View Single Post
Old 06-09-2008, 12:07 PM
Pablo's Avatar
Pablo Pablo is offline
Master Bike Builder & Forum Sponsor
Join Date: Dec 2007
Location: Duvall, WA PNW
Posts: 3,649
Default Quiet Needed!! Loud expansion chamber PIPE

You guys probably saw this post coming 5 miles out....or rather you heard me coming :bike:

I installed a Pocket Bike expansion chamber this weekend.

I'm done gushing about my new power (it's still amazing), now the reality of the new expansion chamber is setting in……this sucker is LOUD. I wouldn't mind if I lived in the country - but I'm afraid the neighbors will start griping. Sorta .226 machine gun fire - crack-crack-crack - slow idle is nice though. (Added beni, it even idles better than originally, surprisingly I had to back the idle screw off quite a bit) When idling it is not on the pipe - just flowing through, so to speak.

The source of this exhaust noise appears to be twofold. Per my ear nearby, part of it is my fittings up front - they are fairly loose. I can easily take it apart. Maybe expand the male half to make snug slip fit, on the male (steel) manifold I can use some exhaust system sealant goop, because that stubby steel flanged nipple could be tough.

The other is the so called silencer (it should be called a loudener) - it's not removable (welded to the pipe after the chamber itself). The silencer "cover" is riveted in place. To improve this one could be interesting. Drill out the rivets and stuff it? (I think it's empty inside). OR cut it off and attach an new quiet one?? Where is a silencer source? What will be left to clamp onto will be about 1" of or so 5/8"-7/8" OD stub. (I need to measure it)

I guess I'm open to any ideas as well as help finding a new silencer.


Reply With Quote