Hi All, I'm 'gearing up' to build my first gas powered bike. I have been reading posts and threads on the forum for several weeks now; it's informative and also a little overwhelming. I will be riding this bike about 20 miles a day to and from work, and will need it for 3 to 5 years. It's very important that I build something both reliable and durable. I really need to order my components within about a week, so it's decision making time. I'd like to get your input on the following questions to help me narrow down the field. I will be buying a new bike, probably this Motobecane Jubilee Deluxe. Save up to 60% off new Motobecane Jubilee Deluxe Comfort Bikes from bikesdirect.com If it's a bad choice, let me know now. 1: 2 cycle or 4 cycle engine? I know it's less expensive to begin with a 2 cycle engine, but I have to view this long term. In the engine descriptions on Supply Bicycle Engine Kit, Motorized Bicycle, Bicycle Motor, Motor Bikes, Moped. it states that the expected life of a 2 cycle engine is 1 - 2 years, and also says the expected life of a 4 cycle is 4 - 6 years. Is this correct? At 125 miles a week X 32 weeks = 4000 miles a year - how long do you think a well maintained bike can last with either motor? 2: Brand and Quality of Engine? I know there are dozens of manufacturer's in China producing very similar looking engines. But similar looking does not equate to similar quality. I've read the entire thread on Find a Dealer and Review, and many, many more. Often, especially on sites like ebay, you can't even tell who the manufacturer is, let alone what quality the parts are going to be. I've also read about new stock made with flimsy bolts, weak chains, cheap bearings, etc. I need to build a bike with the least potential for failure. Please tell me what brand engine you believe is best, if it is 2 cycle or 4 cycle. What are the best type of bearings and what brands use the good ones? Can someone please explain the difference between a dry friction clutch and a centrifugal clutch --- and which type I want for reliability and durability? From what I have read I am leaning toward a Grubee engine, but I need verification or education to what is better. 3: Size of Engine? When I have called some of the sponsors about engines I may purchase they mostly tell me that the external size of the 49cc engines are almost identical to the 66cc engines. This is important because Illinois technically restricts engines to a maximum of 1 HP. All of the engines I see produce more than 1 HP. But we do have some steep hills here in the river valley. So if the 49cc and 66cc engines look the same, I prefer the higher power. Mostly the police want you to obey the state bike speed limit of 20 mph. Do the two sizes look the same or way different? I cannot afford trouble with the law. Also - do the 4 cycle engines look larger or about the same as the 2 cycle engines? 4: Are there specific aftermarket parts I need to invest in no matter what motor I choose? If no motor kit is adaquate by itself, tell me what aftermarket part I want to beef up from your supplier. I would love a kit to be complete and all well built, but if that's just not the case, please tell me where to strengthen it for higher reliability and durability. I really appreciate the time you spend helping me work this out!