I have a 01 wolverine that sputters after half throttle. I already checked the brake switch, rebuilt the carb, and new spark plug. It will fire up first time and idle great. If I go over half throttle is starts kinda sputters. I've noticed if I have the choke fully on I can rev as high as I want. But if the choke is off I can't rev engine over half. I feel like it's not getting enough fuel unless I have choke all the way on. Any ideas?

 

Make sure airbox and cover is on...without airbox it will be way to lean. If it is still leaning out the check fuel flow from gas tank, could be filter in tank is clogged, usually at the petcock. If you have good ful flow then you probably have a clog in the carb. Did you use a good rebuild kit with factory settings?

 

Kymco 450i I have good flow from the tank, I even drained old gas and filled with new then let more run out hose. I used a rebuild kit from motosport, it's the same place my buddy used with no problems. I had the kit installed by a ATV mechanic. I guess it's possible I sucked something immediately from the air box into a fresh carb. But why would it do fine if I had the choke wide open? It will rev great if it is but not if it's half or off.

 

First you stated you needed full choke to make it rev then in 2nd post you said it revs with choke wide open....cant do both!

 

Sorry I'm thinking full choke and wide open we're the same. The choke has to be all the way on for it to rev. If I turn the choke to half or all the way off it won't rev up. Does that make sense? I know very little about carbs. I was Just researching and they said I'm either getting to much air or the air is right and not enough fuel. I really don't know how to check.

 

That sounds better, no matter what your not gettin enough fuel! Check for weak spark, and color of your spark plug. Just wondering if some crud went thru the fuel line and caused a restriction in your rebuilt carb. Lots of folks rebuild carb first then clean fuel system...do the opposite and clean fuel system first then rebuild carb.

 

Thanks, I will try that tomorrow and let you know. I appreciate the help!

 

Well now I'm worse off than what I was. I installed new spark plug and cleaned carb real good. Took out jets, diaphragm, fuel/air screw. Cleaned and blew out everything. Now the damn thing won't even start!

 

Is the new plug wet? You need to determine whether to much or to little fuel. What color is the spark on the plug? Is the carb set to factory specs?

 

Yes the new plug was wet. Spark looks normal. I don't know the set up. Both jets (main and pilot) are turned all the way in and the fuel/air screw was 4 turns out. That's how it was set for my original problem. I took apart, cleaned, and put everything back in the way it was but now it won't start. I get a little bit of start (like it chugs 2-3 times on the first pull) then dies and won't start again.