STock Exhaust Modifications.
- Thread starter 100MPG
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OP
OP
100MPG
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I have gotten 45-52 mpg on several tanks in a row so I do think the MPG's are a little higher with the modified pipes...
do know where the cats are located in the muffler and what type bb's or ?
is your st a 2008 thanks
is your st a 2008 thanks
Smallville
Scott
The cats are located in the front of the muffler where it starts to get larger. They run from the large round part back into the triangle part. It is the honeycome type cat.
NCrider
Andrew Seawell
I'm interested it this for heat reason.
The heat if fine everywhere else, but my feet cook....and yes I wear nice thick boots.
Did it help the heat at your feet?
The heat if fine everywhere else, but my feet cook....and yes I wear nice thick boots.
Did it help the heat at your feet?
picked up a pair of mufflers and pipes cheap on ebay, own a v65 sabre and love the sound of it, will try the punch through mod myself here shortly. Was originally thinking of gutting the mufflers and packing them slightly with some high quality steel wool similar to the way glass packs used to be packed.
Hi, thanks for this post, it, in my opinion, is a very educating post.
To start do you really think it increases mpg? I believe taking out the cat. con. is the key element here. It is the first and the most constrict ant here.
I am thinking the back pressure is the factor of the low mpg. It is totally relevant to the last diameter of the exhaust exit, in this case those two little holes at the end of the each pipes.
I am thinking to drill very small holes not only to the inside of the both end holes to the pipe but also to the back part of the exhaust pipe where two holes are. So that will increase the end diameter of the exit. Thus reducing the back pressure.
I cant cut and weld the same section of the pipe to take out the cat. con. I need to find out a different way to fix the cat. con.
Since you take out the whole thing, can you please provide us a diagram about how the pipe is designed? I found one in the internet but it is not detail.....
I need to know how the gas travels, and what is the purpose of those little holes on the outer side of the exhaust walls?
I checked and find out that if you close the holes underneath the exhaust drain holes (the water drain holes) the sound of the muffler gets less louder.
Please, when ever you have time, the diagram will be appreciated.
To start do you really think it increases mpg? I believe taking out the cat. con. is the key element here. It is the first and the most constrict ant here.
I am thinking the back pressure is the factor of the low mpg. It is totally relevant to the last diameter of the exhaust exit, in this case those two little holes at the end of the each pipes.
I am thinking to drill very small holes not only to the inside of the both end holes to the pipe but also to the back part of the exhaust pipe where two holes are. So that will increase the end diameter of the exit. Thus reducing the back pressure.
I cant cut and weld the same section of the pipe to take out the cat. con. I need to find out a different way to fix the cat. con.
Since you take out the whole thing, can you please provide us a diagram about how the pipe is designed? I found one in the internet but it is not detail.....
I need to know how the gas travels, and what is the purpose of those little holes on the outer side of the exhaust walls?
I checked and find out that if you close the holes underneath the exhaust drain holes (the water drain holes) the sound of the muffler gets less louder.
Please, when ever you have time, the diagram will be appreciated.
I measured a 2006 model LEFT exhaust with the heat shield and it is 12.5 lb.
I measured by itself and than with my self to be more accurate. Both times it read 12.5 lb. I believe heat shield is no more than 0.2 lb so it can be left out.
I measured by itself and than with my self to be more accurate. Both times it read 12.5 lb. I believe heat shield is no more than 0.2 lb so it can be left out.
Cool post, thks. Ive got a '10, about 40k on it, and am considering this mod. First and foremost hoping to cure the shim/ankle combustion issue. Doggone these bikes cook the legs, dont they? Have you noticed any improvement in this area? Less back pressure I would think would mean less heat retention. Any info on mileage, and fuel computer related problems from the mod? Ive still got a year of warrantee to go, but if the mod is a winner, will go ahead and gut the cans. Thks again!
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Have you got pictures for the muffler, contemplating the same project myself, but be good to see for a plan first.Well, it is done.
I will make this two posts, first is the actual modification work, second is the sound of the ST.
I bought a set of mufflers off of ebay, $32(what a STEAL!) and shipping was $40(huh?) So far $72.
I happened to find a great welding/Fabrication shop right across the street from work. When I say find, it is a strip of mall stores, but it is two rows, and I never have looked at the second row. Someone told me to check the Prop shop, a high performance boat prop company. They work with a fabrication shop in the second row, who does their bimini's and other aluminum fab work.
He welds anything.
Perfect.
I talk with Ed, the owner and tell him what I want. Cut the front of the pipe, behind the Cat, and I will take it and perform the various unknown mod's to the pipe and then bring it back and he will then weld it back together. $100 each pipe. For me it is worth the attempt. Deal.
I drop the mufflers off with him, he will call me later that day and let me know they are done and I can pick them up. Later that day, no call. Next day no call. I stop by the shop and he is just going in the door. Long story short, he could not get to it, and he will do it right now. Great!
It was a little rough finding the exact spot were the seam was, but the second one was cut in about 15 minutes. First one took an hour!
After we get the first one open, shock, amazment and respect for the quality of honda products. This muffler is built like it has to go to MARS on the next mission! They could upscale this muffler and attach it to the space shuttle and no one would know it was taking off! It is really well made, stainless BAFFLE screen inside, heat barrier between the inside baffle set up and the outer case. I was impressed.
Cut the first one open. The screen was already cut open with a plasma cutter so I laid it back in for a pic. I TRIED for 30 minutes to hack and chisel it out with little (none) success. Plasma? 30 seconds.
Behind the screen was a SOLID (originally flat...) plate except for one tube that went to about 3-4 inches before the end of the muffler, which ended in a chamber. (continued after pic)
From that chamber one tube (the medium size tube) came back towards the front of the muffler, into another smaller chamber, then out through the two small tubes and out.
So at this point, I am wondering why the heck I am wasting my time and money. They will be too loud, since it is basicly a straight through pipe now, with very little muffleing ability.
I am commited so I might as well smile.
After a long time hacking and cutting and hammering (if you try this yourself, skip the hammer part, it is a waste of time) They are ready to be welded.
Ed, welding. The first muffler that we cut, was not a clean cut since Ed could not tell were the joint was. So while the second muffler was welded in less then 30 minutes, the FIRST muffler took 2 HOURS! The gap was too large, so it was weld, fix, weld, fix, weld....and so on. I gave him the option to finish it tomorrow, even though I really wanted them done, he said he would continue so I didn't bring it up again.
This is the seam and lip.
The first done muffler. I forgot to take a pic of the POLISHED, finished mufflers, they look AMAZING, but here is the muffler, finished but with rough welds and DIRTY.
I will take pictures and add them here, but I will tell you now, they look great! I was very happy with the results.
Next, the Sound of ST.
Many thanks Rogue
Note........
100MPG's post is from 2007....and he hasn't been here for about 5 year.
If you weren't in NZ, you might have been interested in a set of Staintune I am thinking of letting go. Am too used to the quiet OEM.
I thought it was a long shot, keen on a set but no one sells them in New Zealand, we are a bit of a secluded island, great place to ride though.
If it wasn't moon beams to post from there I would be interested in a set, second hand is fine, as my bike is ;-) . Wish I had found these bikes earlier, it's just a dream to ride, possibly the most comfy tourer I've had!