The bike now will run all day long at mid 20's to lower 30's+. Well, there's a very long hill here in SW VA. that will give any vehicle a work out. I would really be doing good to top hill at around 10-13mph, with also some pedal power?!! Ok, I extended expansion chamber 3" longer on bike. Now, the bike will top this long monster at 21mph, and just continue on at normal posted speeds. (NOTE:It's not a full blown torque pipe like Jag offers plans to build on his site)..................but just adding length to my expansion chamber, really has done wonders!