Hey all,
Wondering if anyone has an oppinion, suggestion or solution to what I've observed in the last few days riding.
I have made a drastic exhaust change on my 93.
I went from a stock system to a full two brothers left hand exit system. I've then shorten the TBR silencer by about 6 inches. It sounds crazy!!!
but I've noticed that it does pop on downshifting and engine breaking and the bike seems a bit more rumbly (noticably vibrating to the tune of the exhaust) overall.
I haven't altered anything in the air box department - altho was considering a K&N filter upgrade - nor did I re-jet the carbs.
Do you guys think that this is just a product of a too short of a silencer, or a combination of things - and more importantly - am I running the risk of damaging my baby??
If anyone has a suggestion, solution - so forth - please let me know.
Its called "Lean pop"
You have more air than fuel in there. A re-jetting will do wonders, with the added benift(besides running correctly) of that fat, slightly rich sound. sounds like velvet.
we can get away with these shananigans on later bikes because of fuel injection. right now your carbs hate you. (as does your exhaust valves)
http://www.pjsparts.com/catalog/images/7%20-%20Fun%20Stuff/T-Shirt%201%20Back%20PJ%202.jpg
Just sayin'...
Oh... And...
http://www.delorey.com/client/images/lpsl_2009-08-24.jpg
It's probably lean like Timmy mentioned but before you tear in to the carbs double check all the exhaust system connection points and the connections to the heads to make sure you're not sucking air in anywhere.
I can't remember if the 3gen has PAIR but if so that is also a source of lean firing on trailing throttle as it burns unspent gas.
[image: View Post]FotoMoto, on 14 June 2010 - 01:24 PM, said:
I can't remember if the 3gen has PAIR but if so that is also a source of lean firing on trailing throttle as it burns unspent gas.
+1
Rejet that sucker
I AM DEAF!! HOW THE F@&% DO I KNOW?????? :pissed:
:laughing6-hehe:
just messing with ya!
remove the pair set up and block off the pair holes.
rejet the carbs..get a k&n filter :fing02:
[image: View Post]vfrcapn, on 14 June 2010 - 01:07 PM, said:
It's probably lean like Timmy mentioned but before you tear in to the carbs double check all the exhaust system connection points and the connections to the heads to make sure you're not sucking air in anywhere.
+1....
Ive also binned the snorkel after adding a K&N to my air box......
Cant wait to cut my 2bros system down to a GP style shorty style pipe.....im assuming i will definitely benefit from a Dyno-jet after binning the end can.
Ok,
Going to re-check the header connections - but pretty sure they should be pretty much perfect. Lined up great and with new exhaust gaskets. But will re-check that whole setup. If need be, will remove the body again and re-check the fit...
But, if that doesn't help, then it sounds like a re-jet is the only thing that will work. I'm not sure I know enough about that to do it myself.
Anyone have a guy or are there guru's on here who do this?? Is this something a shop can do? Or dealer exclusive? Or is it something that has to be done by someone who simply knows the right combination dependent on the variables... Either way - I'm pretty sure that in all those cases the person doing this - isn't likely me...
What do I do? Is the wise thing to do, to put the stock back on? Is this going to damage the bike in any detrimental fashion if I ride like that for a summer??
Any thoughts?
[image: View Post]Paper, on 14 June 2010 - 01:00 PM, said:
http://www.pjsparts.com/catalog/images/7%20-%20Fun%20Stuff/T-Shirt%201%20Back%20PJ%202.jpg
Just sayin'...
Oh... And...
http://www.delorey.com/client/images/lpsl_2009-08-24.jpg
Whoa, slow it down there buck!
Feelin pretty strong about the loud pipe issue, eh?
Well, since you're not really contributing to this thread in technical manner - I'm going to kindly disregard your input.
