Ok so i did a little work yesterday to.
It is an inexpensive way to tune the engine for som extra horsepowers

people that did this mod are very positively surprised

maximum speed was 20km/h more and another guy said his bike wanted to wheelie at 4500 rpm instead of 6000 rpm. And it is a very easy mod that anyone can do

total kost of this mod was 25 Usd
Start with taking the carborators of the engine and put it on a bench or if you dont want to take it completely just put a wood board on the frame and work on there
Okej first step i started by opening up the end where you can pull out the throttle needles
When you open it up it would look like this
Pull the throttle out and then pull out the neddle holder
This one.. just pull it right out
Then you can take out the needle but make sure you get the little washer out to.
then you have to have some M3 washers availible put two of those on the needle and then put back the original washer. so totally ther should be 3pcs but make sure the original one is the last one you put on.
And then put it in the throttle again and back with the needle holder and then put it toghter, and do the same to all the needles.
Then you have to change the main jets. I bought 140main jets instead of the original 115.
(The one to the left is the 115 and the right one is 140)
Turn the carborators around and open it up
Take out the original jet and put in the new bigger one
And then put it all together again.
Now you have to tighten the mix jet and when it´s maximum in you turn it 3 1/2 turns back out again.
i marked it with a red arrow on the picture
Maybe you already new how to do this mod but if dont. DO IT

That was all for now guys.