November 29th, 2015, 06:46 PM | #1 |
ninjette.org member
Name: Mauricio
Location: Mexico City
Join Date: Aug 2015 Motorcycle(s): 250R Posts: 84
|
TOO Loud DanMoto GP Carbon
Hello Everyone!!
Another question after the plugs one... I have a DanMoto exhaust for my 250R but it is too loud for me. I like the tone but the volume is too high even with the baffle in the inlet side of the exhaust. My questions are: 1. Why is the baffle installed on the inlet side?? All aftermarket exhaust use this on the outlet 2. Is there a way to reduce the noise level to some thing between OEM and DanMoto?? 3. Could I modify the baffle to reduce even more the sound?? 4. What is the double wall on the baffle for?? I'n trying to understand how this baffle but not sure what to do. I know loudness is what most riders like from DanMoto but it is too much for me and my neighbours. Thanks in advance!!! I love this bike and really appreciate all the help in this forum. |
|
November 30th, 2015, 08:29 AM | #2 |
Freedom for Germany
Location: This World
Join Date: May 2011 Motorcycle(s): Ninja 250R-FI Posts: A lot.
|
Hola Mauricio,
from what I think your point no. 3 is the best idea, just modify the baffle like the Leovince DB-Eater 32BF in the attached picture. Idk how the baffle from Dan Moto looks like, but guess it is fully open? Good luck Last futzed with by Somchai; January 23rd, 2016 at 11:38 PM. |
|
November 30th, 2015, 10:12 AM | #3 |
Cat herder
Name: Gort
Location: A secret lair which, being secret, has an undisclosed location
Join Date: May 2009 Motorcycle(s): Aprilia RS660 Posts: A lot.
Blog Entries: 6
MOTM - Jul '18, Nov '16, Aug '14, May '13
|
There's a product called the DB Dawg. No experience with this:
http://www.dirtwerkz.com/mm5/merchan...egory_Code=260 Basically it's an insert you shove into the end of your pipe. It's held in with set screws, so you can take it out pretty easily. You'll need the one suitable for your pipe inner diameter. I might have to buy one of these things... I picked up a track bike at the end of last season and it has an aftermarket exhaust. Not truly obnoxious, but the noise level might be marginal for one of the tracks I ride.
__________________________________________________
I am NOT an adrenaline junkie, I'm a skill junkie. - csmith12 Nam et ipsa scientia potestas est. Heri historia. Cras mysterium. Hodie donum est. Carpe diem. |
|
December 1st, 2015, 09:39 AM | #4 |
ninjette.org guru
Name: David
Location: Knoxville, TN
Join Date: Mar 2015 Motorcycle(s): 14 Ninja 300 (Track Only), 07 CRF150RB Posts: 281
|
Following...
Planning on picking one of these slip ons up just because of the price point and the weight savings over the stock can. |
|
December 1st, 2015, 04:43 PM | #5 |
ninjette.org member
Name: Mauricio
Location: Mexico City
Join Date: Aug 2015 Motorcycle(s): 250R Posts: 84
|
I'm currently working on the baffle mod to see if this helps. As soon as I have a result I'll let you know.
|
|
December 1st, 2015, 05:05 PM | #6 |
RIP Alex
Name: Cuong
Location: Houston, TX
Join Date: Apr 2011 Motorcycle(s): '10 250r, '09 265r Posts: A lot.
Blog Entries: 2
|
best bet is to extend the baffle tube and wrap it with fiberglass.
__________________________________________________
HalfFast Racing Team Serving Greater Houston Area Riders:WFO Riders MotoHouston HPC CMRA Ride Smart Fastline Lone Star Track Days |
|
December 1st, 2015, 09:33 PM | #7 |
ninjette.org member
Name: Mauricio
Location: Mexico City
Join Date: Aug 2015 Motorcycle(s): 250R Posts: 84
|
This is what I have done so far...