AND as someone who got run off the road, and into a really scary situation, I beg to differ with the claim that loud pipes don't save lives. They sure as hell make others aware of you - we ride our bike, watch the road, watch the traffic, leave room in our judgment to account for other drivers mistakes on the road - but not even the best of us can predict what some nimrods behind a wheel will do. I added a few db's for those morons.
cheers!
Please quit crying about the loud pipes,are they ever really that loud?straight piped HD & Choppers (YES) but the sweet sound of the V4 BRING IT ON!
781 EDGES.
a great way to see if the exhaust pipes are seated right..
borrow a cancer stick from someone.. and wave it around the area.. the leak will blow the smoke away. :fing02:
LOUD pipes save lives??
before or after a deaf guy runs them over? :laughing6-hehe: :laughing6-hehe:
What you are hearing is a popping resonating sound generated by a lean
condition on decel. When you suddenly close the throttle, the incoming
air is choked off and the closed throttle also causes the bike to
return to idle on the very lean idle circuit of the carbs. However,
momentum of the bike is actually "driving" the engine in a sense, and
that engine is still spinning at rpm that needs far more gas than the
closed throttle/carb can provide. The engine is still spinning but the
incoming fuel rate is very low, until just enough builds up in the
combustion chamber to "fire" on the exhaust stroke of the engine.
Modifying the exhaust (especially if it gets louder) will only make it
worse, and louder when it pops. Because most aftermarket pipes produce
"lower back pressure", it makes matters worse yet because lower back
pressure pipes actually cause the fuel/air mix to LEAN OUT EVEN MORE.
The solution is in the carbs, and it requires a richer fuel/air
mixture. The only logical way to do that is to get a Dynojet or K&N
brand "jet kit" installed.
[image: View Post]vfrgo, on 14 June 2010 - 11:03 PM, said:
Ok,
Is this going to damage the bike in any detrimental fashion if I ride like that for a summer??
Any thoughts?
I also would like to know if this would cause damage to the engine. I have more of a low "burble" sound on decel than a popping.
[image: View Post]vfrgo, on 15 June 2010 - 07:20 PM, said:
Whoa, slow it down there buck!
Feelin pretty strong about the loud pipe issue, eh?
Well, since you're not really contributing to this thread in technical manner - I'm going to kindly disregard your input.
AND as someone who got run off the road, and into a really scary situation, I beg to differ with the claim that loud pipes don't save lives. They sure as hell make others aware of you - we ride our bike, watch the road, watch the traffic, leave room in our judgment to account for other drivers mistakes on the road - but not even the best of us can predict what some nimrods behind a wheel will do. I added a few db's for those morons.
cheers!
Quoting me in a reply is hardly disregarding my input..
And yeah, I'm pointing more towards the HD Pirate crowd with the noise issue, but..
As far as contributing in a technical manner, I didn't see that in the rules when I joined.. The title to this topic is
Is my Two Brothers on a 93 too loud?? and if you have to ask that question, the answer is more than likely, YES!! (see, that's loud, too) :musik20:
My 1996 came with a Yoshi pipe and I put a Dekevic on it to quiet it down.. My other bikes have stock exhaust and they're quiet.. I'm not bothering my neighbors, people I pass on the highway, small children,
or people who vote against motorcycles because they're too DAMNED LOUD!!
And you can place the blame on being run off the road because someone in a car with the radio on didn't hear you.. I'd bet a shiny new nickle that if you had made sure they saw you in some other manner than hearing, chances are you might not have been run off the road..
Huh? I have a hard enough time hearing, and I enjoy my air conditioning and my car stereo.. I usually enjoy both of these so I don't have to listen to idiots with loud pipes.. :fing02:
I guess my point is that while even I enjoy the sound of a wound out VFR, not everyone does.. I think the sound of a straight pipe Harley to be nothing but annoying noise, but there's many out there that think it's the sound of the heavens..
