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Old 26th September 2010, 14:37   #166
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YUP. Thats the open able one with the glass-wool filling.

Thats the one slowly getting popular. I enquired at one place, (shivaji nagar) and was quoted 2800 rs to get one of them. I thought it would be economical to convert the one which i have in to something similar to your pic. Thats what the next step is. I would prefer the sound to be more bassy, and not too loud. Right now, its too loud for my ears. What should be amount of glass wool to achieve the same? how does the proportion of glass wool affect the sound?
Also i am sfiguring out as to how to mount a free flow K&N cone filter (No 1100 i think) on the C5 to richen the AF mixture to avoid possible damage to the exhaust valves. (hope the FE does not drop drastically)

With the goldie ON, i found slight drop in initial pickup. What could be the reason?
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Old 26th September 2010, 15:44   #167
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Quote:
Originally Posted by nasirkaka View Post
Thats the one slowly getting popular. I enquired at one place, (shivaji nagar) and was quoted 2800 rs to get one of them. I thought it would be economical to convert the one which i have in to something similar to your pic. Thats what the next step is. I would prefer the sound to be more bassy, and not too loud. Right now, its too loud for my ears. What should be amount of glass wool to achieve the same? how does the proportion of glass wool affect the sound?
If at all you are planning to buy one, get it from Shakeel. My roommie bought the shivaji nagar goldie and the build quality is not up to the mark as the pune one.

I think the more glass wool you stuff in, the lesser the beat will be. But the problem is that the glass wool would reduce the sound at all RPM ranges. So when I made the high rev sound of my goldie bearable with the glass wool, i lost some low end base. I used half of the glass wool from the pack I got with the goldie.

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With the goldie ON, i found slight drop in initial pickup. What could be the reason?
I remember someone here saying that putting a Goldie will reduce your low end torque, due to reduced back pressure of a FFE compared to the stock one. (But this is contrary to my experience, I felt my low end torque the same even after moving to a FF setup).
Loss of initial pickup, hmmm.. What does your spark plug tip say?

Last edited by jingaboysr : 26th September 2010 at 15:47.
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Old 26th September 2010, 22:50   #168
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In a FFE where does the concept of glasswool come into picture?
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Old 27th September 2010, 12:10   #169
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Glass wool sits on the outside of the exhaust flow. Thus causing no disruption to the "free flow".

the sound waves propagate via the perforations in the inner tube - into the glass wool, where the higher frequencies get absorbed.
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Old 27th September 2010, 14:57   #170
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I had been to Sandhya automobiles in JC road recently. I asked him for goldie silencer. The silencer what he showed was the conical shaped free flow one and it didnt have glasswool. And there was no seperate chamber to fill in glasswool also.

Now after going thru this thread, i am not sure if what he showed me was the original goldie silencer or local one. How will we be able to differenciate among them?

I tried that silencer for few days. Initially liked it. At low rpms the sound is sweet and infact its very loud also. But at higher speeds, say 50+ i dont like the sound. It will be like the sound coming from one of the 2-stroke engines having a defective silencer!
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Old 27th September 2010, 18:35   #171
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Quote:
If at all you are planning to buy one, get it from Shakeel. My roommie bought the shivaji nagar goldie and the build quality is not up to the mark as the pune one.
Hey, my goldie is from the famous shakeel of pune. Just that i am modifying it here in bangalore.

Quote:
Loss of initial pickup, hmmm.. What does your spark plug tip say?
I am running on the stock bosch spark plug (heat rating 8 ). Have checked it 3-4 times in my 4500 kms of running so far and always found it to be more on the black side with carbon deposits.

Quote:
Now after going thru this thread, i am not sure if what he showed me was the original goldie silencer or local one. How will we be able to differenciate among them?
the original goldie silencers would be some 40 odd years old, and almost impossible to find one. What we generally get is goldie replicas. Within these replicas, there are design variations. I have come across 3 main variants of goldie replicas as follows:

1. A conical shaped exhaust with nothing inside. Fully free flow. This one is just looks like a goldstar (loosely) and produces the loudest noise. (read NOISE). typically costs between 700-1000 rs. In my opinion the most irritating of all. i think this is the one which u got from sandhya spares.

2. A goldstar type exhaust which has a perforated sheet metal baffle inside. This perforated sheet metal is is bent like a 4 petal flower (cross section).
This one make loud noise, but is not as loud or irritating as the first one, would roughly cost around 1500-1800 rs.

