adding homemade "powerbomb" or "megamomb" FS 650

Hi !

I am running my FS 650 on the track from time to time.
And today the tracks are getting stricter ans stricter about sound

We have a 95dB pass through check at the tracks
Last year I was just on 94/95 bD bepending on the weather etc.

Have replaced my modified stock muffler with a bigger oval accra with modified outlet.
Have also fitted the bike with a more wuiet air-filter and added sound absorbing heatshild arround the airfilter/inside tank.

to get the soundlevel down even further to be on teh safe side now when the trackdays are running up I have 2 things running arround in my head.

1.
Would a parallel pipe take up any sound, like a powerbomb or a megabomb ?
and how do a accra powerbomb look like on the inside
2.
Maybe I shoud try making a Y-pipe and fit 2 modified stock mufflers as twin-system at the back to get more damping ?
but still realy feel that the most sound is coming from the intake/airfilter.

canolman said:

Hi P
95db!
We are 105db here and I find that tough! I run twin silencers, 2 into 1 into 2, don't think I could run one end can without baffles which steal horsepower. With a stationary noise test quite a lot of noise comes from induction so if you can enclose the filter without restricting it too much it might help. Single cylinders are tested here at 5500 rpm. I'm working on a pair of reverse cone end caps to fit in the end of straight through race cans to knock the decibels back and speed the exhaust gas out at high revs. Have you tried wrapping the pipe? Might not be practical if you ever take your bike off road but does help. Noise levels are going to be a big problem in the future!!

Click to expand...

yepp 95dB !!
not on standstill, but on driveby.
BIG problem, and authorities, birdlovers etc want to lower it ever moore
Not easy for the track-owners


Have wrapped most of the pipe
Any pics on how you run now and your plans ?