Free 5 minute exhaust mod

[moorenycc]

FZ6R exhaust mod video

Here is a link to a video I made of modifying the exhaust and also the new sound of the bike.


[ame=http://www.youtube.com/watch?v=IoNH7nouYiI]YouTube - Easy 5 minute FZ6R Exhaust Mod[/ame]

 

[Spunky99]

I used the exact same screwdriver set...LOL...

Now to make use of those 1/2" socket extension tools.

 

[Marthy]

What size of hammer were you using? Sorry mate, that's a quick and cheap mod but I can't see myself working on a bike with a hammer. When it comes to performance, there's more to it than just the noise.

 

[2w05thletes]

I believe this modification was for sound only and not performance at all. It's for the guys that want a louder bike and can't or won't afford the available aftermarket exhaust systems available at this time. Personally I want mine louder for safety reasons.

Thanks moorenycc for the video we requested. Much obliged.

 

[dannymac702]

What size of hammer were you using? Sorry mate, that's a quick and cheap mod but I can't see myself working on a bike with a hammer. When it comes to performance, there's more to it than just the noise.

The way I see it, this mod isn't about performance but just to increase volume somewhat which I believe is a good idea. The stock system is just too quiet. (My dog doesn't even hear me when I pull up to the house) Want to be heard but not annoying. May try this mod but agree that a hammer is way too redneck for me. Will drill it out if anything.

 

[dannymac702]

I believe this modification was for sound only and not performance at all. It's for the guys that want a louder bike and can't or won't afford the available aftermarket exhaust systems available at this time. Personally I want mine louder for safety reasons.

Thanks moorenycc for the video we requested. Much obliged.

SOUNDS like a couple of drill bits SOUNDS more affordable for more SOUND than an after market set of pipes SOUND. I agree on the safety aspect. Just SOUNDING off.

 

[Stephenfz6r]

Hi everyone,for what it is worth I am a licensed mechanic, this mod at the very least will reduce some back pressure, which will have an effect on low and medium range power response. The FZ6R exhaust is an integral component as to why the engine makes a linear line on the power curve. Normally the fuel flow via the fuel injection and valve timing would need to be altered to make up what would be lost with the reduced back pressure. Making more noise and loosing a bit of power is what you will gain. Is it really worth it? Depends on what you really want. Not attracting attention is the way I'd go.

 

[moorenycc]

when I did this mod I used a small sized hammer. You don't need a huge hammer or much force to punch through. I personally believe that there is not enough change in back pressure to cause fuel delivery problems. There is definitely more exhaust air flow now, but no popping, back firing, etc. which are signs of big back pressure changes.

 

[moorenycc]

By the way, I definitely did the mod for sound reasons only. Not for performance. The bike seems to run exactly the same as it did before the mod. My wife would have killed me if I spent $1,000 on an aftermarket exhaust system.

 

[dart1963]

when I did this mod I used a small sized hammer. You don't need a huge hammer or much force to punch through. I personally believe that there is not enough change in back pressure to cause fuel delivery problems. There is definitely more exhaust air flow now, but no popping, back firing, etc. which are signs of big back pressure changes.

Guess it would really depend how our exhaust is set up, if you are just punching out the exhaust pipe a little sooner from inside the final chamber, then I doubt it will change the backpressure much, but would change the sound.

Thanks for the heads up and if anyone else plans on doing this, a before and after is more useful. It's really hard to get a feel for sound as laptop and desktop speakers play into it (I even think the two bros sounds like crap on any of my pcs. speakers, but a before and after from the same distance, that give a comparison.


Thanks for the vid showing what you did moorenycc!

 

[cavcuz05]

ill have my set up for sale in the near future...including map...so you wont have to pay for all of the dyno tuning and labor spent on the header

 

[Spunky99]

Hi everyone,for what it is worth I am a licensed mechanic, this mod at the very least will reduce some back pressure, which will have an effect on low and medium range power response. The FZ6R exhaust is an integral component as to why the engine makes a linear line on the power curve. Normally the fuel flow via the fuel injection and valve timing would need to be altered to make up what would be lost with the reduced back pressure. Making more noise and loosing a bit of power is what you will gain. Is it really worth it? Depends on what you really want. Not attracting attention is the way I'd go.

Qualifications noted: You are not a power plant Engineer nor an exhaust designer so I take your qualifications with a very large grain of salt and thank you for your input. Sounds like good sound experience and real world knowledge.

After you have done the modification yourself, feel free to chime in on the perceived change...then after you have spent several hundred $$ on dyno testing, feel free to provide the new linear graphs....much appreciated.
(kidding with ya Man....)

I felt zero change after the mod from idle through 11k. There could be a loss in power in the lower RPM range but it's hard to tell. The R's build slightly quicker during hard acceleration. The throttle response is tepid until the engine is fully warmed up so I bet there was some pressure loss. Whether the pressure loss affected the engine fully warmed up or just the engine in a cold state for emissions is a question.

Unless someone has the map of the hidden compartments in the muffler I just busted through...any advice is as useless as tits on a boar hog regarding pressure loss, power curves etc.

The setup is louder and that was the objective. Besides, I am building a whole new exhaust system with Power Commander or Juice Box depending if I can get free power settings for the PC.

