Need Advice regarding exhaust
08-01-2013, 04:37 AM
#1
Junior Member
Squid
Thread Starter
Join Date: Sep 2010
Posts: 6
Need Advice regarding exhaust
Hello Guys, I need your opinion on what I am about to do with my bike
I ride a 1999-2000 Honda VTR Firestorm 1000f, I got it stock and one of the first things we did was to open up the exhaust by changing the tip, Basically to let it breath and make a bit of noise. I have been using it for some time already but I did notice that the top end was not so powerful anymore (maybe just my imagination) but some friends say that the exhaust is too big. What do you think?
Anyway, I am planning to remove the Dual exhaust replacing it with a single carbon yoshimura exhaust from another liter bike (gsxr1000). Some friends say that it will run better some say it won’t have much breathing space.
Seeking for your personal expert advice
Thanks!
I ride a 1999-2000 Honda VTR Firestorm 1000f, I got it stock and one of the first things we did was to open up the exhaust by changing the tip, Basically to let it breath and make a bit of noise. I have been using it for some time already but I did notice that the top end was not so powerful anymore (maybe just my imagination) but some friends say that the exhaust is too big. What do you think?
Anyway, I am planning to remove the Dual exhaust replacing it with a single carbon yoshimura exhaust from another liter bike (gsxr1000). Some friends say that it will run better some say it won’t have much breathing space.
Seeking for your personal expert advice
Thanks!
08-01-2013, 06:55 AM
#3
Senior Member
SuperBike
Join Date: Jul 2011
Location: South of Live Free or Die & North of Family Guy
Posts: 1,456
There are different schools of thought, but I would suggest go to the following thread and you will find allot of good info to work with and make your call on what to do:
https://www.superhawkforum.com/forum...-setups-28999/
https://www.superhawkforum.com/forum...-setups-28999/
08-01-2013, 06:58 AM
#4
Senior Member
SuperSport
Join Date: Oct 2012
Location: Orlando, FL
Posts: 501
Hello Guys, I need your opinion on what I am about to do with my bike
I ride a 1999-2000 Honda VTR Firestorm 1000f, I got it stock and one of the first things we did was to open up the exhaust by changing the tip, Basically to let it breath and make a bit of noise. I have been using it for some time already but I did notice that the top end was not so powerful anymore (maybe just my imagination) but some friends say that the exhaust is too big. What do you think?
Anyway, I am planning to remove the Dual exhaust replacing it with a single carbon yoshimura exhaust from another liter bike (gsxr1000). Some friends say that it will run better some say it won’t have much breathing space.
Seeking for your personal expert advice
Thanks!
I ride a 1999-2000 Honda VTR Firestorm 1000f, I got it stock and one of the first things we did was to open up the exhaust by changing the tip, Basically to let it breath and make a bit of noise. I have been using it for some time already but I did notice that the top end was not so powerful anymore (maybe just my imagination) but some friends say that the exhaust is too big. What do you think?
Anyway, I am planning to remove the Dual exhaust replacing it with a single carbon yoshimura exhaust from another liter bike (gsxr1000). Some friends say that it will run better some say it won’t have much breathing space.
Seeking for your personal expert advice
Thanks!
Usually if you go to open on the exhaust you end up with lower top end power due to decreased back pressure, same reason stunters, and I4 guys cut their pipes in half and rerivet them, gives more on the low end while taking away from the top.
It is possible to go to a single exhaust but its not easy and involves a lot more than just capping the exhaust and running 1 slip on. To get the bike to perform any where close to decent it will take a lot to trial and error tuning and good knowledge of exhaust flow and these carborators.
These bikes have poor exhaust flow from the factory, not the worst but not the best either, IMHO it is best to stick with dual exhaust and find a pair of slip ons to satisfy your craving for better sound. Proper back pressure is needed for any engine to run correctly, Hawks especially.
And remember this is just my $.02
08-01-2013, 04:24 PM
#5
Senior Member
Superstock
Join Date: May 2012
Location: UK
Posts: 397
Usually if you go to open on the exhaust you end up with lower top end power due to decreased back pressure
(:-})
08-01-2013, 04:27 PM
#6
Senior Member
Superstock
Join Date: Oct 2011
Posts: 344
backpressure doesn't generate power, exhaust gas speed does, there's tons of articles out there...but basically some Honda engineer spent a long time developing the stock exhaust shape, so unless you fancy yourself a gas flow specialist it may not be worth it to go to a 2 into 1 setup.
I did, and it was massively annoying getting the thing to run right...I only did it because one side of my exhaust got rusted and ruined (unsure how, it was like that when I got it).
I did, and it was massively annoying getting the thing to run right...I only did it because one side of my exhaust got rusted and ruined (unsure how, it was like that when I got it).
08-01-2013, 04:45 PM
#7
Senior Member
Superstock
Join Date: May 2012
Location: UK
Posts: 397
Indeed it's a lot more complicated than just pressure but it's the velocity of the flow and the control of scavenging from the pulses as things change from a positive to negative pressure. The exhausts are a highly tuned length and when you start changing things you getting into an unknown territory and it could boil down to trial and error along with jetting to suit. It's a bit like porting heads, it's not always beneficial to open things up, yes you get more but it slows the velocity. Gas flow and fluid dynamics I think are closely related and highly specialist tools and knowledge are required. A very interesting area to read about but a bit of a Black art.
(:-})
(:-})
08-01-2013, 07:29 PM
#8
Senior Member
SuperSport
Join Date: Apr 2013
Posts: 972
I agree, everything is tuned from the airbox to the tip of the exhaust, together. Pretty damn well! Honda knows many will add slip-ons and I believe factor this in re main jets. Two large pistons = large exhaust pulses. Thats why there are two huge cans on these bikes, so package can be tuned properly.
Last edited by jerryh; 08-01-2013 at 07:32 PM.
08-01-2013, 10:37 PM
#9
Senior Member
MotoGP
Join Date: Jul 2007
Location: NYC
Posts: 5,033
I have 2 vtrs, one 2 into 1 devil carbon, one two brothers dual slip ons. I like everything about the 2 cans better. Throttle response, sound, etc. I think its way easier to tune duals since I have spent alot of time tuning both.
The 2bros are actually high mounts that I converted to low mount to accomodate the givi rack. Doest like as trick but funtions way better.
The 2bros are actually high mounts that I converted to low mount to accomodate the givi rack. Doest like as trick but funtions way better.
08-02-2013, 05:14 AM
#10
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MotoGP
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Location: Gettysburg, Pa
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