Re: 2-stroke vs 4-stroke
if we are talking about kits 2 strokes vs kit 50cc 4 strokes, 4 strokes have about the same power, are bigger and more expensive, but much more reliable. the 2 strokes look better, too. i am still building my 99cc predator. the disadvantages are size, weight and price for the drive train, to be expected because it's not a kit. they are cheap to replace, only $100. tons of power and reliability. i have a 2 stroke 125 dirt bike and love it, i like the sound and power. super light, too. the only good 2 stroke for motor bikes is the morrini and similar engines that cost more than $400. i've never rode one but i like manual clutches so i will never buy one. i am thinking of using a 65cc dirt bike engine for my next build, they are super light 5 speed manual 14hp screamers. i will buy a bike and part it out, possibly getting the engine for free plus my labor. i calculated it will have a better power/weight ratio than a kawasaki ninja 250.
bottom line, it's personal preference. what kind of performance do you want? what is your budget? what skills do you have?
some people say that a motorbike defeats the purpose of a bike. i tell them to get a flintstone's car.