Problem is, old Tom from down the street is tired of hearing you ride by on your VFR, and also the pirate down the street with the loud Harley.. In Tom's world, they're all the same and all annoying.. Problem is, Tom hangs out with Dick and Harry at McDonalds for coffee every morning, as many retired people do.. Know what else they do?? They write a LOT of letters to congressmen, telling them about the fact that they vote at every election, and that they're tired of hearing these loud motorcycles..
Congressman Doodle starts a bill to get all aftermarket exhaust banned, have all insurance benefits removed from people who ride motorcycles, and force all male motorcycle riders to have one of their nuts crushed with a pair of pliers.. :laughing6-hehe: I know.. Can't happen... But more stupid things have happened over less stupid reasons..
Loud pipes are just given them a reason for your nuts to be crushed... Yeah, I'm being funny, but only to a point... I don't want my nuts crushed, and I don't want my rights taken away..
[image: View Post]Paper, on 16 June 2010 - 10:32 PM, said:
I guess my point is that while even I enjoy the sound of a wound out VFR, not everyone does.. I think the sound of a straight pipe Harley to be nothing but annoying noise, but there's many out there that think it's the sound of the heavens..
Problem is, old Tom from down the street is tired of hearing you ride by on your VFR, and also the pirate down the street with the loud Harley.. In Tom's world, they're all the same and all annoying.. Problem is, Tom hangs out with Dick and Harry at McDonalds for coffee every morning, as many retired people do.. Know what else they do?? They write a LOT of letters to congressmen, telling them about the fact that they vote at every election, and that they're tired of hearing these loud motorcycles..
Congressman Doodle starts a bill to get all aftermarket exhaust banned, have all insurance benefits removed from people who ride motorcycles, and force all male motorcycle riders to have one of their nuts crushed with a pair of pliers.. :laughing6-hehe: I know.. Can't happen... But more stupid things have happened over less stupid reasons..
Loud pipes are just given them a reason for your nuts to be crushed... Yeah, I'm being funny, but only to a point... I don't want my nuts crushed, and I don't want my rights taken away..
Thread hijacking, like loud pipes, is rather annoying. Where do you stand on that particular topic? :huh:
Ciao,
Soooooo, getting back on topic, anyone want to chime in on the "is it doing any damage" question?
[image: View Post]gm1777, on 19 June 2010 - 11:53 AM, said:
Soooooo, getting back on topic, anyone want to chime in on the "is it doing any damage" question?
To be more specific; does anyone know if this lean decel pop damages the bike or motor in anyway?
did you pull the plug and see what color it is? if its a brown/ dark tan color.. your ok.. if its WHITE.. it MAY.. thats MAY start to break up your spark plug which leads to preignition after a while and that can mess things up.
its best to see what your plugs look like now and go from there. :fing02:
did you pull the plug and see what color it is? if its a brown/ dark tan color.. your ok.. if its WHITE.. it MAY.. thats MAY start to break up your spark plug which leads to preignition after a while and that can mess things up.
its best to see what your plugs look like now and go from there. :fing02:
[image: View Post]JZH, on 19 June 2010 - 09:56 AM, said:
Thread hijacking, like loud pipes, is rather annoying. Where do you stand on that particular topic? :huh:
Ciao,
Thread hijacking isn't illegal, doesn't cause hearing loss, or allow politicians to take away all motorcyclists rights..
Loud pipes do..
That's where I stand..
(Hey, you asked...) :fing02:
[image: View Post]Paper, on 14 June 2010 - 01:00 PM, said:
http://www.pjsparts.com/catalog/images/7%20-%20Fun%20Stuff/T-Shirt%201%20Back%20PJ%202.jpg
Just sayin'...
Oh... And...
http://www.delorey.com/client/images/lpsl_2009-08-24.jpg
Take a break. Dude. You're working way too hard.
[image: View Post]vfrgo, on 14 June 2010 - 11:03 PM, said:
Ok,
Going to re-check the header connections - but pretty sure they should be pretty much perfect. Lined up great and with new exhaust gaskets. But will re-check that whole setup. If need be, will remove the body again and re-check the fit...
