I put a r77 yoshi slip on exhaust on my gsx650f, its stainless steel with carbon fibre tip finish. The difference is surprising, the bike sounds heaps better, it feels like the hand brake has been released and zips along ,the bike feels slightly lighter as well and looks cool.The pipe gurgles slightly when going down the gears. The yoshi company claim 5% increase in power, for $625 the pipe is worth it. :grin: pictured with exhaust. - you get the idea , this picture is from yoshi web site.