Yar hidalgo bro the tire ur using in ur chopper is a car's tire.. and its totally flat! im afraid that once ur bike is done it would not be good at cornering due to this flat tire... u need a round edge tire, beshak gari ka tire ho, woh bhi rounded walls mein mil jata hai..
And agar apne 4 stroke engine lagana hai, aur apko aik decent power wala engine chahye then i am afraid k apko 250cc tak ka mind bana parega! 200cc engine 4 stroke would have less then or equal to ur RX115 power.