But, if that doesn't help, then it sounds like a re-jet is the only thing that will work. I'm not sure I know enough about that to do it myself.
Anyone have a guy or are there guru's on here who do this?? Is this something a shop can do? Or dealer exclusive? Or is it something that has to be done by someone who simply knows the right combination dependent on the variables... Either way - I'm pretty sure that in all those cases the person doing this - isn't likely me...
What do I do? Is the wise thing to do, to put the stock back on? Is this going to damage the bike in any detrimental fashion if I ride like that for a summer??
Any thoughts?
Make sure you check the two rear short header pipes where they connect to the main header pipes. Those seals take a beating if people use their header pipes to support the bike during front wheel removals etc. Re jetting carbs and or repacking your cannister if it is a use one are your best option if no exhaust leak is found. Rejetting is worthwhile anyways if it hasn't been done to match the free flowing exhaust. May as well do the airfilter and de snork and de pair while you are in there. :fing02: That generation VFR is bomb proof. Well worth investing a little in.
[image: View Post]Paper, on 19 June 2010 - 11:26 PM, said:
[image: View Post]JZH, on 19 June 2010 - 09:56 AM, said:
Thread hijacking, like loud pipes, is rather annoying. Where do you stand on that particular topic? :huh:
Ciao,
Thread hijacking isn't illegal, doesn't cause hearing loss, or allow politicians to take away all motorcyclists rights..
Loud pipes do..
That's where I stand..
(Hey, you asked...) :fing02:
Number 1 is irrelevant, number 2 is absurd, and number 3 is, again, all about you... Please go start your own thread. :comp13:
Ciao,
Thread is about an exhaust popping condition. Perhaps an exhaust leak or engine damaging lean running condition. Two Bros. makes an excellent product but some of the older models are known to get louder due to the packing settling or deteriorating. I'd repack it if it seems excessively loud.
In Fairness the title does ask is my two bros pipe too loud? So not off topic to discuss loud pipes here as well. Putting the stock pipe back on might cure the lean condition as well.
Motorcycle rights are earned by responsible motorcyclist who show courtesy to other drivers and the public. Those couragious enough to chide an offending loud pipe running crowd are entitled to make their point but realize slightly louder than stock is not offensive.
As a daily commuter on southern california freeways and a weekend canyon rider I realize the major noise affecting a riders hearing is wind noise. Second loudest in traffic is tire roar combined with engine howl. Having worked construction building bridges on live freeways I can tell you a well tuned slightly louder than stock exhaust was a welcome relief to the cacophony of car and semi noise. Loud blatting Harley's are as offensive as Jake brakes on a semi.
Wear earplugs when you ride even if your bike is stock. Ear plugs are illegal though. Wear them anyways. Next thing you know they'll make speeding illegal too.
[image: View Post]JZH, on 20 June 2010 - 08:04 AM, said:
number 2 is absurd, and number 3 is, again, all about you...
:mellow: loud pipes dont cause hearing loss??? did you bang your head last week or something?? i dont want to call you stupid but your your clearly not using your noggin! a HUGE percentage of HD rides have hearing loss in the right ear!!!!(pipeside!!)
as for #3 "all about you" its not just about him .. its about YOU TOO if you ever ride in america ! philadelphia has limited DB level on many "main strips" like south street.. a hangout off all ages. a 10 bloc long crawl looking at babes and such.. then the law changed and now if your bike is too loud.. TICKET TIME!
so.. as for his vfr750.. i dont think it will be a screamer.. but if we ever go to jims steaks on south street... dont start blipping the throttle to watch the window rattle. :beer:
http://i164.photobucket.com/albums/u30/gll429/vfrd.jpg
its all moot when a deafie runs your butt over! :goofy:
[image: View Post]gll429, on 20 June 2010 - 05:36 PM, said:
:mellow: loud pipes dont cause hearing loss??? did you bang your head last week or something?? i dont want to call you stupid but your your clearly not using your noggin! a HUGE percentage of HD rides have hearing loss in the right ear!!!!(pipeside!!)
as for #3 "all about you" its not just about him .. its about YOU TOO if you ever ride in america ! philadelphia has limited DB level on many "main strips" like south street.. a hangout off all ages. a 10 bloc long crawl looking at babes and such.. then the law changed and now if your bike is too loud.. TICKET TIME!
