Re: MOAR POWER RAWRRRRR (questions)
I'm not understanding you. If you are uneasy @30mph, why do you want "more power"?
Don't remove the muffler end cap. The performance increase will be negligible and you won't be doing your neighbors or the hobby any favors by riding an annoyingly loud bike. Those who advocate removing the end cap and claim big power gains are only fooling themselves. It sounds faster, so it must be faster. Not true!
You might want to explore a smaller rear sprocket if a higher top speed is what you're looking for. Also tune the carburetor by experimenting with jet sizes. The expansion chamber exhaust is another area where you can gain some power.
Age and Treachery Will Always Triumph
Over Youth and Skill & "Charlie Don't Ride"