My exhaust mod

[Un-Caged]

After reading about the stock can mod where the rear cover is removed and the muffler end drilled, I decided to try a slightly different approach. Instead, I removed the can and drilled 9 holes in the forward baffle plate in line with the rear exhaust pipe. There are eight 7/16" holes surrounding a 1/2" center hole. I'm happy with the outcome; a nice throaty sound to the exhaust across the whole rpm range with no popping. Idle is only slightly louder and cruise rpm is between stock and slip-ons sound. If you want a little more sound without having to cut loose the end cap screws, give it a try.

 

[Warputer]

Good idea ....so basicly U drilled the opposite end from what everyone else has done ? No modification to the back end ?

 

[Un-Caged]

(Warputer @ Jan. 07 2007,14:54) Good idea ....so basicly U drilled the opposite end from what everyone else has done ? No modification to the back end ?

Exactly

 

[rockadaous]

hmmmm. i wonder how different it sounds.

 

[Schism]

i am curious about the sound myself because when i drilled my 9 holes in the rear, i also cut about a 1/2 inch. off the center pipe. would that cut be different in sound from your midpipe mod.? can you post a sound clip?

 

[Over_Easy]

curious what the diferences are between this one and the one at the rear of the can...other than being a lot easier.

 

[Un-Caged]

(Over_Easy @ Jan. 07 2007,19:36)

curious what the diferences are between this one and the one at the rear of the can...other than being a lot easier.

Not sure there, I haven't heard one done the other way. I'll have to compare to Jason's if we meet up again for Thunder Beach. I would guess though that the rear holes will be a little deeper sounding since the sound escapes directly instead of travelling down the tail pipe.
My mod is very mild sounding but definitely noticeable. I rode over to my friend's house after finishing, and the first thing he said was, "did you do something to your exhaust? It sounds better."

I'll try to catch a sound file tomorrow and add it.

 

[Deadeye]

Hi ... I was just about to go and do the original rear mod but I will wait for the sound file if you can post it. Anyone got a sound file on the stock sound and then after the rear mod? Gotta ask ... thanks in advance!!!

 

[WuzzaCBXRider]

I'm going to have to do both. Drilled the fronts on a spare set of pipes and can't hear any difference except at idle and then only barely. There does seem to be a deeper intake roar but no perceptable (loudness) from the pipes. Funny thing though, now my fast idle lever is either off or on, no middle ground at all. I'll remove the rear plate and drill there to see if the sound deepens enough to suit me. Wonder if a K&N will be needed to match the pipes once the front and rear baffle plates are drilled?

 

[Hy_Rolr]

Hmmm...veddy intaresting

 

[Un-Caged]

(CBXRider @ Jan. 15 2007,22:14) I'm going to have to do both.  Drilled the fronts on a spare set of pipes and can't hear any difference except at idle and then only barely.  There does seem to be a deeper intake roar but no perceptable (loudness) from the pipes.  Funny thing though, now my fast idle lever is either off or on, no middle ground at all.  I'll remove the rear plate and drill there to see if the sound deepens enough to suit me.  Wonder if a K&N will be needed to match the pipes once the front and rear baffle plates are drilled?

That's odd. Mine had no effect on fast idle and made it a little louder all around, but I do mean little. No effect to intake sound either. I still bet rear holes are louder though. I'll try to get a sound clip today.

 

[guido4512]

Very nice and cheap mod!

I took it a few steps further

by gutting the entire can and fabbing up some homemade baffles out of exhaust tubing. A little welding and voila! sweet sound.

Very cheap.

 

[dadofthree]

 

[fsusux]

(Un-Caged @ Jan. 07 2007,23:18) I'll have to compare to Jason's if we meet up again for Thunder Beach. I would guess though that the rear holes will be a little deeper sounding since the sound escapes directly instead of travelling down the tail pipe.

Rick,
I've enlarged the holes on mine since you heard them. (now running (6) 5/8th holes on each plus cut 1 1/4 off the tailpipe) Just guessing that it added about 20 more dB's (on the throttle, idle's not much louder) over what you remember hearing.

 

[Un-Caged]

Well here's the sound clip. If you're looking for a big boost in sound, don't bother. But, if you like your stock setup but would like just a little more attitude, try it.

Jason, I'll check the difference next time we get together.

null

 

[Over_Easy]

Sounds slightly more spirited, just no deep notes. I'm, assuming because the rear port is still the same it mutes the holes drilled at the intake of the can.

I believe the original method of drilling wholes at the exit of the can will give the deeper notes people may be looking for.

?: I have a dremmel for cutting the soft-weld bolts but will they be alright by simply tighetning them back in w/out welding?

Other option may be to simply cut at the mid-pipes until I get a full exhaust. What tool(s) would be recommended for cutting mid-pipes?

 

[fsusux]

(Over_Easy @ Jan. 16 2007,13:31) ?:  I have a dremmel for cutting the soft-weld bolts but will they be alright by simply tighetning them back in w/out welding?

Other option may be to simply cut at the mid-pipes until I get a full exhaust.  What tool(s) would be recommended for cutting mid-pipes?

Just use some Loc-tite on them for insurance.

Definitely try the can mod before you cut your mids. You may be happy with that until you get a full system.

I've got 6 five/eighths holes in each can plus the tail pipes have been trimmed. Really nice non-obnoxious sound.

 

[hayabusa99b/w]

very nice!!

 

[WuzzaCBXRider]

I won't get to really test ride the (new) pipes until this weekend but in my garage they sound great! Low rumble at idle and the rumble stays there when revving it. Not at all obnoxious but very deep and mellow.

What I did was drill the front end baffle plate with five 1/2" holes each and then after removing the rear end caps, drilled nine 1/2" holes in the rear baffle plate, three each between the screw posts. Masked and painted the ends with 1500 degree paint and reinstalled the screws. Doesn't look bad at all. Tried it with the end caps on and the sound was a bit more muffled but not very much. On my test ride I'll take the end caps for a comparison but I think I'll prefer the deeper rumble.

If it doesn't backfire or reduce the power, this is really a great exhaust mod with very little labor or $$$ involved.

 

[djorgensen3]

I have done both the front and rear of the stock muffler. If I can I will try to make a sound bite for you. On the rear of mine, I cut out the rear plate except for the cap mounts and then reached in with a long sawzall blade and cut the pipe off. I will try to get a pic of the inside tomorrow as well. With both the front and rear modified it has a very healthy and deep sound. It might even be too loud for me. I haven't had time to get used to it but with the helmet on and cruising it is loud. I can't say there is any power increase because with this cool weather these bikes scream even more. Anyway if I can figure out how to post a video I will do so tomorrow. Any helpful tips will be welcome.