People's pipe doesn't hang that low.
Here's the circuit pipe in action. Wait for the qt50 to come into the video. 41.5mph with stock carb, mlm circuit pipe and 1.5mm spacer on stock cylinder. Circuit pipe is only $130 something. Sell your stock exhaust and get a much better pipe for peanuts.
What's top speed on a stock qt - 30mph? 38% better with changes above. It does have pw50 gears as well.