carbs , I would reconed that you check this carefully and measure all parts and make sure they match just in case something was changed to carbs.

[Johno23]

Hi All ,

Just an update on carb issue .

finally managed to solve it out , I ordered another set of carb kits , this time I got the Keyster carb Kit which also has the needle jet included in the KIt and not like the Tourmax carb kit .

Re installed carbs and bike now runs pretty well , and all plugs have a nice colour .

I hope this tread helps other guys if they have any issues similar to mine .

Thanks

So do you think it was the the needle jet that was the problem all along?

IN my opinion yes , I had done everything that was possible to the Carbs , I dismantled them many times , put them in ULtrasonic bath for a long time . and nothing helped . Only thing that made the difference was replacing the needle jets , and it is now ok .

Were possibly its allways better to replace with originals but the originals are not available anymore from Kawasaki and the ones you will find are old stock and very expensive .

Regarding needle position I would recomend that you put it back on the second one from top if your bike is a z1B and has the latest Z1 Carbs . There is a Kawasaki document showing the different set up of the carbs , I would reconed that you check this carefully and measure all parts and make sure they match just in case something was changed to carbs.

My carbs are all std, although I haven’t checked the needle jet. I assume it is but perhaps not. The needle was on slot 3 which means someone has been in it. I have reset it to the second notch.
So for me to get std needle jets do I have to purchase the keyster full carb kit even though I only need the needle jet, or does anyone know Where I can just get the jets from.

[zed1015]

So for me to get std needle jets do I have to purchase the keyster full carb kit even though I only need the needle jet, or does anyone know Where I can just get the jets from.

I would try Allens performance and buy genuine Mikuni if you have to replace them but as mentioned earlier they rarely need changing and now you have dropped the needle to weaken the mix have you run the bike to see if that has cured the richness.

[Johno23]

So for me to get std needle jets do I have to purchase the keyster full carb kit even though I only need the needle jet, or does anyone know Where I can just get the jets from.

I would try Allens performance and buy genuine Mikuni if you have to replace them but as mentioned earlier they rarely need changing and now you have dropped the needle to weaken the mix have you run the bike to see if that has cured the richness.

I took it out this afternoon. It’s much better than it was but still too rich. I put 7es plugs in it which helped it for a while but eventually the plugs fouled up again......
I did look at Allens, bloody typically they only have two..........
Edit: they seem to have new stock

[Meilakj]

So for me to get std needle jets do I have to purchase the keyster full carb kit even though I only need the needle jet, or does anyone know Where I can just get the jets from.

I would try Allens performance and buy genuine Mikuni if you have to replace them but as mentioned earlier they rarely need changing and now you have dropped the needle to weaken the mix have you run the bike to see if that has cured the richness.

In my opinion and experience the needle jets and needles are something that are not to be ignored. The needles when you are driving are the most mechanical part that is being used in a Carb. Also the same suction that you get when opening the trottle is what makes the needle rub against the needle jet and therefore you will get like a filing effect .
This is my first time experiencing this on a Kawasaki . But I have also found this issue on Hodna CB750.carbs . And changing the needle jets and needles have solved the issue .
Also I recomend changing them.as a set.
With regards to.needle setting this is a.new set up.Kawasaki introduced when they had upgraded the carbs . Even the carb Kit for a Kawasaki Z1 and Z1A are different sets than the Z1B .

[Johno23]

Do you guys with earlier Z1’s get the same problems as the Z1B? Changing from a 2.5 slide to a 1.5 slide is a very big change and riches up the carb a fair bit. Reducing the size of the pilot jet and needle jet perhaps compensates somewhat, but maybe if your chokes aren’t sealing and there is slight wear in the jets this exaggerates the problem far more than it would do on the earlier carbs....................just a theory.

Any way, Allen’s have the needle jets but not the enough needles so I’ll have to go with that for now. See what happens then.........