Standard pipes - nice note

[Abe]

I didn't wont to buy new pipes, and I love the sound of my 1100 with staintunes.

So a quick search on our sister forum, ST-Owners and found exactly what I was after.

I did this to mine and Sicmans prior to Ballarat.

Difficultly = easy

Even easier if you ride to my place and I can do it for you while the pipes are hot (pipes must be HOT), no need to get off the bike if you are in a hurry.

IMPORTANT - it has not effected my fuel usage either way.

Start off with a smaller pointed rod and place in the centre of the hole, very important, then a slightly larger one, and finish with 18.5mm with a large thick washer welded to the end, to aid in removal (do same to all rods) Also need a decent hammer (lump hammer or similar) earmuffs and safety glasses (OH&S).












That mark is to stop you going through the front of the silencer.

End result, standard pipes with a nicer note.

Yes I will record the sound, when bike back together.  Farkling at the moment.

[Turtle]

That looks painful Dave

And yes before and after sound please I may be interested

SM Turtle

[Abe]

No problems, BUT, can you do the before  (I can't) and I'll do the after

Will post the current sound tomorrow 

I must say the note is nice and keeps the original Honda look, and sounds great when you power on.

PS. the pain goes away after a couple of days

[Turtle]

I can't start mine waiting for a fuel hose from the states

Be in a few weeks

Anyone else can they record?

Turtle

[Abe]

OK Gavo, i'll do a recording in the morning EST.  The battery is on charge (flat battery) been fitting farkles without starting the bike  .

Try not to get to excited over the new note the pipes make 

Sounds great when you are going down hill (have you hills over there) and back off the throttle fully. 

[Brock]

We do have a hill over here, its not too bad as you can get a pushbike up to 10KPH before you hit the flat agin

[Abe]

Hope this works?

Starting cold:-
2 bars on the temp. and sitting at 4000RPM

[Pocket STocker]

I dont know what I was listening for exactly, but i must say for you, you neat freak  That muffler is a bit grotty 


And dont make the excuse the your loverly wife has not had the time to clean it for you yet 



Pockey 

[johnnyYTED]

 
   have you done it to an ST1100.. I did a similar thing to my GPz 11 years ago, and it made it growl,  do you think it would make my ST11 sound better?

[Abe]

I dont know what I was listening for exactly, but i must say for you, you neat freak  That muffler is a bit grotty 


And dont make the excuse the your loverly wife has not had the time to clean it for you yet 



Pockey 

The bride is going to clean the bike after she gets my breakfast 

[HunterTodd]

Gentlemen,

I would like my ST to sound a little aggressive as well but as someone who did his time at the Repco muffler factory in Sydney. (I worked on the testing of the  mufflers for the VB Commodore that is how old i am!!) I would suggest you need to be a little careful poking holes in mufflers with out knowing the internal construction. If it is a baffled muffler you could open a hole straight through.

It might be an interesting tech project to get a damaged muffler and cut it open to see how the flow goes. And from there we maybe could work out a procedure.

The engine ECU mapping is also expecting a specific amount of exhaust back pressure. You may find punching holes has an unexpected effect on performance and/or fuel economy. Be aware more flow is not always a good thing.

I haven't look closely at the mufflers but it may even be as simple as opening a hole just inside the pipes which exit the muffler. Next time I have one off I will send my Aldi boroscope on a discovery mission to see what they are like inside

[Abe]

Here is some sound clips of various exhausts form ST-Owners 

http://www.st-owners.com/forums/showthread.php?46675-Exhaust-Sound-Clips

HunterTodd,
I looked at several very informative sites and one rider pulled the original silencers apart removed baffles and had it welded up again.

ECU mapping doesn't need to be adjusted going by previous posts.

I have used a boroscope and it was the same as previously posted on ST-Owner site.

I would be interested what you think when you have a look.

Economy has remained the same for me, but others say they have an decrease in fuel consumption (riding style perhaps??)