3. The third variant is made in two parts. The shape is similar to goldstar type, but the rear part of the exhaust is removable. ( as seen in the pic posted above by jingaboysr )

There is this outer sheet metal tube and inside there is another (lesser dia) perforated sheet metal pipe. Between these two there is provision to fill in the glass-wool and close the end. These type produce good sound (not too loud) and more bass based. Closest thump amongst three to a well tuned CI bullet. (however an AVL or an UCE can never match the thump of a well oiled / tuned CI std 350 with a heavier crank).

The cost ranges between 2000 to 3000 rs, depending on the city and the maker.

Last edited by nasirkaka : 27th September 2010 at 18:38.
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Old 27th September 2010, 22:51   #172
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Quote:
Originally Posted by nasirkaka View Post
1. A conical shaped exhaust with nothing inside. Fully free flow. This one is just looks like a goldstar (loosely) and produces the loudest noise. (read NOISE). typically costs between 700-1000 rs. In my opinion the most irritating of all. i think this is the one which u got from sandhya spares.
Exactly Nasirkaka. This is the one which i had. I just had it for a day in my bike. Very irritating one.
Thanks for clarifying my doubt about goldie silencer
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Old 1st October 2010, 02:29   #173
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Quote:
Originally Posted by nasirkaka View Post

2. A goldstar type exhaust which has a perforated sheet metal baffle inside. This perforated sheet metal is is bent like a 4 petal flower (cross section).
This one make loud noise, but is not as loud or irritating as the first one, would roughly cost around 1500-1800 rs.
The second one that you are referring too is manufactured by Sans Inc,New Delhi.....
They also Manufacture the Megafone Exhaust...
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Old 1st October 2010, 02:43   #174
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I don't know if that has been explained before. But I am writing it for benefit of all.

1. the simplest of the Free Flow Exhaust is straight tube (for 4 stroke motor) of "Tuned Length". This length and dia of pipe is arrived from following

a.) exhaust valve timing.

b.) CC of an engine

c.) Rpm, at what rpm do you want the max effect.

Thus it is critical to select the right rpm. And that is the reason some aftermarket pipes are good at higher revolutions than that at lower revolutions.

Secondly now since this straight pipe produces noise, we add mufflers (end cans). The one popular, perforated pipe with wrapped glass wool is simple, effective and least restrictive.

Also please note that a conical pipe will have no effect if inside there is a perforated pipe. The effect will all be that of dia of perforated pipe.

Increasing the back pressure in the system increases the torque?? Actually per see there is no need for that in a 4 stroke engine. 2 stroke yes you need back pressure.

Another thing is a sudden increase in dia of pipe will have drastic effect on the flow of gas inside the exhaust pipes and in some cases is beneficial.

And apart from that there are varios other factors, variations, regulations that come into play in designing a pipe.

I will try to explain more in my next post.
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Old 1st October 2010, 11:01   #175
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Originally Posted by manishalive View Post

Also please note that a conical pipe will have no effect if inside there is a perforated pipe. The effect will all be that of dia of perforated pipe.
I have a goldie which has nothing but a perforated pipe wrapped in glass wool inside. Now does this mean that the outer shape of the goldstar replica has no effect whatsoever on the sound or the performance?

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Increasing the back pressure in the system increases the torque?? Actually per see there is no need for that in a 4 stroke engine. 2 stroke yes you need back pressure.
True. I never felt a loss of torque at all. But many others swear otherwise.
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Old 8th October 2010, 15:36   #176
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Quote:
Originally Posted by jingaboysr View Post
I have a goldie which has nothing but a perforated pipe wrapped in glass wool inside. Now does this mean that the outer shape of the goldstar replica has no effect whatsoever on the sound or the performance?

True. I never felt a loss of torque at all. But many others swear otherwise.
Sorry for the late reply, I missed this post. yes perforated pipe with glasswool will act as a straight pipe. However the Glass wool will pose no restriction, it will only act as a sound absorber.

I think the goldie silencer is mimiking the look orginal megaphone one. Megaphone can be trick one to design, it works on reflecting back the pressure wave; negative pulse energy. The basic idea is to time the negative wave pulse reflection to coincide with the period of overlap - this low pressure helps to pull in a fresh intake charge as the intake valve is opening and helps to remove the residual exhaust gases before the exhaust valve closes.

