Well a little background on the quad and I will let everyone come up with a theory that could possibly be wrong.

I bought the quad o about 3 months ago. When i went to see the quad it fired right up and ran fine. Took it home put it in the backyard until I got it registered (florida law). Well I live in a condo association and i have a fenced in backyard with no garage. The quad wouldnt fit in the backyard to i had to take out a section of fence to make it work.....no fun. Anyways thats the reason the 4 wheeler sat in the back yard for a bit.

Almost a month passes and I finally have it registered and find time to bring it out riding. Nearest places to ride is an hour away and i dont own a truck so i have to rely on friends. Well I go to fire up the quad and it has a hard time starting....I figure well its been sitting for awhile once i get her warmed up it should be fine. I try to take it up the street and turn around and it dies. Still thinkin same issue. I load it up throw some gas it it and i take it to my forestry place to ride it. Same problem when I unload it but after an hour problem goes away and the quad runs perfect.

Now the quad sits for another 2 months. I decide to put a K&N Filer on it a K&N Lid and a CT Racing exhaust. Again I go to fire it up same problem but this time its smokin a little. So I take it to my local Suzuki shop to have them rejet it thinkin that should take care of it. They throw a new spark plug in rejet it and bring it out to me running.

I load it up and take it home drive it up the street....I go to turn around and it dies again. Then has a hard time starting. Now i can't get it started at all. I figured somehow I flooded it and I will let it sit over night. Well next day comes the thing still wont start. I pull the spark plug and check it out its dry. Its a new plug but it has some black marks from the 5 minutes of run time and all the crankin it had so I hit it with a wire brush. It finally cranks up this time and dies 4 seconds later. I try to crank again and now it sounds liek batteries dying.

I take some jumper cables to it and it fires up. I hold the gas on it for a good 3 minutes to let it warm up. It is finally idling. I let it idle for another 10 minutes and decided it soudns good to go. I take it up the street agau and guess what happens when i turn it around. DIES! and of course does not want to start again. So i give up....whats wrong with this thing!

I am driving home today in my car and the only thing I can come up with that might make sense is......bad gas? It had the hard time starting the one and only time i took it riding but i filled it up with a half take of new gas at the pump and after a bit of time it ran fine....Well after 2 months of sitting on the same tank of gas i figured that might be causing the problem....

Whats everyone think I am staring to get frustrated. I heard alot of good things about the Z400's and I would hate for this to be my first one leaving this bad taste in my mouth

 

I would take apart and clean the entire fuel system including flushing the tank and jets and lines......

I would also replace anything rubber or plastic that could be breaking down and feeing small bits of solid junk into the carb.

Your problem will be hard to find in person, and probably impossible to find via remote access over the Internet.

Being that it seems to happen when it warms, or when the ATV moves, it could be anything. It sounds like a fuel problem but it could also be something else...

 

Well maybe but the thign is an 05 how could stuff be deteriorating already.......im startin to think the suzuki guy just didnt jet it properly.....even tho the problem was there when it was stock....i dono anymore thats why im asking u guys...

 

Will it shut off when it is sitting still and you turn the bars? Maybe you have a bare wire rubbing on the frame.

 

<div class="FTQUOTE"><begin quote>Originally posted by: smokin.legacy

Well maybe but the thign is an 05 how could stuff be deteriorating already.......im startin to think the suzuki guy just didnt jet it properly.....even tho the problem was there when it was stock....i dono anymore thats why im asking u guys...</end quote></div>

Well anything is possible... I was probably grasping at straws with what I said. You're right it would be odd for an '05 to be showing deterioration but you never know. People do strange things to their machines. If someone put something into the fuel at some point it is possible that some breakdown of plastic or rubber could occur.

My basic point was since you don't know the entire history of the machine in exact detail, troubleshooting can be tough. So I was suggesting that you simply eliminate anything like dirt or blockage and go from there....

If you think it is a jetting issue, try blocking/opening the intake to see if you can determine where the fuel/air mixture is. Does it stall with the box lid on/off or can you duplicate the problem while the machine is sitting/moving ......

Bring it back to the dealer if you are still stumped and think they are at fault.

 

You might want to check your valve clearances while your at it!!

 

Check under the airbox lid for rats being in there. Also you could change the position of the petcock under the tank to see if it helps.

 

I'd vote for Bad gas. Sitting is bad for gas. It lets condinsation form an dnow you have water in your gas. Drain the tank and make sure to drain the bowl on the carb. I'd also ask what size jets were put in her.Mine needed to go from the stock 22.5 to a 25 pilot jet to get her to start and idle right. Go start with new gas and let us know what happened. If you let her sit for a whaile then add Stabil to the gas and fill her all the way to the top so theres no room for condinsation to form.

 

hey, i hav a 2007 ltz and i kind of have the same problem, when i turn to its full capacity , especially when warm, the quad turns off, i then found out that when turning suzuki had a design problem, the chocke cable would pull when u turn to full capacity, so i just extended it and problem was fixed [img]i/expressions/face-icon-small-happy.gif[/img]

i hope it helps!!

 

Gas starts breaking down after about 60 days. How long did it sit before you took possession of it? Who knows, right?

Do the easy stuff 1st. Clean the carb and replace fuel filter if it has one. Replace the gas and put some fuel stabilizer in there if you are going to leave it sitting for so long.

Stop doing mods to it before you get it running right! You might be just adding more problems to your already hard-to-diagnose problem.