i have an ATV that is somewhat unique in the atv world, in that only these quadrunners, and the bigger brother, the King Quad, are set up the same... they are a smaller ATV, but have 3 range selections, (i.e. high, low, and super low) while also having 2wd, 4wd, and a selectable front locker... so for tight trails, and mountain terrain, they're the perfect all around rig... being a single cylinder, 250 CC rig, and weighing around 500# makes them nimble and fuel efficient... I even modified a set of aftermarket wheels to fit mine, in order to give it a more standard rear tire size, however, the carburetor is difficult to work on, and does not like elevation or temperature changes... The CDI unit failed on mine, and an O.E. unit was $300.00... so i converted mine to an older ford duraspark ignition control unit... which allowed me to run an automotive coil and spark plug... thus far it starts great, but can still be finicky to keep it running, and as it gets hot, it quickly looses power... since i'm rarely one to let sleeping dog's lie, if you will, i started looking in to some of the fuel injection units, and quickly found this forum/page... i am an admin for a facebook community specifically for these rigs, as many of our members tend to snag every rig they can find... it would be a huge advance to add Fuel injection to these ATV's, so i look forward to seeing what you come up with and how everything works out.