Supertrapp snuff - $0.

[Motu]

I knocked 5 db off my Supertrapp today - read all about it here.

http://www.advrider.com/forums/showt...33#post7087133

[NordieBoy]

Hmmm...
The original IDS endcap is a lot quieter than the IDS2 as well.

But yeah, the quiet cores are expensive.

Might have to give this a go on mine

[AllanB]

Well done.
Not wanting to put a downer on it but the WOF standards will now not allow adjustable mufflers. They are fine if the db killer, outlet etc is permanently attached - a rivet or weld is considered permanent a removable screw is not.


Also to shut it up as 100db is very loud and even 95 pretty rowdy. Can you repack it? if so the old packing i most likely blown out.

Buy or make yourself a db killing insert. They work surprisingly well. Easy to make with scrap exhaust tube and you strike me as a innovative chap.

[Motu]

They have never allowed adjustable exhausts...but the wording had been changed to switch or lever.No switch or lever on a Supertrapp.

[Disco Dan]

I knocked 5 db off my Supertrapp today - read all about it here.

http://www.advrider.com/forums/showt...33#post7087133

Great post, I was interested in the last comment though about how having a temporary silencer for warming up early in the morning so as not to wake up half the street.

That way if it was just for that purpose it would not matter what it looked like or how big/bulky it was - the noise reduction would be the importance.

I must admit I have never thought about how an exhust works to silence but I understand it would have something to do with altering the direction of the air through lots of channels rather than a free flow style?

Bearing in mind bikes generally idle about 800-1100 rpm compared to a car which is much lower and only a couple of hundred rpm.

It would also need to be put on/removed easily and quickly without burning your hands or scratching the chrome of the stock pipes.

Any ideas?

[FROSTY:Me]

Well done.
Not wanting to put a downer on it but the WOF standards will now not allow adjustable mufflers. They are fine if the db killer, outlet etc is permanently attached - a rivet or weld is considered permanent a removable screw is not..

Off topit a tadd---I wonder what effect thats going to have on two stroke riders ?

[AllanB]

Yeah this is the bit where you hope you do not get a WOF Nazi who does not understand why the baffle on a two-stroke should be removable.

I had Dunstall replicas on my old 750 twin a few years ago and the core was removable to allow repacking. At the last WOF I was told that the mufflers should fail as the cores were modifiable. I note you can still purchase these mufflers.

I politely pointed out that the purpose of that was to allow repacking and that I had in fact removed them, repacked them with a superior packing AND fabricated an insert into the core to make them quieter! I offered to remove them to prove this if he desired.

He smiled and quietly ticked the box.

I've noted that arguing with them is a waste of time, bring along facts to back up your reasoning if required and you will be fine. I carried the NZ requirements for braided lines around with me on that bike for that reason.

[NordieBoy]

Bearing in mind bikes generally idle about 800-1100 rpm compared to a car which is much lower and only a couple of hundred rpm.

Stock idle on the DR650 is 1500rpm - Nice 'n thumpy through a SuperTrapp IDS with Race Core.

[dino3310]

great idea motu, looks good aswell

[vagrant]

Great post, I was interested in the last comment though about how having a temporary silencer for warming up early in the morning so as not to wake up half the street.

It would also need to be put on/removed easily and quickly without burning your hands or scratching the chrome of the stock pipes.

Any ideas?

I had a length of old radiator hose attached to an old car muffler. The hose slipped over the bikes outlet stub. Easy to fit and remove, and kept the VFR to a nice quiet burble while warming up on the choke.
Then it was choke off, muffler off, and quietly idle off down the drive, before giving it the berries up the road

[vagrant]

Well done.
Not wanting to put a downer on it but the WOF standards will now not allow adjustable mufflers. They are fine if the db killer, outlet etc is permanently attached - a rivet or weld is considered permanent a removable screw is not.

Is this applicable to designs such as Zorsts, http://sites.yellow.co.nz/site/motor...stspecialists/ with the adjustable baffle plate inside, or just the removable plates that cover up the small rubbish bin that some people are using for a muffler these days.

[Wired1]

I was about to start a thread on just this subject so excellent timing. My SR400 rebuild took a nose dive today when it failed a re-cert WOF for lapsed rego. One of the two main failures was for "excessive noise exhaust". I'm running the supertrapp off my TT500 and although it was a temporary measure I like the look of it and would like to keep it on the bike.

So the photo's below, what I want to know is how to shut the fucker up just enough to keep the VTNZ happy. Looking at the other ideas around here I'm thinking of making a slip-on cover to go over the back end and a 45 degree down-bender at the end - what do you reckon?

Does removing the plates make it quieter? Should I repack it and with what? I've been told (by my boy-racer apprentice) that batts are a good filler!

[Taz]

Motu, Is the dry clutch on my ducati gonna push me over the limit? Gets quieter if you pull it in but will that be allowed?
Andy.

Can I come down some day and get the noise tested?

[NordieBoy]

Does removing the plates make it quieter? Should I repack it and with what? I've been told (by my boy-racer apprentice) that batts are a good filler!

Batts will work - for a while. Proper mat/fibre is cheap though.


Run it with 4 discs.
It'll be a lot quieter and have a bit more torque.

Once you've got your reg/wof then put the discs back in so you can reach the speed limit though.

[sAsLEX]

Is there any one in New Zealand who can test vehicles to the appropriate international standards for vehicle noise.......... or is it still the NZ hick test method Andy Cockerhead bought in a while back?