i am still riding my first build i made during the summer. it has given me h e l l , but i have given it a good beating too. i have a gt5 with cns carb from gasbike, they had the lowest prices. first thing to go wrong was the head bolts pulled out of the engine and ruined the threads on the first long ride i took. must have been over tightened at the factory and the heat from a long ride weaked it enough to thread failure. so i tried to contact gasbike. near impossible. the # and email on the site doesn't pick up, you never talk to a live person. so i make a youtube vid explaining my problem and a guy responded that he had the same problem, and gave me the # for one of the guys at customer service. i called and they didn't pick up for a while but finally got to em, and i sent back the bottom end and piston cuz i couldn't get it off. so i got a new engine minus the head and cylinder! put it together, and i can't find the exhaust pipe! mom must have thrown it out cuz she thinks half my stuff is junk. so i do a little research and decide to get the sbp pipe. put it on, and now my bike runs lean to the point it barley runs. i try everything with the carb, but still too lean. my solution was to get small sewing needle and use the end with the loop as a drill bit. i chucked the main jet in my drill, and go at it. cleaned it up, and put it in the bike. runs just a little rich during warm weather now, but better than lean. in the winter now it runs perfect. well, tinkering me decides that because i'm out of money and my gas tank is near empty, i put some 20% nitromethane glow fuel in the tank, about an equal ratio to gas. it ran rough and idled up and down, and ran really weird i don't know how to describe. but it had tons of power so i kept running it. and it was backfiring at ton so it was jerking on the chain at low rpm. this eventually worked the chain tensioner loose and when i made a speed run past one of those radar things on the roadside, the fastest run ever at 35mph, it fell off and i lost it. then came a slew of bad "prototypes" for a chain tensioner because i don't have a credit car to order one and i was too impatient anyway. none worked well. so then just today i had the idea to move the engine forward using washers behind the mounting bracket block thing. it did the trick! so i tinkered with the carb to get it right, and i did. took it for a ride down some bumpy ally ways and got to a baseball field that is soaked and had very deep mud, so i thought it would be fun to ride in it. that is when the rear mounting bolts broke because i over tightened or something. the chain got caught in the front sprocket because the engine shifted position, and i had to drag the back tire all the way home 4 blocks away. just ordered new threaded rod and will pick it up tomorrow! and that is my motorbike story! hope you liked it.