So, I have this issue where my 92 zx7 will start up and run fine for 10 mins but once I get to a stop, it dies... I wait a few mins then I can go for a few more minutes and same thing. I pulled the new plugs I bought and they're black.
I assume this is due to an overly rich mixture so, why ? One thing I noticed is that this new motor has two allen head bolts on the cylinder head cover which in the manual seems to feed air to the top two hoses on my carbs.... the thing is, on my bike those two hoses aren't connected to anything. Is this why my bike is gradually running itself too rich till it dies ?

Here is a pic of what I'm talking about ....



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[IMG]local://upfiles/2369/7B3A9CFE0C4B4B018636355CDDEB927C.jpg[/IMG]

[IMG]local://upfiles/2369/9E8A3E0536334947B149B1FAF06F00E6.jpg[/IMG]

 

I am not sure about those 2 hoses in your first pic and both of my bikes do not have any hoses coming out of the valve cover and connecting to the carbs.

What mods do you have, exhaust, air filter and jetting if any?

What size jets, mains and pilot?

Pic 2 has the float bowls off have you thoroughly cleaned your carbs, needles and jets?

 

My bike is totally stock other than a yosh pipe. Now that my carbs are apart, I need to know how to setup my pilot jet screw. Is there anywhere with info on how to do that ?

 

alright.... I cleaned the float boal, jets and everything in the bottom including reset the pilot screw to 3 full turns as I'm running an aftermarket exhaust.

SAME DAMN THING..... drove it till it got hot.. and it wouldn't do anything more than sputter... turned it off... waited 4 mins...it then started gradually...then I drove it home.

SOMEONE PLEASE HELP !!

 

Sounds like your are definately flooding her out. Running way rich... Someone took off the emissions crap... Usually when you do that, people rejet also, cause it does change your A/F ratio... Are you sure the bike is stock in the carbs? What size jets are you running? Are the floats adjusted correctly?

Are you running a hi flow air cleaner? I am not sure on how many turns out.... I am currently set at 2 on my 10.... How many turns where they out b4?

There's a couple of real good zx7 guys on here. Be patient, and they'll get to ya

Since you all ready fouled those plugs, I would change them out also.... Let us know , man...

And if you have a vacuum leak, it could cause a rich mixture also... At night on a high rev, do you have flames out the exhaust? does the bike pop or back fire at all on decel? Make sure whoever pulled off the emissions carp, that all the hoses are blocked good, and you have NO vacuum leaks. Check the carb boots also....

 

I am assuming that you mean the Air Fuel mixture screws, AF.
Is your yosh a full system, header and pipe or stock header with yosh pipe. The second would not require adjusting the AF or re-jetting. 3 turns out sounds like a lot. 1.5 maybe 2 sounds more correct.

What size pilot jets and what size main jets do you have? What jet kit do you have?

 

i just recently pulled my engine out and those hoses are connected to the top of the head(where you guessed it at first...i was/am haveing that problem also, she runs rich and i get always got flame every now and then. personally i'm going to re-do those jets cause they are the stock ones...they might be alittle old to be running now(in my opinion). and also i took the bike from 4000 feet above sea level to about 150 feet/sea level(japan) ran good until i brought it back to the 4000 area again. i think the only difference between the 92 and 94 was the frame and bigger carbs for the engine

 

also it's the two hoses on the left and right of that valve that is connected to the heads

 

a local kawi guy says that the hoses on the top of the carbs SHOULD be hangin down un connected. He says there are two types of breathers. One is crank case to air box the other is cylinder head to those tubes I have. Since I have
a crank to airbox setup, my other ones don't connect to anything. I don't know if my exhaust is full yosh or just a can but I will try 2.5 turns out instead of 3 to see if that does anything... My pilot screws have o-rings that I will replace tomorrow as well since the carbs sat dry for a couple years and one of them cracked when putting the carbs back together.
Tonight when I was trying stuff out and as usual it sputtered and died once It got hot and I noticed the rad's overflow bottle was bubbling.. Is that normal or should it be cooler than that ? I will say that once the revs get up the bike seems to run fine but once they get low the sputtering begins... ofcourse only when it's hot.

I'LL LET YOU ALL KNOW.... BUT PLEASE KEEP THE ADVICE / QUESTIONS COMING.

Chris.