While I dont advocate excessive noise it is clear than many accidents involving motorcyles are caused by other road users being simply unaware that there is a motorcycle in their proximity, lights on in daylight help with this as does an element of noise.
Better to be seen, if not seen it is good to be heard.
Trouble is that it is those that do not relate to motorcyle and who do not "think bike" when driving that are most likely to complain about the noise a motorcyle makes.
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There are many quality aftermarket producers of exhausts.
I have fitted many to my bikes, jetted in the old days of carbs and re-mapped the injection models.
Does it make any difference? Always.
How do you know? I have always had dyno work done before and after, power is improved, torque is enhanced and on the road/track that is noticeable.
Regarding noise, most bikers are a considerate breed, yes there are idiots, but they exist in all walks of life, I personally exercise restraint in built up areas, roll past horses on tick-over, etc, to reduce any possible irritation.
Most of us on here want to enjoy motoring, however many wheels we have, aftermarket exhausts tend to add to the enjoyment.
I suggest there is a bit of 'live and let live'. If you live a truly wondrous life then feel free to comment accordingly, but I am sure the majority of us do something in life that irritates the hell out of others.
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Fotheringon-Thomas.
The dyno does not lie.
Putting an after-market on with no other alterations would yield little or no gain. Changing carb/injection settings yields gains, which is exactly the same method racers use and what the vast majority of bikers will do when fitting after-market pipes/systems.
Edited by Vorny1966 on 02/10/2008 at 13:34
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So your quote of 'rubbish' is ill conceived.
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Rubbish. You can read as well as I can (see web site previously mentioned).
Edited by FotheringtonThomas on 02/10/2008 at 13:39
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We can all read, but interpretation is a different matter.
Perhaps this explanation may help you understand my reasoning:
"A racing exhaust system is designed to provide a useable torque and power in the range where racers need it on the track. The design is adjusted to the engine type, race conditions (riding style), the motorcycle?s center of gravity (handling), the bike?s aerodynamics, and the physical limitations of the motorcycle?s design (so that the exhaust does not touch the ground when the bike is leaned or settled on its shock absorbers). Minimal weight and maximum durability always have to be taken into account."
A racing exhaust also provides useable torque and power in the range where road riders may need. This is achieved by jetting/re-mapping. Improvements in torque and power are just as beneficial to road users as they are on track.
The exhaust touching down can be an issue on standard exhausts on the road as on the track, so any benefit there is just as valid.
Weight and durability are just as valid on the road, weight loss as a result of change is beneficial to handling.
"During development and manufacturing we also have to take into consideration the regulations on maximum exhaust system noise levels for various competitions (FIM MX, FIM SBK, FIM ENDURO etc.), which differ from competition to competition."
There are noise limits on track, this comment recognises that fact
"Since racing exhaust systems are custom manufactured for custom racing bikes with special engine settings, gear-boxes and frame designs, such systems usually cannot be mounted on stock motorcycles, and if they are, the system?s functioning is not adjusted to the stock engine settings, which of course has a major effect on the engine performance and the ride itself. In practice this means that certain systems work poorly at the low revs necessary in street use."
My earlier note recognises this fact. Systems do not work on stock settings, hence my comments about jetting and re-mapping, although some of the more advanced injection settings can recognise the change of exhaust and compensate accordingly. Without this work, the low-rev issue arises from the engine running too lean.
"The same goes now as it has done for the previous 50 years or more - which is that chopping off your bike's pipe, shoving a bar up the silencer, or buying a "performance" exhaust is rather unlikely to help your BHP in any meaningful way."
This is where my comment about the dyno does not lie comes in. The majority of bikes out there with race systems will have been properly set up with jetting/re-mapping that has proven gains on a dyno. Perhaps you can let myself and fellow forum members know what objective data you have to refute this fact ?
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The majority of bikes out there with race systems will have been properly set up with jetting/re-mapping that has proven gains on a dyno. Perhaps you can let myself and fellow forum members know what objective data you have to refute this fact ?
First, establish your "fact". The "majority of bikes out there with race systems" are unlikely to be relevant in this context to the OP about a *road* bike.
I agree with a previous poster - the number of "properly designed aftermarket systems" is likely to be quite small. Also, any (possible) "performance gains" resulting from this "tuning" are also likely to be small.
Re. "let myself and fellow forum members know". You should not have to use this shallow tactic.
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SNIPQUOTE!Re. "let myself and fellow forum members know". You should not have to use this shallow tactic.
The OP can be resolved by looking at an aftermarket accesory retailer, many of them will have two ranges for sale, for road use and not for road use.
There is a huge number of exhaust manufacturers that retail after-market pipes. Reputable manufacturers such as Akrapovic, Yoshimura and Micron feature quite heavily within the race scene and provide end cans and systems for the retail market. Their systems will be fully developed and designed on a model by model basis. Their business relies heavily on reputation and as such I think it would be fair to say that their systems would be properly designed.