I didn't know about the alleged Harley hearing issue. For most riders (which includes most of the people on this forum), their hearing will be irreparably damaged by wind noise long before any effect from loud exhausts comes into play. You may not know this, but most riders cannot even hear their own exhausts whilst riding--I certainly can't. Besides, if we're just talking about open Harley pipes, then we can move this into the "irrelevant" category in any case...
Don't believe the hype (and yes, I do sometimes ride in America). Obviously, people who like to lecture others often (perhaps without exception) cast their "words of wisdom" in terms of "you" or "us", but this affliction is almost invariably a result of some form of narcisissm. They say "our " rights might be curtailed, but they mean "my" rights might be curtailed. My exhausts are not excessively loud, and it's certainly possible that the OP's TBR is excessively loud, at least in the context of the average "loud" motorcycle exhaust, which is necessarily weighted heavily in favour of American V-Twins. Accordingly, we can lecture ourselves night and day about this and it wouldn't make one iota of difference to the Harley crowd--and make no mistake, that's what will lie behind any sort of legislative or law enforcement solution. As a result, any lectures given here are essentially wasted effort, but if someone really wants to satisfy that particular urge, they should start their own thread. (IMHO.)
Ciao,
[image: View Post]BusyLittleShop, on 16 June 2010 - 02:57 AM, said:
What you are hearing is a popping resonating sound generated by a lean
condition on decel. When you suddenly close the throttle, the incoming
air is choked off and the closed throttle also causes the bike to
return to idle on the very lean idle circuit of the carbs. However,
momentum of the bike is actually "driving" the engine in a sense, and
that engine is still spinning at rpm that needs far more gas than the
closed throttle/carb can provide. The engine is still spinning but the
incoming fuel rate is very low, until just enough builds up in the
combustion chamber to "fire" on the exhaust stroke of the engine.
Modifying the exhaust (especially if it gets louder) will only make it
worse, and louder when it pops. Because most aftermarket pipes produce
"lower back pressure", it makes matters worse yet because lower back
pressure pipes actually cause the fuel/air mix to LEAN OUT EVEN MORE.
The solution is in the carbs, and it requires a richer fuel/air
mixture. The only logical way to do that is to get a Dynojet or K&N
brand "jet kit" installed.
How does this work with FI? My Tbros full exhaust used to pop a lot on engine decel, especially right around 3K rpm. I had an appropriate fuel map loaded to my PC2 for the exhaust and K&N.
I've now re-installed the stock exhuast and canister and loaded a standard map, stock exhaust w/ K&N, but I'm still getting the annoying pop on engine decel around 3K rpm. As far as I can tell I don't have any exhaust leaks like I did with the TBros. Any tips on fixing this up? Add more fuel to the map around 0 throttle/3K rpm? Go back to the oem a/f mapping? Would exhaust valves way out of spec contribute to this?
[image: View Post]vfrgo, on 14 June 2010 - 12:35 PM, said:
Hey all,
Wondering if anyone has an oppinion, suggestion or solution to what I've observed in the last few days riding.
I have made a drastic exhaust change on my 93.
I went from a stock system to a full two brothers left hand exit system. I've then shorten the TBR silencer by about 6 inches. It sounds crazy!!!
but I've noticed that it does pop on downshifting and engine breaking and the bike seems a bit more rumbly (noticably vibrating to the tune of the exhaust) overall.
I haven't altered anything in the air box department - altho was considering a K&N filter upgrade - nor did I re-jet the carbs.
