To drill or not to drill

I have read some of the archives and some people say it is a good thing to drill the exhaust and some say it doesnt do anything. (baffles) I already did the cap mod and like the sound. If I do it should I drill with what size bit should i use a hole saw and cut all the way down?? Thanks in advance

Kientech has some simple stuff for stock pipe, thinking about it myself. big prob on the S/SM is small headpipe dia.

Yeah - what do we have to do - I'm sure there isn't a power gain, but noise..

I'm up for it....How do you do it? What kind of drill bit?

bump bump

No power gain at all, but it does help a little with reducing excessive engine braking. And if you just drill the middle baffle, there's hardly any increase in noise, either.

See you say no power gains but,, second page, what immodrz you say no but these guys say yes...and I am sure that if i keep looking I will find more that say yes. I know someone is going to say just breakdown and buy the yosh full system. but I cant see myself spending that much money on a pipe, maybe if it was coated in gold or something. besides i am not looking to match the power gains with the yosh, just get some more out of the stock exhaust. Thanks again for the responses

Anyone who thinks that drilling the stock exhaust is going to give them any noticeable power gains, is just fooling themselves.

But if it makes them happy to believe it, that's fine too.

Drill away and be happy.


The restriction on the S is in the head pipe....that is why you won't see the performance gains you are will however change the tone of the exhaust and reduce engine braking slightly.

I personally am still running the stock exhaust on my E. I have installed one of the billet tips which gave the bike the sound I was looking for and may have crispened it up just a little, but no power gains to speak of. An after market system is on my list when I can justify it.... :thumbsup:

What about removing the baffles? I know that when I had my fun car Eclipse GSX when I put the 3 in exhaust it removed all of the lag in the turbo but also gave it a ton of power. If the header pipe is smaller (more restriction) that the Yosh kit (less restriction). Shouldn't it gain some flow by removing the baffles?

The middle baffle and the end cap are drilled on mine...

No increase in power, but slightly better engine braking characteristics, and a slightly less scooter-like sound.

what about cutting the end of the muffler off and removing ALL the baffles? not drilling them

Just keep in mind... your neighbors will not appreciate an obnoxiously loud exhaust. You will probably also grow tired of it after time.

I bought a new 06 s and went up inside the muffler with a long punch and removed the first [last] restrictor plate and punched a lot of holes in the plate behind that, then on the end cap I pressed out the center [peenky piece] and wow huge power increase, I recomend just taking a holes saw and drilling it out as large as you can, because I had to remove the screen to press out the end cap, then weld it back on. I also lost a lttle low end after that [to much flow] so I found a bairing race that fit perfect in the tip that choced it back down to 1 inch and got my low end back, This made me very happy and I'm very picky, I'm an A rider.

So use a 1 inch hole saw in the end cap and do the rest of what i said, you will not be disapointed and best of all it was free!!

As far as me getting tired of the exhaust you may be right. but I am going to call my dad now and have him send me his stocker since he has the yosh pipe. terry thanks for your help I will try to do it this weekend and see how it comes out and let everyone know. Thanks

So use a 1 inch hole saw in the end cap and do the rest of what i said, you will not be disapointed and best of all it was free!!

Duh...Sorry but where / what to run that hole saw thru?

(hold your smart answers)


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