Performance gains. I can only speak with authority from my own experiences here, so I quote the following two gains I have experienced. I have chosen these two as they are significantly different in terms of carburation type and exhaust. The first instance was a re-jet and end can, the second a re-map and full system. Both properly matched, 'race' stamped, with the following dyno results at the back wheel;
Kawasaki ZX7R 108BHP > 122BHP 13% increase (micron)
Suzuki GSXR1000 136BHP > 158BHP 15% increase (promotive)
Gains such as this are far from small IMO.
In terms of shallow tactic. You have made a statement, I have invited you to add further detail to back up your comment, just as I have done to back up my statements.
Edited by Dynamic Dave on 02/10/2008 at 14:46
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(your tuning) The first instance was a re-jet and end can the second a re-map and full system.
"I fitted a new exhaust pipe and it gave me XXBHP more, and I only had to change the jet size (wot no needle changes?), and "re-map" the thing as well..." Oh well, then you win.
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On the older carb'd bikes, changing the exhaust usually required rejetting and dyno time to get the bike set up. I changed the 4-2 on my ZZR600 for a 4-1, with BSAU stamped can, and the bike ran like a dog. It was horrible - lumpy and with flat spots everywhere. After 3 hrs on the dyno and a stage 1 Dynojet kit, I had 103 bhp (99 quoted by the manufacturer), but had lost some of the midrange torque. Quite exciting when it's only pulling 195kg.
The Quill can on my bike is very interesting actually. It's fully road legal (BSAU T3 stamped), and uses back pressure to open a ballvalve beyond certain RPM to divert some of the exhaust gases "straight through" the silencer. The result is a quiet bike at tickover and town revs, but a race can scream at high revs. I like it a lot.
MOT rules now state that anything not stamped "NOT FOR ROAD USE" (an instant fail) is down to the testers discretion. These labels are often stamped very shallow into the case, meaning 5 minutes with the T-Cut and they're gone.
Cheers
DP
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After 3 hrs on the dyno and a stage 1 Dynojet kit I had 103 bhp (99 quoted by the manufacturer) but had lost some of the midrange torque. Quite exciting when it's only pulling 195kg.>>
A rather optomistic dyno DP ;-) IME you would need to heavily breath on a ZZR 600 to get a genuine 103 bhp at the wheel. The latest R6, ZX6R et al are getting aroung 112 and my Akrapovic etc equipped ZX7R was only around 115, it was 105 std against a Kawa claimed 122.
Your point is clear though, my ZRX 1100 in standard form would produce about 95BHP at the wheel, the ZZR1100 with a version of the same engine produces around 125bhp at the wheel (147bhp claimed by Kawa) so it is easy to see how jetting filter and pipe can take the ZRX to 120bhp (and with ZZR1100 cams 130bhp is easy).
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Thanks for the replies everyone. Some useful stuff there, as well as a bit of debate.
Some bikers are selfish and run VERY loud pipes that are antisocial. I don't approve of that behaviour, although I wouldn't lose sleep over it. As has been said, sound can be a useful way to raise car driver awareness of a bike's proximity, although how far that does actually help I don't know when windows are up and stereo on (anyone seen any research?). But I digress.
I'm NOT planning to put a race exhaust on any bike. I will buy the nicest, best looked after example I can find, the pipes are a side issue. I really wanted to know if I'd need to factor in new pipes to pass MOT or be insured as and when I buy the bike. Replies suggest that it's not a big problem, although I would prefer standard or BS marked cans.
For info, I'm currently looking at the Honda VTR 1000 Firestorm and the BMW F650CS (there is a separate thread on that), depending on whether head or heart wins (with influence from wife). The BMWs I've seen are all on standard pipes. Some of the Firestorms are on aftermarket pipes, hence my question. I'll be using it for a commute in to London plus some fun.
As a bit of a petrolhead, I do like the sound of a nice engine. I have owned a Ducati Monster 900 with standard pipes that sounded really a bit like a hairdryer (pity cos it went like stink), and a 350 powervalve on legal microns that sounded lovely and burbly in the way only a 2-stroke twin can. A few more horsepower is nice, but to me not really an issue- if I wanted to go faster, I'd buy a bigger bike. Useable power is an issue, and I would be keen, whatever pipe a bike has, that it enhances rideability rather than hinder it.
Hope that makes sense.
Thanks for your help,
Alex.
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Some bikers are selfish and run VERY loud pipes ...... I wouldn't lose sleep over it.
You might not lose any sleep over it, but people in their beds might ~ young children, bed-ridden invalids, night-shift workers etc.
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>> Some bikers are selfish and run VERY loud pipes ...... I wouldn't lose sleep over it. You might not lose any sleep over it but people in their beds might ~ young children bed-ridden invalids night-shift workers etc.