 

[Blue-Sun]

I can't bring myself to raise a hammer to something that I just paid almost $7,000 for... My FZ6R is my commuter and toy, and although it is a little on the quiet side, I can't see myself attempting to remedy this situation with a hammer and a couple of screwdrivers.

I think the last time I used a hammer on my car was a body hammer and dolly to straighten out some sheet metal.

I just can't hammer on a precision machine. Remember we are talking about a Yamaha motorcycle, not a Briggs and Stratton lawn mower.

Just my 2 cents...

 

[DocFZ]

I performed a free 5 minute exhaust mod on my FZ6R today using 2 flat head screw drivers and a hammer. This mod retains a stock exhaust appearance. Here is how I accomplished it:

1) I took a long, thin flat head screw driver and placed it into the exhaust outlet as for in as it would go in. When the screw driver bottomed out and would no go in any further, I hammered a hole/slit through the internal baffle using the screw driver. I then spun the flat head screw driver 90 degrees and hammered another hole/slit in the internal baffle (you can see what you are doing by using a small flashlight). Now at this point, if you shine a flashlight inside the exhaust outlet, you'll see a small "X" shaped hole in the internal baffle from punching the screw driver through it.

2) Now take a much larger flat head screw driver and do the same thing, making the internal hole bigger. Begin rounding out the hole on the inside. I continued pounding and working the metal ultimately until I had a smooth, internal hole about the size of a quarter.

The sound is fantastic (but not too loud) and is comparable in sound to the other popular exhaust mod done on this forum. I have ridden the bike slow, fast, hard, and I have no popping, back firing, rattling, etc. It sounds great!

For an even louder sound than mine, all you would need to do would be to continue working the hole larger and larger on the inside (maybe the size of a silver dollar)- or even slightly larger until you reach the desired sound.

Best of all, it still looks 100% stock. It is even hard to tell I did something when shining I flashlight into the exhaust outlet!

I'll try to post some pictures soon.

What I did was the same with the screwdriver, then took a long 3/8 extension and hammered that in, then flipped it to the bigger side, then a 1/4 extension and then flipped that. Its alot louder, but I still want a full exhaust

 

[yellowfz]

Hmmm, guess my comments are to truthful.
Again I program automotive computers and can tell you that they can do small adaptations for small changes such as this mod.
Trust me automotive control modules are much more complex than these bikes.

 

[fz6rwolf]

I've done this to a couple of past cruisers I've owned with no real performance issues. Now the vtx1300c I used to have when I put Cobra lowboy staggereds on and took the baffles out there was some low end torque loss as it was straight pipes (loud as all get-out too when I twisted the throttle but not too obnoxious in residential nieghborhoods using throttle and gear selection).

 

[husker525]

I found this thread to be quite entertaining. I would encourage one of the members who has swapped out their stock exhaust to take a band saw to the stock catalytic converer, showing a cross section.

The OEM cat is a maze of honeycombed chambers with a zig zag through each chamber consisting of the outlet pipe. The mod merely penetrates the outlet tube, and into one of the last, also of many chambers.

In theory, yes, backpressure will be reduced. This exhaust is very corked up in stock form, and has to be to pass C.A.R.B, emissions and factory DB limits. The amount of backpressure lost at the location of this mod, would be so minimal, only a dyno could detect it. The perverbial butt dyno would not.

The stock ECU will compensate, and can have some adjustability. A Yamaha dealer will NOT tell you how to crack into it, due to liability reasons, unless you know someone very well.

My prototype exhaust is the same shape externally, as the OEM. It has less chambers, and much less restriction. The stock ECU compensated for this with no problem, but when the heads were ported, I had to have more adjustability, and with the addition of NOS, I needed to change maps on the fly.

As for an actual dyno run, I dialed in the A/F at 13.6 with the stock exhaust. With the prototype exhaust being about 80% less restricted than the stock exhaust, it bumped up the A/F to around 13.8. It lost .1 hp from 2k-4k, and made an additional 11 hp from 4k to 9700 rpm.

Abbreviated: Punch away, but don't get crazy. You won't lose anything really, but will gain the noise you are looking for.

 

[Mikester88]

DON'T DO IT!! DON'T DO IT!!!!! I reapeat DONT!!! I did and it messes up back pressure. My acceleration went down. Can't even pop it up in first like I used to!!!! To top it off, it isn't even louder!!!!!! Just lower pitched. I just finished doin it, took it for a test drive and decided now I need to go get my TBR exhaust TOMOROW because I'm so dissapointed with my bike right now

 

[CDN6R]

Hey man that sucks...sorry you are not happy with it. I am tempted to try it but,,,,,

 

[Yellow09FZ6R]

Well my .02 I feel like a lost a little low end, but its very very hard to tell if I did. Its a sport bike motor and isnt supposed to have gobs of torque down low. I do feel that I have a little more pull in the upper revs, but like stated its a sport bike motor, its supposed to pull hard in the high rpms. I have always told someone its hard to feel a difference in exhaust mods, because it gets louder you really want to believe you gained something, but most of the time if you did, it wasnt much.

On a side note though, after sturgis I have over 1000 miles on the bike, and thats a HUGE increase in power. Everything is nice and loosened up now and she runs like a champ. On the way back I did a quick 65-120 pull when I had room without any traffic. Felt good but it wasnt quite as heart racing as doing 190 on my last litre bike.