After market cans?

**vifferman** · 1st September 2004, 16:35

Originally Posted by Cajun

Nah wife says she wants to make it louder, she had bike 2 years and its total stock apart from rebuilding the rear shock from new to lower the seat height by 4 cms so she can touch the ground better

Yep give us any info you have on doing, i have one site, but wasn't that good, any more info would be good

The best site is this:
http://www.burniemorgan.com/motorcyc...ml#bafflectomy

Some of the info is wrong (like it does result in a slight power increase, if you adjust the jetting), but it's not bad.

As for plugs to satisfy the spirit of the law if not the letter, what I did was went to a muffler shop, and asked them to weld up two plugs to a plan I drew. From memory, the outer pipe is 57mm (2 and a quarter inch) diameter by 60mm long, and the inner pipe was about an inch (25mm) by about 120mm long (now about 75mm). Welded between them at the inside end is a washer of sorts, and the inner pipe protrudes into the muffler. Thus you end up with two concentric pipes, joined at the end of the larger one by a washer or plate. Hard to explain in words, but easy to draw and to make.
The outer diameter of the plug is just slightly smaller than the end of the muffler, so I coated the outside of the plug with high temperature silicon, slid it in, and waited for it to cure. THen I ran the bike, removed the plug again, cut some of the inner pipe off, and did this a few times until it sounded OK.

**Milky** · 6th September 2004, 21:32

my exhaust has now had some modifications done to it. It is running much smoother, quieter, more efficiently - i think with much less fuel consumption too

The solution was to fit and test little things until they came out the way I wanted them... I started out with pressing a washer at the end of the exhaust pipe, just before the can. This was about 30mm or so internal diameter, fitting into a pipe - which I forgot to measure

Outside diameter is ~52mm, so it is rather too large for a 400 i think.
This made quite a difference, and removed a flatspot from 6-8k and made a deadspot at 4-5k. Much improved delivery through the middle of the power band up until near redline, where it wasnt quite as responsive. I dont get to 14k too often, so overall it was a great improvement. Still sounded nice, just took a little of the resonant bass out, and made the pulses from the end of the can slighlty less distinct.

Thought I'd try it with a bit of perforated pipe that we had left over from another muffler 'bafflectomy.' I think the pipe was about 35mm diameter. I really should have measured these things before it got welded in place...

You can see it in the photos anyway and make your own judgement. Stuck that on the end of the large washer with a locating pin to hold it centralised in the exhaust, tried it again...
Found it made the deadspot at 4-5k was less so, more of a roughspot instead. Other than that, much the same as before.

Thought to myself: "If restriction improved it, then obviously, more of the same will make it even better"

So I found a little washer that happened to fit the end of the perforated pipe, tacked it on with some locating pins again, and tried once more.
The result was a considerable decrease in roughness from 4-5, greatly increased torque, and an overall increase in usable power. Yay for intuition

It is different in sound, less of a bassy thump... More like a 400 than a 600/750 now. Still howls nicely higher up in the revs

. I can hear the camchain and the valves at idle, which is reasurring... I hope the reduced volume takes some attention away from my less than perfect changes, possible law breaking and general misdemeanours too

Pics of the finished article follow. Not a work of art, but it aint going to be seen by anyone apart from the exhaust pixies, so I figure it doesnt really matter...
Thanks to KK for inspiring the maori in me

without you, I would never have started...

**Kwaka-Kid** · 6th September 2004, 23:15

hhaha WICKED mate! thats has like 10x the workmanship anything of mine ever has!

Top effort and exactly what i need to do to current muffler to get more usable power. or any at al.

And milks mate - pllease tell me that muffler has some muffling? Its not dead hollow with only metal in it is it? you did buy some of that muffler mat right?

**Dodgyiti** · 7th September 2004, 14:41

When I first purchased my bike it came with ' shadow' mufflers.
In other words- When the sun shines on me bike, the shadow gives the impression that it has a full muffled exhaust system, and that is as far as it goes. I take the bike to the place where I bought it from for WOF's, if they passed it before I bought it, then they have to keep passing it?

