exhaust question

[Griz53_imp]

while working on my cb1100 today I noticed 3 screws that attached a outer"cone" to the muffler..... I was hoping that taking it off would reveal baffles that could be removed for a deeper sound BUT it was just a steel plate...... now Im wondering IF drilling holes would "open" up the exhaust a bit to achieve the desired deeper sound ??? Has anyone tried this ? Results ?? yes, I guess im just a old school guy wanting more sound LOL pic attached so u can see what Im speaking off

 

[michael1954]

while working on my cb1100 today I noticed 3 screws that attached a outer"cone" to the muffler..... I was hoping that taking it off would reveal baffles that could be removed for a deeper sound BUT it was just a steel plate...... now Im wondering IF drilling holes would "open" up the exhaust a bit to achieve the desired deeper sound ??? Has anyone tried this ? Results ?? yes, I guess im just a old school guy wanting more sound LOL pic attached so u can see what Im speaking off

I did it to my Suzuki VS1400 years ago, and it sounded a lot better. Not loud, but at least you could hear it, and on this V-twin, it changed nothing in the way of tuning or back firing.

 

[Lord Popgun]

Been done by a number of members. Here is one thread with a pic in the first post: http://cb1100forum.com/forum/showthread.php?tid=8481

 

[PowerDubs_imp]

I did the same on my old FZR600 before I bought a proper exhaust for it. Sounded much better.

 

[SportsterDoc]

A 8" long 1/2" drill bit worked well on both Sportsters and first Bonneville, however, after drilling 4 holes (1/2") under the CB1100 muffler cover, I liked the sound at idle, but not accelerating or cruising; so the holes were covered with plates, attached by screws (drilled and tapped) to return to stock. So, if drilling is decided, you may want to figure out how to return to stock, if sound is not as desired.

 

[ymtnpoah11_imp]

Funny you should ask. I was reading the 'stock exhaust mod' thread this morning. (and it's corresponding poll)

While I understand the camp that prefers quiet bikes, I would ask - can you be too quiet? As a pedestrian and cyclist (who's been hit) I happen to think the silence of EVs are #&%! hazardous.

I didn't want to alter my OE pipe, so I never tried it. But... now that my bike has been down and the muffler rashed, I went for it today. The change is as-described in the thread, slightly lower, subtle and nice. I'm happy with it.

 

[Mixagon_imp]

I tried drilling on a Yamaha xjr and it just didn't sound right, it sounded more like the collector box was blowing. Good thing that I tried it on a used exhaust I bought cheap from the breakers.
Could you not buy one second hand to play about with and keep yours stock to put back on in the future.

 

[Charlie Bravo_imp]

It didn't do squat on my '13, and I drilled so many 1/2" holes there is almost no plate left. I've modded other bikes in a similar fashion with good results, but not this time.

 

[Maturecheese_imp]

Would drilling the rear plate to alter the 'sound' affect the fuel/emissions?

 

[Wagonpeddler_imp]

I remember years ago while waiting for my bike's PA state inspection....a guy brought in a bike with the exhaust tips drilled out. The mechanic wouldn't pass it because of that.

 

[peterbaron]

I failed every vehicle, including motorcycle that did not pass DOT/Canada.

"Reject if: muffler perforated"

 

[ymtnpoah11_imp]

The system will adjust for the new 'leaks.' Any emissions difference is likely negligible.

Inspections should be fine* The bike is (still) clean and quiet after the mod. Where would an inspection involve removing the cap?

In any case, it's easily reversible.