There is a whole lot of theory involved, what may look good on the face of it might not even result in a single BHP gain.
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Old 23rd October 2010, 00:59   #177
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Quote:
Originally Posted by nasirkaka View Post
These type produce good sound (not too loud) and more bass based. Closest thump amongst three to a well tuned CI bullet. (however an AVL or an UCE can never match the thump of a well oiled / tuned CI std 350 with a heavier crank).

The cost ranges between 2000 to 3000 rs, depending on the city and the maker.
Dear Nasir and all the Bullet enthusiasts,
I own a 2007 RE Electra 4 Speed.
I love and respect my bullet for what it is and i have no issues/complaints.
My choice of CI over AVL was purely because of the thump that the CIs made in comparison to AVL. When it comes to performance, AVL definitely feels better than CIs.
My car is a Maruti Gypsy and my bike being a CI Bullet, its more than clear that i am not into speed I prefer riding it in 60 to 70kmph (super-light on the throttle).
I've had the chance to ride bullets from 80s to 2007. If i could improve the thump in my electra, it would make me 2X more happy.
So, here are some questions:
  1. How would i know if my Electra comes with the heavier crank or the lighter crank?
  2. If it is the lighter crank, is it possible to change this to a heavier crank?
  3. How do i make the thump from my Bullet more louder? When i say louder, i mean meaty and bassier and not crassy!
  4. Would a gold-star silencer from Sans/Pune help?
I've seen some electras with the old short-bottle silencer connected using the old bent pipe with a big fat mud-flap (some tiger ones too ). That is exactly the sound i would love to hear from my bullet. All the Bullet Gurus, could you please help?

I shall wait for your feedback/suggestions.
Thanks a lot.
Cheers,
Deepak

Last edited by starter : 23rd October 2010 at 01:01.
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Old 24th October 2010, 09:29   #178
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Quote:
Originally Posted by starter View Post
How would i know if my Electra comes with the heavier crank or the lighter crank?
  1. If it is the lighter crank, is it possible to change this to a heavier crank?
  2. How do i make the thump from my Bullet more louder? When i say louder, i mean meaty and bassier and not crassy!
  3. Would a gold-star silencer from Sans/Pune help?
I've seen some electras with the old short-bottle silencer connected using the old bent pipe with a big fat mud-flap (some tiger ones too ). That is exactly the sound i would love to hear from my bullet. All the Bullet Gurus, could you please help?

I shall wait for your feedback/suggestions.
Thanks a lot.
Cheers,
Deepak
I am not a Bullet guru, but know the answers for your questions. Here they are

1. Your bike is with lighter crank and why do you want to change it??

2. If you are looking for performance gain, then the scenario changes.

3. I believe you are only looking for meater sound, go with the short bottle of the old bullet exhaust, that will do the trick for you. My friend has it on her Machishmo, nice exhaust note.
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Old 25th October 2010, 14:44   #179
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Quote:
Originally Posted by starter View Post
  1. How do i make the thump from my Bullet more louder? When i say louder, i mean meaty and bassier and not crassy!
  2. Would a gold-star silencer from Sans/Pune help?
I've seen some electras with the old short-bottle silencer connected using the old bent pipe with a big fat mud-flap (some tiger ones too ). That is exactly the sound i would love to hear from my bullet. All the Bullet Gurus, could you please help?

I shall wait for your feedback/suggestions.
Thanks a lot.
Cheers,
Deepak

Changing the bent pipe to the one of a std 350 would definitely be able to give you a meatier thump which can be compared to the likes of the std's of the 70s-80s.
If you are not so bent upon changing the bent pipe, go for a short bottle silencer and that would make the thump a bit more bassier.
Putting in a gold star is also an option and with appropriate amount of glasswool used, the exhaust note you would get would be sweet.

I have a Machismo LB and I went for a short bottle silencer when I wanted to increase the bike's thump and was not personally happy with it. I was neither too bent towards changing the bent pipe so went for a goldstar and o'boy, I just love the exhaust note of my bull now.
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Old 2nd November 2010, 16:44   #180
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Guys

I am thinking of changing the silencer on my 2002 Thunderbird. After reading the thread i guess i have only two options Indore and Goldie. I talked to my mechanic he said the bend pipe has to be changed for Indore silencer.

Is it possible to install Indore silencer without changing the bend pipe?. As i have seen that the aftermarket bend pipe loses chrome after sometime.

What are the prices of both the silencers?

Can i ask the shopkeeper to give me a demo of the silencer before installing? I would like to see the difference between the two.

What are the disadvantages? As i noticed in the thread that it is not good for exhaust valves but my mechanic denies that.
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