Thought you lads might like to see my latest modification. My bike is a YZ450, with a WR 5 speed motor, home tuned, its pretty quick now just a little slower than a 650 'Berg, and quicker than most 450's. My Akro pipe I had before was loud, kept blowing apart, needed re-packing..after numerous and loads of attempts to make it quiet, with success but didnt stay together, I decided to make my own pipe. As its supermoto I want more top end, so based on the fact that the 748's have 55mm headers, and when I raced a KTM550 supermono I built a 60mm pipe (two 38mm headers into a 60) this was the only way forward. Step forward my sponsor in road racing, and they made a selection of bends from 50mm stainless pipe, 0.8mm wall thickness with a 38mm to 50mm taper for the stub. I spent 8 hours hacksawing, tacking up, pondering, welding and viola, a new system for no cost ! Coupled with a straight through all titanium oval silncer, and a baffle in the end and its at 97db where the Akro was at 102db - yikes. Th esilencer is longer, bu I made it so it fits behind the number board neatly, and it doesnt stick out any farther than it used to, clears the tyre as well ! Mission accomplished ! Strangely, I gained 1hp throughout the rev range all over not just top end, but is a lot quieter. At the track, it feels smoother bottom end and just keeps pulling, not like before when it pulled from bottom and went a little weak on top. The dyno graph didnt read what it feels like on track - strange. Got my first top 10 in the Nationals last weekend, at a track I didnt like. This is only my second season, and 8th supermoto race meeting, so am well made up !