Hi (second try at posting)
Just bought two 90 vipers for my daughters. One of the quads seems to hesitate a bit when I give it throttle. The other is nice a smooth with no hesitation. Both statrt and idle fine. I clipped the green wire on the cdi and it seemed to have helped a very little bit but still every now and then I'll give it gas a it seems to hesitate/die then it picks up fast. Any ideas would be greatly appreciated.

 

Im only guessing, but for a long time we had this with my girls Kasea 90 and thought it was just jetting at first, then found out that her choke was bad...

 

Sounds like possibly some type of fuel problem.Make sure your tank is full and the fuel lines are not kinked or plugged.There is also a small inline filter that may be plugged.If you remove the gas line at the carburetor and then turn on the gas at the petcock it should run out of the hose full blast.If all of this checks out you may have some dirt in the carburetor.Changing the spark plug wouldn't hurt either just to eliminate another possibility.Are these units new or used?A dirty air filter will affect your performance as well.The Vipers have manual chokes so that isn't likely the problem unless you've left it partially turned on.As an experiment when the unit hesitates maybe try giving it a little bit of choke to see if that helps.If it improves that would indicate a lean condition for sure.

 

hi
thanks for responding. To answer a few questions both these units are new and I used the same gas mixture in each (93 octane with 32/1 mix for first tankful). I did notice when it hesitated I did put the choke back on a bit and it ran better. I'm not real fimilar with mechanics. What do you mean by too lean a mixture? I did adjust the air intake screw on the front of the carb and it seems to be running better now. I turned it in about a 1/4 turn. I have a feeling it just needs an adjustment and hopefully that was it.

 

[quote]
Originally posted by: oldyeller
A .The Vipers have manual chokes so that isn't likely the problem unless you've left it partially turned on.
I thoughtthe Kasea and Eton were the same with the choke??? My ole man works on all the minis,Im still learning all the stuff on them, but I do remember that we kept messing with the jetting thinking it was off,she had a BAD hesitationso we replaced just abut all the could be replaced................Except the choke, after replacving that we rejetted to where we thought it should be and it was great!!! OldYeller is right on everything, could be sooo many small things.Checkers~~Im assuming you dont have a pipe yet....Correct????

 

Checkers thats quite a bit of oil in the tank along with the oil pump running.Thats probably part of your problem assuming the pump is working ok.After you get that tankful of gas burned out of it it will probably run much better.The adjustment you made on the carb may have corrected the problem as well.Watch the oil level in the tank to be sure its dropping.It won't move much in just one tank full but it should go down a little.You may foul a sparkplug or two burning that much oil.If the problem persists I would take it back to the dealer.If your playing around with the carburetor and something happens to the engine they may not honour your warranty.By a "lean mixture" I mean its not getting quite enough fuel as opposed to a rich mixture which is too much fuel.I think most of the mini manufacturer's are moving away from the automatic choke as it was causing to much trouble,either sticking on or not working at all.

 

hi
Thanks for all the info. I didn't get a chance to run them today but I'm hoping the carb adjustment did the trick. Like I said I bought two of these and set everything up the same. The manuel told me to run the first tank of gas with a mix. Oldyelller, considering what you said I would assume my machine was running too lean since when I had the hesitation problem and I put the choke back on it seemed to run better. Am I thinking right? I guess the adjustment I made increased the flow of gas to the carb? Also something else I noticed was the atv that was running fine seemed to smoke alot more than the other. After I made the adjustment the one with hesitation seemed to start smoking about the same as the other. I don't know if it just seemed that way or it was related to something I did.

 

Sounds right to me checkers.The smoke should settle down after you get all that oil burned out.Good luck with your new machines.[img]i/expressions/face-icon-small-smile.gif[/img]

 

Thanks for the help all.