like it said guys, list your mods that you have done that were free or so cheap it didnt matter... i think a lot of people want to know what they can do to the china girl to make it better without cash. or at least verry little cash. so list em what did you do that was free and helped out with power or gas milage or rpm or vibration or speed exe... so far i have ... 1- decked the head...i took mine down about 1mm a little more . this helpd with compression and gives you more low end grunt and midrange power, t also helps overall power everywhere. 1.1- polish the combustion chamber... this helps prevent carbon from building up and keeps your motor running clean 2- port and polish.. this is a tie for most important with adding compression... it helps flow more fuel air into the combustion chamber helping produce more power everywhere 2.1- grind 1mm off the roof of the exhaust port and 1mm off the bottom of the intake port... this helps correct port timing and will alow you to acheve higher reves and a more balanced powerfull motor. 2.3- deck 1mm off the jug face and add a 1mm or smaller aspacer to the case... for those who have acsess to a miller this can be free also, this mod further helps correct the port timing and depending on the spacers used at the case can raise comp also. for experts only!!! 3- port match your intake and exhaust to the jug as close as you can get them... this helps flow air fuel better and helps power everywhere. 4- extend your intake with an automotive hose so the carb is about 7-8 inches from the face of the piston... this helps with take off power low end grunt and a little midrange 5- TUNE YOUR CARB!!!! this will help EVERYTHING !!! your carb does not come tunned its up to you to do that, you may even need remove plugs covering adjustment screws and half to solder and drill your jets like i did but the results are well worth it ! you should always tune your motor wile its warm. 6- the exhaust, you can gut the stock cat muffler and make your motor flow more freely however this will make your bike a lil bit louder but for me gutting the exhaust and drilling a couple 1/4 holes in the cap made a humongus differance for me !! shure my bike is a little louder but it runs cooler, it rev's quicker, it pulls harder, and i can take hills way better than before!!! that is no placebo effect ether!!! the stock cat on my bike was sooo restricive i felt an imidiate change in low end power just by pulling out the cat, drilling 3-3/4 holes above the stinger helped top speed and midrange. 6.1 extend your exhaust by 6-8 inches to gain even more low end, need a welder and 3/4in pipe 6in long 7- the piston and wrist pin.... ok if your a good mechanic and are skilled or confident you can trim the piston skirt on the intake side. i trimmed 1/4 in off the entire intake side to help lighten the piston. 7.1 mark where your ports open to your piston with marker and grind ramps into the piston so the air fuel flowes smoothly over the ramps into the combustion chamber. i took it all the way and ground for all 4 ports in the shape of a 4 leaf clover pattern on my piston the exhaust and intake had large .8-1mm ramps and the transfers have .5mm ramps. this mod will lighten your piston some and help fuel flow into the chamber faster and more acuratly providing higher rev's and more power in your powerband. 7.2 drill out the center hole in your heavy stock wrist pin from 5mm to 7-8mm this will lighten up the wrist pin and help with vibration... if you have the money there is a titanium pin available but this is free mods. 8- spark plug... go get a nkgb5hs or champion L86C an iridium plug is best but this is free or cheap mods so ... 9-change your plug wire... you can use heavy gauge lamp wire or any 6mm copper wire. anything is better than the steel wire they give you !!! steel has 10 times the electrical resistace of copper. 10- fuel filter ... do not use the one they give you its junk ! uscrew it and buy a real paper one from anywhere mine was only 5$ from ace hardware ! my stock one clogged to easily and was tossed. the mesh filters do not block small particals anyway paper blocks the small particulates better. 11- run full synthetic oil 32:1 to 40:1 for break in and the life of the motor, for amsoil or opti 2 you can go even leaner on the oil richer on the gas some pics... plug before and after mods . you can see the 3 prong plug was the stock motor running with the carb set the way they wanted useing 16:1 mix like the directions say lol its terrable !!! the champion plug is after the mods running 40:1 93oct. broke the motor in at 40:1 93 oct also no point in running a differant oil at a diff ratio than i plan on using for its ife right ?