[earplugs essential]

**brit_vtr** · 7th September 2004, 20:59

Hello,

I have a Firestorm and run a single exhaust on the right hand side, it sounds a little quieter than my old twin Vipers ....but the bottom end and midrange punch is absolutely fantastic.
Add a 15 tooth front sprocket and it monos in the 1st 4 gear no trouble.
As for the sound well it's just sooo nice, deep like a Duke but rises to a 4 cylinder howl.

**Milky** · 7th September 2004, 21:10

Originally Posted by Kwaka-Kid

hhaha WICKED mate! thats has like 10x the workmanship anything of mine ever has!

Top effort and exactly what i need to do to current muffler to get more usable power. or any at al.

And milks mate - pllease tell me that muffler has some muffling? Its not dead hollow with only metal in it is it? you did buy some of that muffler mat right?

The can has muffler wrap around the perforated pipe I guess. If it doesnt, then the guy I bought it off was telling lies... I havent taken it apart, so I wouldnt know for sure.

I bought nothing for this job.

**Kwaka-Kid** · 8th September 2004, 00:01

wicked mate! thats the stuff! well my new carbon fibre exhaust just arrived! when i say new i mean scratched up and been down the road by some aussie but new to me and looks good enough for my standerds! so on it goes for raceday

**Firefight** · 10th September 2004, 08:33

Just fitted my new Micron (last night at work), had a nice long ride home, Mangere to Pukekohe(via 22 and the waingaro springs), Shit is it cool, looks good, sounds good, and seems to have improved the overall perfomance a lot.

thanks Ducan @ Amps, for the good service and good advice.

F/F

**SteveNZ** · 11th September 2004, 19:26

I've got a Neptune can on my SV650. I had a removable restrictor made up for it to quieten it down a bit, as with my replacing the airbox with pods, it can get a bit loud when it's on-note (anything over 5500rpm) otherwise. The restrictor is one that Mark at Neptune makes, IIRC it was $70-ish. I had to go buy a decent drill bit to put the hole for the retaining screw - Mark actually gave me one, but it couldn't cut it (as it were). The fact I was using a budget drill probably didn't help.

I've even got a picture of my SV on his site, complete with the pretty orange/brown exhaust pipes that the SV develops...

Anyway, Mark is a top bloke to deal with, and the product is excellent. Looks good, sounds good. Gets rid of the big hole in the powerband around 5000rpm on the SV due to the poxy catalytic convertor...

**Zed** · 11th September 2004, 21:12

Originally Posted by Firefight

Just fitted my new Micron...

Excellent, I look forward to seeing & hearing it...it's like riding a different bike eh!!

**Sensei** · 12th January 2005, 19:33

Straight through for me does the trick nicely
SENSEI

**SPORK** · 13th January 2005, 09:00

So how illegal would it be to slap on a nice CF can? Would noise be the only restriction?

**vifferman** · 13th January 2005, 09:23

Originally Posted by madcat_

So how illegal would it be to slap on a nice CF can? Would noise be the only restriction?

Apparently, the rules regarding zorsts are being (or have already been??) revised by the LTSA. Again. So who knows.
CF cans are somewhat trendy, but not particularly durable. Apart from requiring repacking, the CF becomes brittle, and is degraded by UV quite badly, discolouring and degrading.

Now that I've got a new bike, I should vote again on this. The VifFerraRi has a Staintune high-mount, with the spud installed. It's probably no louder than stock (one review I read of the stock VFR800 said the can was a too loud), but looks much nicer, and has a nice tone.
I've ridden it a few times without the spud, but it sounds... I dunno. Irritating, perhaps, and makes no discernible difference to performance.
The best sound apparently is obtained by taking the spud out, cutting the tail off, and reinstalling it. If I did that, I'd be in trouble with the vifferbabe, unless she didn't notice, which is possible.

I must take the factory-fitted noise compliance sticker off the bike. It states that the bike has been tested and is less than 89dBA (IIRC), but also states what the ID number on the muffler is, if it was still there....
Best to remove it, so there is no possible "Ello, ello!" nonsense in the future if some bureaucrat looks for the ID. Staintune make compliance tags for their zorsts for the Australian states that require them, so I can always order one of those, if necessary. With the spud, it should pass any new regs anyway. Dunno 'bout the loud whining of the camgears though...