Hey Samy, I thought I'd offer 3 other things to think about since you say you are new:
1) It might be a good idea to try out your engine for awhile before you start thinking about mods and trying to break the sound barrier. Remember, the bike you put your motor on will STILL only be a bike (bike tires, bike brakes, etc.,) only it will be heavier. You may not think 30mph is fast until you are cruising with traffic and you find yourself rear-ending a car in front of you 'cause you can't stop short enough, or rolling off the road shoulder because you cannot corner as tight. Motor-bicycles are fun and economical but can be dangerous too. BELIEVE me, if you're just wearing a bicycle helmet, at 30mph the wind will be so loud in your ears you may not be able to even hear your engine!
2) Check your state laws also on SPEED restrictions for motorized bikes. In my state the max limit is 25mph (though amidst other traffic I am too small a target for police radar). But, if you're cruising at 40mph a cop can nab you just on "visual estimate" and write you a "speed too fast for conditions" ticket rather than for a particular speed. With your past driving record a citation sounds like the last thing you would need.
3) Also (lastly) you may wish to check closely with not only state laws but also any city ordinances of places you will be riding through. Though you might not need a motorcycle endorsement on your license you may still need a valid, active drivers license to ride your motor-retrofitted bike like my state does. If you need one you might be ARRESTED after being stopped for your Mach 5 speed....
Just a couple things to think about.