Author |
Message |
D_adams
| Posted on Thursday, December 02, 2010 - 06:52 am: |
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Is it enough? At idle, Al's testing showed most of the aftermarket pipes were 98-99 db at idle. I've been playing with some perforated tube to see if I can make a difference on sound. My overly critical sound department (ie; the wife) says it's definitely not as loud since it's not shaking the walls in the house when I start it up. This was with the garage door shut last night. Sound readings showed 94-95 db at idle, but I'm not 100% sure of the accuracy of the recorder. |
Redbuell1203
| Posted on Thursday, December 02, 2010 - 07:34 am: |
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A 4-5 db drop would be nice for an insert that is removable. I just like a little noise now and then. Keep up the great work. |
D_adams
| Posted on Thursday, December 02, 2010 - 08:05 am: |
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It is a removable insert. Takes a couple of minutes to install one and have the pipe back on the bike. |
Jdugger
| Posted on Thursday, December 02, 2010 - 08:07 am: |
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Go get a decent DB meter. $250 or less for one that's calibrated and would do a good job. Generally sound level is measured at one meter. |
Red93stang
| Posted on Thursday, December 02, 2010 - 08:12 am: |
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I like ur work Dean and I will like it even more if the db's come down! Good work! |
Dannybuell
| Posted on Thursday, December 02, 2010 - 09:16 am: |
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Sounds like you are on the right track. will this tube be stainless as well? |
D_adams
| Posted on Thursday, December 02, 2010 - 09:40 am: |
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I always use stainless whenever possible. The exceptions are fasteners (nuts & bolts) and rubber grommets. |
Ratsmc
| Posted on Thursday, December 02, 2010 - 12:36 pm: |
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4-5db is going to be relative to the starting level since db as a measurement increases at a logarithmic rather than linear rate. a 5db increase from 100db is going to be a lot more sound force than a 5 db increase from 60db. |
Duphuckincati
| Posted on Thursday, December 02, 2010 - 01:21 pm: |
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What's the reading with the stock pipe? The main appeal to me for an aftermarket pipe is looks, weight loss and a better but not too loud sound. Build your twin-pipe unit with a quiet(er) insert and I'm there. I've got a loud bike when in the mood. (beater 900SS Duc with J.C. Whitney $52.00 Dunstall replicas!) (goggle "Du*uckincati" with an "f") |
Maximum
| Posted on Thursday, December 02, 2010 - 01:43 pm: |
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Stock = 88 db at idle |
Bob_thompson
| Posted on Thursday, December 02, 2010 - 06:32 pm: |
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I believe you're on the right track Dean. I've been using a perforated cone insert for five years now on my straight through packed muffler systems with great results. First on my M2 and now on my 1125R. One note I have found is the longer the insert is the quieter it is and a side benefit is less restriction due to more perforated holes and greater flow. I calculated the hole sizes and cross section area of the openings to have more hole area then the cross section of the 2 1/4" pipe I am using and why I had to go longer so as to not reduce flow. IT DOES WORK. Period. Hint: face the cone pointing toward the head and definitely use a tuning device, especially Erik Buell Racing's race ECM. Sound reduction and flow with proven performance. Win/win for very little cost. Proven on metro drag strips all over the country where noise restrictions apply, even on open headers. Good luck my friend, you have, in my opinion the best performing and looking pipes available for our Buells. Bob |
Father_of_an_era
| Posted on Thursday, December 02, 2010 - 09:48 pm: |
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"you have, in my opinion the best performing and looking pipes available for our Buells. Bob" \black) 100% agree!! |
D_adams
| Posted on Thursday, December 02, 2010 - 10:20 pm: |
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The one I made is kinda like the symbol for an atom. It seems to be somewhat effective for noise reduction but also has sufficient flow through to not restrict the actual volume in movement. The tone is still the same, it's just a little lower in noise/volume. Make sense? The surface area is four 1/2" strips of perforated material. It almost looks like a ball. I still need to actually road test it, but it's been in the 20's in the mornings, so I've kinda wimped out on test riding it.
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Crazyhawk99
| Posted on Friday, December 03, 2010 - 06:36 am: |
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Dean, Kudos on the work you are doing. I have always been interested in your exhaust, but put off by the level of sound output. Keep us posted! |