[RyanZ-400]

:?: Hi Everyone!
A few weeks ago I installed the Alba K&N filter kit, took off my snorkle and drilled a couple of holes in the airbox. I also drilled out my exhaust (pea shooter). I went to my local motorcycle shop and bought some different main jets. I figured that since the stock jet is a 130 that I would buy a 135, 140 & 145. After taking off my whole carb and replacing the float bowl screws with stainless ones I replaced the main jet and used the 145. The stock main jet is a lot shorter than the replacement jets I bought. Would this be a problem? After priming the carb the bike started right up. Here's where I need your help. PLEASE!!!! The quad idles great but doesn't run all that great either. The throttle response is very flat. It will rev but not as quick as stock. It doesn't backfire. About 3/4 throttle is the worse and it doesn't seem to have much snap. I pulled the plug and the tip was white, while the start of the threads is black soot. I'm running lean right? What do I do? Different jet, different mixture????? HOW DO I ADJUST???? Any help would be greatly appreciated. Thanks.

 

[kook]

Compare the performance cold to the performance when warmed/hot - how does it differ?

 

[suzukaholic]

I HAVE BASICALLY THE SAME SET UP AS YOU DO.. INSTEAD OF THE K&N SET UP, I HAVE THE UNI... SAME THING IN AIR VOLUME !!! I AM AT SEA LEVEL AND RUN A 152.5 MAIN JET.. I RACE HARE SCRAMBLES AND IT SMOKES EVERY OTHER BIKE OUT ON THE TRACK.. YOU ARE WAY TO LEAN.. UNLES YOU ARE AT A VERY HIGH ELEVATION.. BUT IT SOUNDS LIKE YOU ARE TO LEAN BECOUSE THE TIP OF THE SPARKER SHOULD NOT BE WHITE... ONLY A NICE TAN COLOR... AND DON'T WORRY ABOUT THE THREDS.... AND WHAT THEY LOOK LIKE... JUST THE SPARKER.... K.... PEACE OUT !!!

 

[Zero Z400]

Is it cutting out at 3/4 throttle? If it is, then ur to rich. Also make sure when ur doing jetting test that the bike is compl,etel y warmed up and then take it for a ride. After 10min stop and look at the spark plug, and then ull kno what to do.


Later

 

[RyanZ-400]

Thanks guys for your help!!! From the looks of the plug I'm running way too lean. I'm using the 145 main and I'm letting it get plenty warm before riding it. The plug end is white. Do I need to go to a bigger jet if it's running lean? Also, I never adjusted the needle, mixture screw, pilot, etc. when I put the new main jet in. I don't even know how to do the adjustments. Could that be the problem that I didn't mess with anything else? Do I need to make more adjustments. HELP!!!!!!

 

[spaguru]

See http://www.z400central.com/forums/viewtopi...p?p=13954#13954 for jetting guide...

 

[jlracing]

jets

That info is nicebut I don't see what to do if it's rich or lean.Also does anyone know what the measurement for the 3rd groove on the needle is.Mine looks different compared to a friends.And runs very bad. Spitting flames foot out the exhaust. :flamethrower

 

[Corpsie]

Re: jets

QUOTE

That info is nicebut I don't see what to do if it's rich or lean.[/b]

If it's rich go down a jet size.

If it's lean go up a jet size.

 

[Barely Legal]

Go up to a 152.5. That'll probably solve it. You've not getting any fuel in there. Plugs white and does not rev.

 

[bvstone]

Sounds like you got the wrong jet. Mikuni makes 3 types of main jets, small round, big round, and hex. The rounds can be interchanged but the hex have a totally different fuel measuring system. The hex jets are used more on TM/TMX carbs than the CV carb in the Z.

If your jet is a hex one, get it out ASAP and get the right kind of jet.