We just passed break in for our raider kart and installed the Hop up kit! What a difference! We have a killer track on our ranch where we built jumps and berms. Right now we do time trilas to see who can faster between my son and I. We are going to buy another Raider for some side by side action! Check back and I will post a link to some video we shot.
After break in, which I did in a hurry, my Raider single seat did an honest 41mph, basically out of the box. This was done on pavement. My cousin's double seat only went 37mph after break-in, but that all changed once we both put in the performance kit. Now I have a vehicle that will do 54mph on flat pavement if you give it a mile to run.