muffler+drill=??

GoldenMotor.com

Z00mz00m

New Member
Jul 30, 2009
6
0
0
Petersburg,West va
ok so i got an engine kit,installed it, and it seemed sick...witch in my eyes was normal because im 250 pounds...but i lost the cap off the end of the muffler what all xactly fell out is unknow to me...but i took a drill bit about 2 sizes smaller than a 1/4" drill bit...i drill 2 holes in the round peice,with the bolt welded on, that if i am correct is the catalac-coverter??i drill these 2 holes and got a big improvement in the stock muffler....but remeber i dont have thebottom cover on the muffler..and the bit size is 2 shades smaller than 1/4" .shft.
 

bairdco

a guy who makes cool bikes
Aug 18, 2009
6,537
264
63
living the dream in southern california
i kinda did the same thing, but i don't have pics, either.

if you take the screw out of the bottom, the cap pulls out with a pipe welded to it. i drilled 5 or six little holes thru the pipe, so it looks like a flute i also drilled a few 1/4 holes in the end cap. installed it all back together, and used a pair of vice grips to tighten up the bottom screw.

it's actually QUIETER than stock, and it got rid of some of that ting ting tinny sound.

seems faster, too.
 

Venice Motor Bikes

Custom Builder / Dealer/Los Angeles
Mar 20, 2008
7,266
1,797
113
Los Angeles, CA.
With the Raw kits, you can just remove the exaust pipe end cap, & saw off the inside of the stinger tube & put it back on!! (still quiet, & lots of power!!!) (^)
 

outlier

New Member
Sep 13, 2009
5
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0
Utah
I drilled a 1/4 inch hole in the end of the tube that has the bolt welded to it. pretty happy with the results: Good: top end increased significantly, higher revs and more speed, pulls hills a lot easier and faster. Bad: seem to have lost the bottom end... gutless on take off. I'd rather go faster once I'm going, so I'm fine with it.
 

BarelyAWake

New Member
Jul 21, 2009
7,194
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Maine
I respect that it's an easy and cheap (read "free" lol) modification, I even did it myself heh, but TBH it is just a work-around, yer not really "gaining" any power - yer just allowing the engine to breath a little better, allowing it to use the power it does have.

That's fine of course - but if you really want yer motor to not only run better but to get an actual gain in performance above stock - try the expansion chamber from Sick Bike Parts: Sick Bike Parts expansion chamber kit

Granted - it's not free lol, but it's worth every penny ;)
 
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Cogswelln

New Member
Dec 6, 2009
207
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0
Maine
Looking at the posts i think im going to drill into my already existing muffler. I am new to the motorized bike world having just built my first one with and 80cc 2 stroke on a Roadmaster mt bike. The thing goes through trails like a dream. I was wondering if there are any other ways to modify the muffler to make more use out of the motor?