Do you guys think that this is just a product of a too short of a silencer, or a combination of things - and more importantly - am I running the risk of damaging my baby??
If anyone has a suggestion, solution - so forth - please let me know.
You don't need a "jet" kit, you can easily adjust the pilot screws (try adding 1/4 turn more open) to enrich the idle mixture. If it needs a little more, add another 1/4 turn. Continue this adjustment until the popping quits, then turn them back in 1/8 turn. That way you can still hear the burbling throaty sound that makes ducati owners jealous and causes instant hard-ons.
My '96 VFR is also making that burble sound and pops at the end of deceleration.
I reinstalled the TBros and took extra care to seal up all the joints. That seems to have eliminated 75% or more of the problem, just some very minor decel popping now once in a while on braking but it's out the back so the sound is muted, to me at least. No more explosion at every stop. Cleaned up nicely too..
http://i119.photobucket.com/albums/o124/capnspif/VFR/Tbros%20Exhaust/IMG_9106Medium.jpg
http://i119.photobucket.com/albums/o124/capnspif/VFR/Tbros%20Exhaust/IMG_9086Medium.jpg
[image: View Post]vfrgo, on 14 June 2010 - 12:35 PM, said:
Hey all,
Wondering if anyone has an oppinion, suggestion or solution to what I've observed in the last few days riding.
I have made a drastic exhaust change on my 93.
I went from a stock system to a full two brothers left hand exit system. I've then shorten the TBR silencer by about 6 inches. It sounds crazy!!!
but I've noticed that it does pop on downshifting and engine breaking and the bike seems a bit more rumbly (noticably vibrating to the tune of the exhaust) overall.
I haven't altered anything in the air box department - altho was considering a K&N filter upgrade - nor did I re-jet the carbs.
Do you guys think that this is just a product of a too short of a silencer, or a combination of things - and more importantly - am I running the risk of damaging my baby??
If anyone has a suggestion, solution - so forth - please let me know.
I am guessing you are using premium fuel. The poping noise is unburned fuel in the pipe, try using one tank of regular fuel and poping should stop.
[image: View Post]vfrgo, on 14 June 2010 - 12:35 PM, said:
Hey all,
Wondering if anyone has an oppinion, suggestion or solution to what I've observed in the last few days riding.
I have made a drastic exhaust change on my 93.
I went from a stock system to a full two brothers left hand exit system. I've then shorten the TBR silencer by about 6 inches. It sounds crazy!!!
but I've noticed that it does pop on downshifting and engine breaking and the bike seems a bit more rumbly (noticably vibrating to the tune of the exhaust) overall.
I haven't altered anything in the air box department - altho was considering a K&N filter upgrade - nor did I re-jet the carbs.
Do you guys think that this is just a product of a too short of a silencer, or a combination of things - and more importantly - am I running the risk of damaging my baby??
If anyone has a suggestion, solution - so forth - please let me know.
[image: View Post]MJM, on 20 September 2010 - 03:33 AM, said:
[image: View Post]vfrgo, on 14 June 2010 - 12:35 PM, said:
Hey all,
Wondering if anyone has an oppinion, suggestion or solution to what I've observed in the last few days riding.
I have made a drastic exhaust change on my 93.
I went from a stock system to a full two brothers left hand exit system. I've then shorten the TBR silencer by about 6 inches. It sounds crazy!!!
but I've noticed that it does pop on downshifting and engine breaking and the bike seems a bit more rumbly (noticably vibrating to the tune of the exhaust) overall.
I haven't altered anything in the air box department - altho was considering a K&N filter upgrade - nor did I re-jet the carbs.
Do you guys think that this is just a product of a too short of a silencer, or a combination of things - and more importantly - am I running the risk of damaging my baby??
If anyone has a suggestion, solution - so forth - please let me know.
Unburned fuel in your pipe. Try using a tank of regular fuel instead of premium.Poping will stop. High octane not always good, if engine does not want it it will not use it!
