I'm looking at trying to improve the flow in the exhaust of my 2000 XR250R, but on the cheap. The bike is only used offroad these days, and here's two options I'm currently looking at. Removing the tailpipe and rear muffler and: 1. making a new one up out of straigh pipe, so just free flowing pipe, no muffler to restrict nothing - wondering about noise but, would it be uncomfortably loud for me to ride maybe? 2. fitting the Laser Pro Duro 'Classic' muffler (http://www.laserexhausts.com/en/product_info/produro.html and http://www.laserexhausts.com/dotcon...nfo/bikes/produro/LASER_PRODURO_INOX_05_b.jpg) I have sitting here that we pulled off a Yamaha 600cc road bike (although the muffler is an offroad orientated muffler). Just wondering if there's any concerns regarding these? I'm probably going to have both made up anyways to give tehm a go. I've been told that bike exhausts have different theories behind them to that of cars (which I'm used to playing with). One thing I've been told is that prior to the mufflers on a bike the pipe is usually flanged or coned and that helps with the extraction or drawing of the gases or something.