Noise testing of race bikes - what's the answer?

[budda]

Stupid F-in rules - they are race bikes - they are meant to be loud.


Having said that a old banger with a open cone pipe makes a shit of a lot of noise! It is very surprising how much a small reverse cone shuts it up.

Theres a whole lot of science in effectively muffling the internal combustion engine without losing too much power / torque ...... havent looked at the current FIM rules, but the old ones used to stipulate the factoring-in of considerations like conrod length etc.

This goes some way to explaining why there is such a difference in sound between engines of roughly similar specs - a TT500 on a straight pipe doesnt sound anything like a Manx Norton. Listen to the 125's - some have that beautiful "crack" to them, some sound like a farmbike with a rusted out header pipe ....... but they're all the same size and roughly similar state of tune(ish)

If we all just take some personal responsibility for our OWN bikes noise, this problem is very nearly dealt to ... the only guy to get sent home for excess noise will be that OTHER guy, who clearly doesnt give a shit about his access to race tracks

[codgyoleracer]

The F5000's run a top-hat type cover over the stacks to deflect the sound .... the more astute among you will note I said SOUND - there is a difference between what we perceive as mechanical music, and what the trendy life-styler calls anti-social noise.

The days of "noise equals horsepower" are long gone, and NOT by MNZ's doing. For example, the limit for Speedway tracks is also 95db, and some of those suckers are churning out 700HP, and regularly test at around 92-93Db ....... as did a couple of the Supers.

This isnt about being punitive, its about futureproofing our Sport ....... as has been pointed out, each decibel increase is not an increase by a factor of one, its a lot more than that. All thats needed in the immediate future is for a bit of muffler repacking.

Now now now, stop making sense. This is KB here where we need inuendo and controversy, - how dare you post something reseembling the truth of the matter...... :-)

We have the answer already, when the council nerd turns up the Sherriff is gonna punch him in the nose and send him packing, problem solved ..........

In the future engines will rev ever higher and higher, so the problem indeed is not going away in a hurry, in fact if i had to place my hard earned money on the future of noise control - i would say that 95db is as high as it will ever go - with a strong likelhood that it will be reduced further over time (particularily if the 95db limit is disregarded willy-nilly)

[budda]

Now now now, stop making sense. This is KB here where we need inuendo and controversy, - how dare you post something reseembling the truth of the matter...... :-)

We have the answer already, when the council nerd turns up the Sherriff is gonna punch him in the nose and send him packing, problem solved ..........

In the future engines will rev ever higher and higher, so the problem indeed is not going away in a hurry, in fact if i had to place my hard earned money on the future of noise control - i would say that 95db is as high as it will ever go - with a strong likelhood that it will be reduced further over time (particularily if the 95db limit is disregarded willy-nilly)

now LOOK ..... if we carry on all this agreeing with each other, your reputation is shit mate ! I'm of the opinion that there are two main reasons the Supers had the majority of the noise issues at HD - 1/ the cloud cover came in and effectively put a lid on the big pot that is HD, so the sound couldnt get OUT, and 2/ I reckon there might just be an issue with some of the ignition-cut shifters being used in this class - when they cut back in, there's a pretty loud "bang" for a nano-second, but obviously long enough to spike the readings.

But it has to be said, for so many to be that far over so quickly, they must have been perilously close to the limit already. Its just not possible to compare readings from other tracks, it is the "on the day" reading that matters, and, as we've now seen, these readings CAN AND DO change throughout the day. For the cost of half a dozen rivets and some packing, I'd prefer to safeguard my ability to ride at purpose-built racetracks thanks

[Biggles08]

now LOOK ..... if we carry on all this agreeing with each other, your reputation is shit mate ! I'm of the opinion that there are two main reasons the Supers had the majority of the noise issues at HD - 1/ the cloud cover came in and effectively put a lid on the big pot that is HD, so the sound couldnt get OUT, and 2/ I reckon there might just be an issue with some of the ignition-cut shifters being used in this class - when they cut back in, there's a pretty loud "bang" for a nano-second, but obviously long enough to spike the readings.

But it has to be said, for so many to be that far over so quickly, they must have been perilously close to the limit already. Its just not possible to compare readings from other tracks, it is the "on the day" reading that matters, and, as we've now seen, these readings CAN AND DO change throughout the day. For the cost of half a dozen rivets and some packing, I'd prefer to safeguard my ability to ride at purpose-built racetracks thanks

My exhaust is a brand new Two Brothers full system so the packing is as tight as it will get. It still smells new due to the packing burning in. On the Saturday (overcast and cloudy) I was told my bike read 103Db!?!? On the Sunday we did our own noise tests on the side of the track also with a correct, calibrated Db indicator and we were sitting on between 94 and 95Db. I was told that in fact when the Yamaha's went past the Db reader spiked at 98Db yet they definitely sounded quieter than my bike. Goes to show the 'it sounds a lot louder' argument doesn't really mean shit when it comes to the actual Db reading.

I stick to the original point, why is it we are getting pinged for being too noisy (I know its in the rules etc but not the point here) when in fact we are by comparison to other motorsports not close to the same Db levels. I think it is a reasonable question that no one seems to be able to answer (appart from it is the rules). Do these other motorsport disciplines have the same limit of 95Db? If so, why are they continuously allowed to run meetings (ie drags)?

[budda]

My exhaust is a brand new Two Brothers full system so the packing is as tight as it will get. It still smells new due to the packing burning in. On the Saturday (overcast and cloudy) I was told my bike read 103Db!?!? On the Sunday we did our own noise tests on the side of the track also with a correct, calibrated Db indicator and we were sitting on between 94 and 95Db. I was told that in fact when the Yamaha's went past the Db reader spiked at 98Db yet they definitely sounded quieter than my bike. Goes to show the 'it sounds a lot louder' argument doesn't really mean shit when it comes to the actual Db reading.

