Good Morning,

I have a Sunil I believe, either 110 or 90, and I am having trouble with it being boggy on the top end.

Here are some facts that I know and have done:
It idles fine and has good response up to about 1/2 or a tad below
It is a 5 wire cdi
fresh gas
Took carb apart, I can see daylight through all jets, float is not sunk, all looked fairly good
It blew the halogen headlight and the small 12v bulb
I fixed a few wires I think may have caused this, but not sure
I also unplugged the voltage reg and drove with it off and there was no difference in performance

It sounds as though there is a speed or rev limiter on it, it just gets to a certain spot on the throttle and it won't give you no more. You can push it wide open, and it just lunges and bucks a sucks hard bit but no backfire.

I have tried turning the little screw forward and backward with no increase in top end performance.

I'm not sure where to turn to next. Timing, Carb Jetting? Spark Plug? CDI? Voltage Regulator causing over voltage?

Also, these little things make some impressive AC voltage! It hurts to get shocked by them!

In looking at the back of the quad, I have a green LED Tail Light with 3 wires. Now it only comes on when brake is applied, is it supposed to illuminate as a tail light as well? I notice there are more LED's inside that do not illuminate when brake is applied. Also, at the back is a two little wires that are just cut off. What did these go to? I am pretty sure it was not the "horn" as it is located up front and is disconnected from the remote box. And the remote box has no fuse in it.

I have followed along fairly well to get the wiring figured out so it all starts and stops correctly, now it is just to get it to run correctly.

Thanks for any and all help.

 

Welcome to the forums.
I'd check the compression.
2 or 4 stroke?

 

it is a 4 stroke

I would think the compression would be fine since it starts so easy when hot or cold.

 

If the air filter isn't clogged and the plug isn't black then the air flow is probably good so look for fuel starvation but still change the spark plug and see what happens

 

I'm going to take the carb off and clean it one more time, ditch the fuel filter for a new one, and get a new plug and see if that helps any at all.

I pinched the fuel line off and took it off the barb on the carb and ran it out of gas. I put the back tires on a block so they could free spin and most of the time it was just as boggy, but for a few seconds, it actually responded very good.

I'll get it all cleaned up again and get back to you all.