Now the baffle could be inserted in the outlet side without causing any damage. I working on how to fix it there. If this does not work the next options would be: 1. Remove the double wall (the one I have cutted) 2. Cover the tube with a copper one with smaller holes 3. Replace the inner tube with a larger one with smaller holes cuong-nutz: 1. should the fiberglass be between the baffle and the perforated tube in the exhaust can?? 2. How long should the tube be?? 3. Any suggestion about the holes size?? I'm thinking on 1/4" Thanks again to all |
|
December 18th, 2015, 08:02 PM | #8 |
ninjette.org member
Name: Mauricio
Location: Mexico City
Join Date: Aug 2015 Motorcycle(s): 250R Posts: 84
|
Today I was finally able to try the slip-on with the baffle in the outlet side...
It didn't work, still too loud. Should smaller holes reduce the dB??? Measured with an iPhone app the stock exhaust generates 90dB @5000rpm meanwhile DanMoto does 120dB!!!!! Any suggestions?? |
|
December 18th, 2015, 08:43 PM | #9 |
Knee Scraper
Name: Ted
Location: King, NC
Join Date: Aug 2015 Motorcycle(s): Ninja 300 Posts: 28
|
Exhaust systems are mostly tubes that contain sound waves. (The waves produced by the pulsing of the engine combustion.)
The exhaust "muffler" works to muffle the sound by forcing it to slow down and expand before it can exit. The stock system does this with physical interruptions to the path, forcing the gases to pass through restrictive porting (the small holes) and/or sound-absorbing fiberglass matting. (FWIW, the fiberglass is simply a non-combustible material...steel wool would do the same if equal density, but steel is prone to rust, so....) If you want to restore the sound deadening to your muffler, I'd recommend a restrictor that turned the end of the muffler into a solid tube that extended into the muffler a ways, with NO HOLES, forcing the gasses around it to enter turbulent flow and interfere with the gases allowed to pass "straight through" at the narrower diameter. A longer slip on would be quieter, as would one with less direct passage of gasses, as would more dense packing (to a degree....past a point, it's WORSE, acting like a straight pipe once it's all packed in and clogged.) YMMV. Hope that helps. Think about what the gas is trying to do and hinder its' progress.
__________________________________________________
2014 Kawasaki Ninja 300 / Previous: 2013 Honda CBR500R - RIP, 2003 Suzuki SV650 / 2013 Honda CBR250R / 2003 Suzuki GZ-250 |
|
December 20th, 2015, 08:11 PM | #10 |
Certifiable nontundrum
Name: Harper
Location: NC Milkshake stand
Join Date: Mar 2013 Motorcycle(s): 2013 SE NINJA 300 Posts: Too much.
MOTM - Sep '13, Sep '16
|
They making dildos for moto exhaust systems now
__________________________________________________
|
|
December 28th, 2015, 08:24 AM | #11 |
ninjette.org guru
Name: David
Location: Knoxville, TN
Join Date: Mar 2015 Motorcycle(s): 14 Ninja 300 (Track Only), 07 CRF150RB Posts: 281
|
|
1 out of 1 members found this post helpful. |
December 30th, 2015, 01:22 PM | #12 |
ninjette.org member
Name: Mauricio
Location: Mexico City
Join Date: Aug 2015 Motorcycle(s): 250R Posts: 84
|
Yes Thanks, but it was too late for me... As I live in Mexico I have to order trough the international site where the parts are cheaper but the shiping is really expensive.
I paid 86 for the Carbon GP and another 86 for shipping, so order a new one is not an option. I keep trying to modify the baffle with no results so far I'll keep you informed |
|
December 30th, 2015, 02:51 PM | #13 |
ninjette.org guru
Name: David
Location: Knoxville, TN
Join Date: Mar 2015 Motorcycle(s): 14 Ninja 300 (Track Only), 07 CRF150RB Posts: 281
|
I can only imagine how loud my bike is gonna be. I got the same exhaust but it didnt come with a baffle. If its too much then ill order one but hope i dont have to.
|
|
December 30th, 2015, 03:39 PM | #14 | |
Daily Ninjette rider
Name: Hernan
Location: Florida
Join Date: Mar 2011 Motorcycle(s): 2007 Ninja 250 Posts: A lot.
