I have a bone stock 04 Banshee and my buddy has a bone stock Yfz 450 and he kept on talking shit about how i should have bout a 4stroke and saying he would drag my ass on his 450 so we raced today and i outrun him so he wanted to go again becasue he claimed he missed second so i ended up out running him three times. So he called his friend who has a 450R the has a pipe, jets, slicks and has been lowered and I raced him and i busted his ass till fourth gear and he drove around me. Well me and a friend went back and adjusted my clutch and put the stock tires back on my bike and he took the baffles out of my stock pipes cause he said it would run better. When i raced the 450R the second time i outrun him so we raced about five more times and the same thing he could never run me back down is this normal?