Or almost anyone if some idiot goes off to work on his super-loud bike at 6:30am every morning.
Saying that it makes bikes more likely to be heard by car drivers ignores the fact that it makes bikes more likely to disturb people who may be at home, walking along the pavement, just going about their daily business.
If you are worried that a car driver hasn't noticed you, you have a horn; use it.
Having a loud exhaust is like driving everywhere with your horn blaring.
There no excuse, really, it's just anti-social.
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I'm currently looking at the Honda VTR 1000 Firestorm and the BMW F650CS (there is a separate thread on that) depending on whether head or heart wins (with influence from wife).
These are both interesting machines. May "the influence" assist you!
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L'escargot- I was writing metaphorically re lost sleep, so probably not the best choice of phraseology under the circumstances! I'm not an advocate of loud pipes that disturb, but in most situations the sound of a motorcycle will not be readily discernible above general road noise, aircraft, buses, lorries, shouting roofers (I have these next door and the language is colourful and florid!). Where the sound is loud enough to disturb (ie considerably more than ambient) it should not be tolerated. I do condemn bikers with very loud pipes that ride fast through quiet villages on weekend mornings, that must be hard to tolerate.
FT- the influence has yet to decide where it lies at the moment. I suspect head (BMW), but she may bowl a fast one and come up for heart! Whichever, the process will be smoother if she is in favour.... :-)
Thanks,
Alex.
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There does seem to be a less than responsible attitude from a lot of the 'newer' biking fraternity at present, seemed to start within the last few years.
I run a loud exhaust, but feel I am considerate when going through built up areas to keep noise levels low.
But, the inconsiderate behaviour extends to lack of respect for 30/40 limits and other road users. There is a fair bit of accusation of police victimisation too from bikers. Guess what guys, we have ourselves to blame!
There has been a real shift in behaviour from both sides. I did the majority of my road riding in the 90's, obeying limits in built up areas, driving considerately in the presence of other road users, and that seemed to be the behaviour of all the bikers at the time. There seemed to be respect from the police, if you were pulled, it was usually for a word and sent on your way. This even extended to some quite rapid progress in the non built-up areas.
Now, there seems to be mass ignorance of limits and other road users and as a consequence, bikers feel the full weight of the law. Shame.
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The only reason I can think of why motorcyclists want to make their bikes noisier is to annoy other people, since it is rarely a nice sound that eminates from a noisy bike!
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The only reason I can think of why motorcyclists want to make their bikes noisier is to annoy other people since it is rarely a nice sound that eminates from a noisy bike!
What bike do you own/have owned Spud ?
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What bike do you own/have owned Spud ?
What's the relevance of the question?
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SQWhat's the relevance of the question?
Because I am interested given Slug's statement. I hoped the response would add credibility to the statement.
The only reason I can think of why motorcyclists want to make their bikes noisier is to annoy other people since it is rarely a nice sound that eminates from a noisy bike
Edited by Dynamic Dave on 02/10/2008 at 20:00
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Slug's statement.
Who is this "Slug"?
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typo, slug should have been spud....
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I disagree with that to some extent - some think a noisier pipe=lots more power - but you're right in that not many racing machines are found on the roads!
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The last but one owner of my Bandit swapped the OEM rear section for one made by Scorpion, with a removable baffle (I have never bothered - the guy who sold it to me said that it made the power delivery a bit peaky). Apparently this will nudge the BHP a little way over 80.
More importantly, it makes the bike look better - the standard exhaust on these looks like it should say Heinz 57 Varieties on the side, and is ridiculously heavy (goodness knows that the poor machine has enough to carry with 16st of me on it!) The Scorpion version is about 2/3 the diameter and half the weight. Reason enough to fit one, IMO.
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I think some people here don't appreciate the sound of an exhaust.
I've been smitten since I first heard a moggie minor on the overrun.
Have you never heard Renault playing national anthems on their F1 engines?
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there do seem to be some polarised opinions on here re this subject
I have an early Honda Blackbird (carb not fuel injection), which came with everything standard...(1137cc large Sports Touring bike for those not in the know)
On a holiday abroad with 11 other bikers, they nicknamed it the 'stealth bomber' because it was so quiet. If you were on a good run on an 'A' type road, sat hovering, waiting to overtake someone else, who wasn't aware of your presence, because they weren't using their mirrors properly and you weren't willing to chance it..then you just had to remain patient, sometimes for quite some miles
since my brother got hold of it at a service and tweeked it, which included louder exhausts, dyno jet kit and K&N air filters i've found that problem has completely gone away, because you can drop it into a lower gear than you really need and all of a sudden, they're aware of your presence, because they can hear you...far safer. I've even used it in traffic jams when filtering.
the other thing is, it is unbelievably awesomely quick off the mark. It was never a slouch, but i now have to be very careful not to have the front end come up, whereas before i could easily use full throttle off the line.... not any more.
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