MOTY - 2016, MOTM - Dec '12, Jan '14, Jan '15, May '16
|
Quote:
You paid for a straight passage to exhaust gases with some attempt for attenuation of noise by absorption. The excessive noise comes from the disturbance of the atmosphere that the sudden successive expansions of those gases going from high pressure (several atmospheres) to zero atm and subsequent speed produce. Those are high pressure/speed pulses in the gas (high energy) that reach ears via the atmosphere. The manufacturers use several methods of noise (energy) attenuation: 1) Using baffles and internal passages and tubes, they divert the flow back and forth and then make the pulses of one interfere with the pulses of the other (a + peak overlaps a - peak, resulting in close to zero pressure. Your DanMoto does not do that: it is a simple straight shoot. Installing internal baffles and tubes and experimenting with the location of those could help you. The main problem would be anchoring those things to the carbon-fiber shell. 2) The OEM mufflers also try cooling the exhaust gases between inlet and outlet, achieving less volume to be discharged, which equals reduced disturbance. They do that using big shinning surfaces exposed to the air stream and keeping the gases moving back and forth within those surfaces. Your exhaust gases reach the atmosphere hotter and occupying more volume. 3) They sometimes try creating noise absorbing internal walls with soft materials protected by some mesh or perforated sheets. That works for the gases hitting those walls at relatively low speed, but does nothing for the gases that move faster by the center of the pipe. That material tends to get burned and blown away, and needs periodic re-packing. I believe that is the purpose of the double wall on the baffle of your DanMoto, which is doing some attenuation (if in good condition), but not enough for you.
__________________________________________________
Motofool .................................Never ride faster than your guardian angel can fly "Mankind is composed of two sorts of men — those who love and create, and those who hate and destroy. Love is the bond between men, the way to teach and the center of the world." - José Martí |
|
|
December 30th, 2015, 04:56 PM | #15 |
ninjette.org member
Name: Mauricio
Location: Mexico City
Join Date: Aug 2015 Motorcycle(s): 250R Posts: 84
|
Thanks Motofool!!
Attached is the photo of the DanMoto baffle without the double wall and the cap... If I understand correctly using a longer tube with smaller holes in two sections might help. Now that I removed the double wall I think it was there to protect the carbon fibre from the heat... |
|
December 30th, 2015, 08:00 PM | #16 | |
Private Joker
Name: Ben
Location: Towson, MD
Join Date: Nov 2012 Motorcycle(s): '99/'01 Ninja 250 "sketchy", '13 Ninja 300 "yoshi", '03 GSXR 600 "merlin" Posts: A lot.
MOTM - Mar '14
|
Quote:
__________________________________________________
I see you over there seeing me, do you see the me I think you see? |
|
|
December 30th, 2015, 08:40 PM | #17 | |
Daily Ninjette rider
Name: Hernan
Location: Florida
Join Date: Mar 2011 Motorcycle(s): 2007 Ninja 250 Posts: A lot.
MOTY - 2016, MOTM - Dec '12, Jan '14, Jan '15, May '16
|
Quote:
It may help, as long as is not aligned with the exhaust pipe. Try thinking like you were the exhaust gases traveling the easiest path between high and low pressure. Would you go through those holes on the wall or through the center of the main tube? The attached schematic belongs to real Yamaha engines. Notice how the flow is forced to follow a path with successive expansions. Yes, heat and epoxy resin don't get alone.