[image: View Post]Paper, on 14 June 2010 - 01:00 PM, said:
http://www.pjsparts.com/catalog/images/7%20-%20Fun%20Stuff/T-Shirt%201%20Back%20PJ%202.jpg
Thats just funny right there, I don't care who you are! Of course VFR Capt. Bob has heard my TL1000 and I don't have a leg to stand on...
Don't worry about the bike burping and farting on decel, it's not doing anything but annoying you. As others have said, just rejet it and be done with it.
A loud pipe might save a life if it weren't subject to the phenomenon
known as the Doppler effect... What that means is the faster your bike
moves the more the sound moving forwards is squeezed and the more the
sound moving backwards is stretched, and the greater the observed drop
in pitch...
Only while your bike is sitting still do you escape the Doppler effect...
http://cache.lexico.com/dictionary/graphics/ahsd/jpg/ASdopple.jpg
[image: View Post]vfrcapn, on 19 September 2010 - 10:26 PM, said:
I reinstalled the TBros and took extra care to seal up all the joints. That seems to have eliminated 75% or more of the problem, just some very minor decel popping now once in a while on braking but it's out the back so the sound is muted, to me at least. No more explosion at every stop. Cleaned up nicely too..
http://i119.photobucket.com/albums/o124/capnspif/VFR/Tbros%20Exhaust/IMG_9106Medium.jpg
http://i119.photobucket.com/albums/o124/capnspif/VFR/Tbros%20Exhaust/IMG_9086Medium.jpg
Those pipes are beautiful, the whole bike is obviously well cared for...
I went to aftermarket pipes on my '97 A) To save weight B) Increase performance and C) To hear that sexy V-4 rumble. I have a Two Brothers Racing full system as well and I love it.. I get a light burble on decel and like you I've been concerned about the exhaust valves. But my plugs are a nice tan color and my operating temps are normal. I seriously don't think it's an issue. One thing I like about the TBR pipes is that they're pretty quiet at low rpms and don't show their true colors till you wind it out.
I drive my cage 50% of the time and on many occasions I have heard an unseen bike behind me. Also, on coming up behind a cage I have often observed the driver look up into his mirrors when he hears me approaching. Anything that makes me more obvious to cage drivers is a plus. I do realize that this is anecdotal, but it is certainly true in my case.
That's an interesting point about doppler effect, Busy. Unfortunately doppler addresses sound frequency, not intensity or the speed of sound itself. So unless you're going over six or seven hundred miles an hour the person in front of you will hear you, just at a higher pitch.
I get a small pop once in a while from my high right Staintune right after starting the bike and warming it up. I wonder if it's the vapor recovery can dumping recovered vaporized gas tank gasses into the combustion system during start/warm up that's alslo causing some of the popping we get, cause the popping totally dissapeasrs right after the bike is warmed up. I don't even get it during close throttle decelleration after that.
Beck
95 VFR
we can get away with these shananigans on later bikes because of fuel injection. right now your carbs hate you. (as does your exhaust valves)
[/quote]
Just curious... Does that mean that the FI is actually sensing and compensating for the lean condition, or does it just not matter as much because the FI meters the fuel more precisely?
no not really. the o2 sensors on 00 plus vfr's(98-99s dont even have these) are only used during steady/light throttle cruising to increase mpg. basically the o2 sensors actually further lean the bike out, and have nothing to do with richening up the bike. carberated bikes are more sensitive to vacume and backpressure changes, as there is no set amount of fuel being injected (ie fuel injection), basically its just a hole that fuel is sucked through due to vacume.
whereas fuel inject bikes, regardless of back pressure will alway inject the same given amount of fuel for any given rpm/throttle possition. there is a map sensor (manifold absolute pressure) though which will compensate (to a certain point) for manifold pressure changes(ie altitude, high flow filters, and throttle possition ect) though....
the only way to tune a fi bike for intake/exhaust mods is with a power commander and dyno time.
but with your bike id say, if you have pair valves plug them. pull the snorkel out and get a high flow filter,
and most importantly find yourselt the nearest dynojet shop and have them properly jet out your bike on the dyno. then your will have absolutely nothing to worry about, as you will know for a fact that your bike is perfectly stoich though the intire opperating range.