I'll try and find the sites if you are interested in reading further 

[Sicman]

Since Abe did mine I have noticed better fuel economy, although that is balanced by my twisting the throttle more cause they now sound better 

[HunterTodd]

I no expert Abe I was only the dumb assed apprentice who made the mods to the mufflers which the engineers suggested.

They had the old Dummy Door on the rolling road and and tested about fifty combinations of baffles and  fill material until they got it right,

One of the more interesting things was what happened when they deliberately provoked a backfire. Most time it just about destroyed the inside of the muffler. Split all the tubes and buckled the baffles.

I am surprised about the mapping. We do a lot of work with diesels where I work and the amount of restriction has a big effect on them. So much so that if the back pressure rises 10 or so kpa they shut the engine down because the emissions are too high. I know you are going the other way but I would have thought it effected it.
Might be peculiar to diesels.

Good to see some one has had a muffler apart though. Helps to know what is inside. If we were serious about it we would probably dyno a bike before and after.

It would be interesting to hear your bike in real life.

[saaz]

On closed loop (using the oxygen sensor to maintain a set AFR - cruising and most normal riding) it should not affect things. When the system goes open loop (accelerating etc) it is possible for exhaust and intake changes to require ECU remapping.

 I know my car benefited a lot when remapped to suit a far freer flowing exhaust (25% power gain so not minor)

As the intake restrictions are still in place with the modification some minor changes to the exhaust might not need remapping. The bike might just feel a bit more responsive. As well, the ST1300 ECU is a bit of a mystery (powercommander cannot do a tuning module for it) so I assume it has a learning mode built in that adjusts the tune depending on what the oxygen sensor reads. In the Holden/Chev world this is called long term fuel trims, as the ECU learns what changes have been made. If the changes are not too big the ECU will adapt the air fuel ratios to suit at all throttle openings over time.

[Turtle]

Wish me luck I'm off to bunnings for a loooooooong large nail

Turtle

[Abe]

You may need to buy 2 loooooong big nails, as you have 2 mufflers   

Take care over there SM   

[gaz]

 

[Turtle]

Ok issue Bunnings don't sell nails that size or mitre 10

Dave advice please on your vampire nail where to purchase 

Turtle

[Abe]

Made my own 18.5mm was the last pike size.

I just used rod that I had lying around.

Simple, just ride over and will do (the mufflers, that is) for you.   

But you bring the beef jerky as payment 

[Turtle]

Meet me at the Border next month for a beer and I will bring you some jerky that's fair 

Turtle

[Pezzz]

Turtle,  get some threaded rod from bunnings the right length then grind a point onto it.

Sent from my GT-I9507 using Tapatalk

[zevk]

I really hate to be a KILL-JOY  but... I have done this exact mod on a Honda VT750 Shadow. It DID increase the sound to a louder, low end rumble, BUT....
3 mechanics REFUSED outright to provide Vic RoadWorthy certificate as they MEASURED the db  and knew I had hole punched the baffle, even though it is not a visible mod....

its the oldest trick in the book!

The only way to get roadworthy for selling was to WELD a restriction plate over the baffle area, which requires removal of the muffler from the bike (for the remote, but real risk of weld flash of piston to cylinder wall / head and / or frying the voltage regulator /  ECU.)

Punching the baffle took 3 minutes, repairing the hole prior to sale took 2 hrs and $150....

BTW NO significant benefit was noticed in power at all on that bike and I doubt if any improvement would be noticed on the ST1300 

IF you are planning to keep the bike for many years, I feel it is better to invest $600 in an aftermarket new, quality muffler (Akropovic, Staintune etc.) as they all have REMOVABLE decibal killers (silencers) and will pass ADR / Roadworthy...

my 2c, good luck 

[Brock]

No annual checks in WA, and I dont know of any checking station that has a Db meter (calibrated) or the proper set up for doing the test

[zevk]

Lucky WA, Vic is strict, well at least Eastern suburbs of Melbourne 3 shops i went to...my own experience is that once the bike is up on the lift, you are at the mercy of the mechanic to sign your roadworthy    and usually you don't have time to waste, as you need the bike sold asap...so you can buy another bike