| Author | Message | ||
     Torco406 |
I have a D & D Exhaust on my 2003 XB9S and is louder than I would like. Does anyone make some kind of insert to quiet it down a bit ? | ||
| Torco406 |
I see in the exhaust shootout that the Jardine makes more power than the D&D system on the XB9. Does anyone know what kind of power the Jardine pipe makes with the QMI insert? I am looking for an exhaust system that looks good, provides good power and has a reasonable volume. The D & D is just a little to loud for my taste. | ||
| Jbolt |
I have a D&D also and was thinking the same thing. I read somewhere about making your own. This is what I found just haven't tried it yet. Make a tunable baffle by purchasing a 1/4"x1" thumb screw or taking a 3/4" outside diameter washer and weld it to the top of a 3/4" x 1/4" bolt. Now Drill a 1/4" hole about 1" from the end of the drag pipes. Take the tunable baffle and place a 1/4" nut and a lock washer (away from the large washer) the on it. Now insert your tunable baffle into the exhaust pipe like the example below. If you don't have access to welding equipment, try this handy little trick sent to me by Nick What was used was 1/4" x 1" thumb screws which can readily purchased at any local hardware store for about $ 0.50 a piece. They work great. The "football" shaped head on the screws measure approximately 3/4" x 1/2" so they have about the same surface area as the 3/4" o.d. washer because of the lack of the hole. And they do not require any fabrication. It is amazing what a little creative thinking can come up with. You can tune the baffle by changing the angle of the thumb screw or washer to the exhaust pipe. For maximum torque, the washer will be at 90 degree angle to the pipe. For maximum horsepower the washer will be parallel to the pipe. How well does this work? Bike Tech received a dyno run sheet from Gene P. that just showed what happened by changing the angle of the thumb screw. Three runs were done. Thumb screw parallel to the pipe (run 7), 45 degrees to pipe (run 6) and 90 degrees (run 5) to the pipe. Judge the results for yourself. This also shows you the benefits of dyno tuning something as simple as your exhaust system. Run 7 (open or parallel to the pipe) Makes the most power, but has a huge hole in the power band just above 3000 RPMs While run 5 makes the lowest horsepower (approximately 68), the 2500-4000 RPM power is the highest. This is the RPM band that most riders spend there time riding. Run 6 improves the 3000-4000 RPM horsepower drop over run 7 without any significant drop in maximum power. Where did this come from? This isn't some new technology that was just discovered. Any rider who remembers the Honda 250 and 305 Scramblers of the 70's should be quite familiar with the technology. In addition to tuning the power band, it also adjusted the amount of noise that came out the exhaust pipes. It was a well known trick when it was done by Honda. For those of you who are willing experiment more, the size of the washer can be increased as can the size of the hole in the washer. A strong spring can be used to hold the washer in place in relationship to the pipe and a "wing nut" arrangement can be used to adjust the angle of the washer. | ||
| Jbolt |
Yea sorry, I stole this from another forum. | ||
| Torco406 |
That is fantastic information , I will be experimenting with that. I was just thinking of making a solid insert like Jardine's QMI or supertrapp's "snuff r not" but this seem simpler and I like the tunable part. Thanks for the cool idea. |