[image: View Post]BusyLittleShop, on 22 September 2010 - 01:06 PM, said:
A loud pipe might save a life if it weren't subject to the phenomenon
known as the Doppler effect... What that means is the faster your bike
moves the more the sound moving forwards is squeezed and the more the
sound moving backwards is stretched, and the greater the observed drop
in pitch...
Only while your bike is sitting still do you escape the Doppler effect...
http://cache.lexico.com/dictionary/graphics/ahsd/jpg/ASdopple.jpg
They will still hear you down the road in front of you even with the doppler effect as sound travels much faster than your bike ever will (700+ MPH). I have driven in rush hour city freeway traffic everyday for many years now and I know that I notice sportbikes with aftermarket pipes coming up behind me which makes me look for them to make sure I give them room to lanesplit next to my car. when they pass, unlike sewing machine silent bikes, (specially BMWs) with OEM pipes. Sometime they surprise me when they just suddenly pass and pop ahead of me with almost no sound.. Pipes can be loud without being irritating unlike the loud blatting, fart grenade sounding Harley straight pipes that do rattle people to the core.
Beck
95 VFR
[image: View Post]JZH, on 21 June 2010 - 12:26 PM, said:
[image: View Post]gll429, on 20 June 2010 - 05:36 PM, said:
:mellow: loud pipes dont cause hearing loss??? did you bang your head last week or something?? i dont want to call you stupid but your your clearly not using your noggin! a HUGE percentage of HD rides have hearing loss in the right ear!!!!(pipeside!!)
as for #3 "all about you" its not just about him .. its about YOU TOO if you ever ride in america ! philadelphia has limited DB level on many "main strips" like south street.. a hangout off all ages. a 10 bloc long crawl looking at babes and such.. then the law changed and now if your bike is too loud.. TICKET TIME!
I didn't know about the alleged Harley hearing issue. For most riders (which includes most of the people on this forum), their hearing will be irreparably damaged by wind noise long before any effect from loud exhausts comes into play. You may not know this, but most riders cannot even hear their own exhausts whilst riding--I certainly can't. Besides, if we're just talking about open Harley pipes, then we can move this into the "irrelevant" category in any case...
Don't believe the hype (and yes, I do sometimes ride in America). Obviously, people who like to lecture others often (perhaps without exception) cast their "words of wisdom" in terms of "you" or "us", but this affliction is almost invariably a result of some form of narcisissm. They say "our " rights might be curtailed, but they mean "my" rights might be curtailed. My exhausts are not excessively loud, and it's certainly possible that the OP's TBR is excessively loud, at least in the context of the average "loud" motorcycle exhaust, which is necessarily weighted heavily in favour of American V-Twins. Accordingly, we can lecture ourselves night and day about this and it wouldn't make one iota of difference to the Harley crowd--and make no mistake, that's what will lie behind any sort of legislative or law enforcement solution. As a result, any lectures given here are essentially wasted effort, but if someone really wants to satisfy that particular urge, they should start their own thread. (IMHO.)
Ciao,
Yeah. You ever notice how damn near every person who is foaming at the mouth about "loud pipes" always has an aftermarket exhaust on their bike? That one really gets me. "Their" pipe is always acceptable because it "sounds good", but everyone else's pipes are too loud and "ruining it for the rest of us". Go figure. Do as I say not as I do!! :blink:
And, despite the legendary "doppler effect", I can still hear a Harley or a sportbike coming from about 1/4 mile away. To say nothing about leaf blowers, freeways, screaming children, etc. etc............. :biggrin:
End of thread · 47 posts recovered Wayback Machine snapshot 2 Oct 2010