__________________________________________________
Motofool .................................Never ride faster than your guardian angel can fly "Mankind is composed of two sorts of men — those who love and create, and those who hate and destroy. Love is the bond between men, the way to teach and the center of the world." - José Martí |
|
|
December 31st, 2015, 05:02 AM | #18 |
ninjette.org guru
Name: David
Location: Knoxville, TN
Join Date: Mar 2015 Motorcycle(s): 14 Ninja 300 (Track Only), 07 CRF150RB Posts: 281
|
Looks like ill just be getting used to riding with hearing protection on haha.
|
|
December 31st, 2015, 03:23 PM | #19 |
ninjette.org member
Name: Mauricio
Location: Mexico City
Join Date: Aug 2015 Motorcycle(s): 250R Posts: 84
|
Finally the modification to the DanMoto baffle is done.
Using Motofool advice and some images from internet I made a baffle. It all started with a 1", thin wall copper tube. Some cuts, a hammer and a drill helped me to finish a baffle which I hope can reduce the dB my DanMoto creates. attached are some images of the process. Maybe tomorrow I'll try it. Thanks to all and have a happy new year!!!! |
1 out of 1 members found this post helpful. |
January 1st, 2016, 06:12 PM | #20 |
ninjette.org member
Name: Mauricio
Location: Mexico City
Join Date: Aug 2015 Motorcycle(s): 250R Posts: 84
|
It DID work!!!!
Sound level is lower but the tone is great!!!. Maybe I'll try with some Steel Wool or exhaust packing to see what happens, but is already a lot better. Thanks to all!!! |
|
January 3rd, 2016, 09:46 PM | #21 | |
Daily Ninjette rider
Name: Hernan
Location: Florida
Join Date: Mar 2011 Motorcycle(s): 2007 Ninja 250 Posts: A lot.
MOTY - 2016, MOTM - Dec '12, Jan '14, Jan '15, May '16
|
Quote:
Copper may break soon, ....maybe not. That material tends to develop cracks when stressed by temperature changes and vibrations. Now exhaust sounds and noises are not a mystery anymore. You are welcome
__________________________________________________
Motofool .................................Never ride faster than your guardian angel can fly "Mankind is composed of two sorts of men — those who love and create, and those who hate and destroy. Love is the bond between men, the way to teach and the center of the world." - José Martí |
|
|
January 4th, 2016, 09:04 AM | #22 |
ninjette.org guru
Name: David
Location: Knoxville, TN
Join Date: Mar 2015 Motorcycle(s): 14 Ninja 300 (Track Only), 07 CRF150RB Posts: 281
|
But now with this baffle in there would you need to rejet?
|
|
January 4th, 2016, 08:38 PM | #23 |
ninjette.org member
Name: Mauricio
Location: Mexico City
Join Date: Aug 2015 Motorcycle(s): 250R Posts: 84
|
|
|
July 11th, 2018, 02:55 PM | #24 |
ninjette.org newbie
Name: Kai
Location: Vancouver
Join Date: Jul 2018 Motorcycle(s): cbr250r Posts: 1
|
steel wool will definitely help. maybe put it in the mid pipe to prevent it from blowing out.
|
|
July 13th, 2018, 06:48 AM | #25 |
????????????????
Name: T
Location: no where
Join Date: Feb 2016 Motorcycle(s): 2007 ninja 250, 14 ninja 300, 09 1125CR Posts: A lot.
MOTM - May '17
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
DanMoto Carbon full system | jasle | Motorcycle-related | 2 | November 28th, 2012 05:08 PM |
Help!! Installation of Danmoto Carbon Slip-on | Shark | 2008 - 2012 Ninja 250R Farkles | 3 | October 2nd, 2012 07:11 PM |
Danmoto Carbon GP Doesn't Seem Secured | Francis | 2008 - 2012 Ninja 250R Tech Talk | 5 | June 16th, 2012 03:19 PM |
Looking to trade my danmoto carbon gp exhaust for a jisu | NinjaBoyEddy | Items Wanted | 1 | April 30th, 2012 10:54 PM |
DanMoto Carbon Questions! | Armo55 | 2008 - 2012 Ninja 250R Tech Talk | 3 | March 16th, 2012 08:55 PM |
|
|