Fuel pumps were really never a problem. If you just want to premix,drain the oil tank,pull the small injector line from the pump to the carb and cap off the carb nipple. Premix 40/1 with a good synthetic.

 

Is there any potential that it could fix the compression issue, or do you think I got a crappy top end.

 

The niche top ends are a china top end with their stickers on them. They are all the same. 10-13 bucks each in volume on Alibaba.
After dealing with the china stuff, I think it's all junk, but it is affordable.
If you used the niche studs, this could be the problem. The studs are especially junk. I think they stretch.

 

As long as oem cylinders are 140 bucks by themselves people are gonna go gaga when they see those 35 buck kits. Really can't blame em as I'd probably give one a try myself just to see. 50/50 crap shoot on cheap Chinese electrical modules and engine top end kits as to getting one to work right,but the pics look so pretty..

 

made some progress. runs great at idle but bogs when giving it throttle same as before, but when i put the coke at 1/3 it runs pretty good. Is there a carb adjustment I can do?.

 

According to the manual the choke is on when lever is to the right (see below) is this correct. When I start the ATV i have to have it all the way to the Left, then move it to the right when ATV is warmed up (idles fine)...When lever is all the way to the right it runs like crap, but when all the way to the left runs good if throttle is applied. Have i had it backwards the whole time, if so do i just adjust the air screw?


All Youth ATVs are fitted with a manual choke system.
Apply the choke by moving the lever to the right.
Release the lever to verify the choke slides freely when
applied.

 

Yes you've got it backwards. Fully left is choke off. IF when warm it bogs off idle unless you have to move the choke right a little,then either you have trash in the carb stopping up the jets or the jets are too small. Can't remember if you mentioned whether this is the oem Mikuni carb or one of those Chinese knock off carbs that may not have the same jetting or that a lot of people found trash and junk in them from the factory and had to clean up before they would run right. The small air screw at the back of the carb should be between 1 to 1.5 turns out from a lightly seated position. Around a #80 main jet,25 pilot jet if you have the oem carb. You have to be able to see light through both jets plus blow out all passage ways.

 

not sure if its stock or Chinese....i will play with the mixture screw tomorrow....i cleaned the carb and it looked really good...