I stick to the original point, why is it we are getting pinged for being too noisy (I know its in the rules etc but not the point here) when in fact we are by comparison to other motorsports not close to the same Db levels. I think it is a reasonable question that no one seems to be able to answer (appart from it is the rules). Do these other motorsport disciplines have the same limit of 95Db? If so, why are they continuously allowed to run meetings (ie drags)?

You're missing the Point young man ...... it is the OFFICIAL meter, in the OFFICIAL place, in the OFFICIAL test manner that makes the OFFICIAL reading. Your bike was head and shoulders loudest machine at HD either day, by ear and by meter.

The reality is, you are being asked to do what you agreed to when when you entered, and stick to OUR rules ...... if we all take some ownership of the problem, we ALL stave off the attentions of the Noise Nazis for as long as we can. What other Organisations may or may not get away with makes exactly no difference to us in OUR battles with the nay-sayers - still, you could always take up Drag Racing, if noise is what does it for you.

Oh, and TIGHT muffler packing has very little sound absorption qualities ....... firm but not tight is the way to go - like most good things in life

[Deano]

Council nerd ?

Noise nazis ?

Lol

Nasty !!

[Biggles08]

You're missing the Point young man ...... it is the OFFICIAL meter, in the OFFICIAL place, in the OFFICIAL test manner that makes the OFFICIAL reading. Your bike was head and shoulders loudest machine at HD either day, by ear and by meter.

The reality is, you are being asked to do what you agreed to when when you entered, and stick to OUR rules ...... if we all take some ownership of the problem, we ALL stave off the attentions of the Noise Nazis for as long as we can. What other Organisations may or may not get away with makes exactly no difference to us in OUR battles with the nay-sayers - still, you could always take up Drag Racing, if noise is what does it for you.

Oh, and TIGHT muffler packing has very little sound absorption qualities ....... firm but not tight is the way to go - like most good things in life

Lol...no budda, you're missing MY point...I know all you have said re the rules is correct and I do not debate that (I would debate the fact my bike was the loudest there however), my question is are the other organizations as you say "getting away with it" or do they have different rules?

[Tony.OK]

Lol...no budda, you're missing MY point...I know all you have said re the rules is correct and I do not debate that (I would debate the fact my bike was the loudest there however), my question is are the other organizations as you say "getting away with it" or do they have different rules?

Just get a decent system like akrapovic n chuck the nasty 2 bros on for the drags bro

[ellipsis]

are the other organizations as you say "getting away with it" or do they have different rules?

...it's just politics...a F5000 event would generate lots of money, easily overlooked by the powers that be..but they have to be seen to be doing something...I bet any db restrictions would be non existent if we could score an F1 GP on our fair shores...it is a fairly dubious system at best that we have to adhere to...my bucket and a B50 not allowed back out at Levels, not complaining, just puzzled, when you know you are chasing far noisier machines ...but at the end of the day the rules are the rules...

[slowpoke]

Nope I can't...but thats why the question was asked, how do the drags get around it? How can the Formula 5000's race a couple of weekes earlier on the same track (Hampton Downs) and get away with it?

It's just part the complexity of the whole noise issue: your 600 does what, 16000rpm? Versus an F5000 car doing about 9000rpm? Huge difference in pitch and how the noise travels, and how it is perceived. I've been to the Lady Wigram meeting with a field of F5000's and they just don't seem that loud, whereas some bikes are farkin' ear piercing.

Seems to me there needs to be some action on both sides of the debate: make sure our own house is in order regarding noisy bikes, and also make sure the tests are done in a fair manner. I don't know where the tests were carried out but there's absolutely no point in having a dBmeter NATA certified if you are going to point it at a bike with a concrete wall, banking and apartment blocks directly behind it. It would be interesting to see the difference in results comparing readings taken on the front straight at HD and another set after turn 1 with it's comparatively wide open spaces.

But ultimately you don't wanna be in the position of having that argument, if you're that close then the issue is gonna rear it's ugly head sooner or later.

[Str8 Jacket]

Council nerd ?

Noise nazis ?

Lol

Nasty !!

Just push that morphine button mate!

[wayne]

if bike passes at the first three rounds,
no changes between how could if fail,
were the other 3 readings wrong ?
someones having fun , stop them ?

[lukemillar]

You're missing the Point young man ...... it is the OFFICIAL meter, in the OFFICIAL place, in the OFFICIAL test manner that makes the OFFICIAL reading. Your bike was head and shoulders loudest machine at HD either day, by ear and by meter.

The reality is, you are being asked to do what you agreed to when when you entered, and stick to OUR rules ......

That is fair enough, but you have to admit, there has to be some sort of guidelines to test your bike before you rock up on race day or at the very least, static testing at scruiteneering. Otherwise how are you supposed stick to the rules before you do your first session and get told it has failed if the only benchmark is the official meter at the track!?

[malcy25]

if bike passes at the first three rounds,
no changes between how could if fail,

Can think of two straight away:
1) cloud level / atmospheric conditions
2) packing is a consumable item. It wears out.

Here's a question. Why do race bikes have to be so loud as to be just within the limit?

[codgyoleracer]

That is fair enough, but you have to admit, there has to be some sort of guidelines to test your bike before you rock up on race day or at the very least, static testing at scruiteneering. Otherwise how are you supposed stick to the rules before you do your first session and get told it has failed if the only benchmark is the official meter at the track!?

On some days ALL noise will be louder or quieter due to the surrounding weather /humidity etc. MNZ are good , but to try and out dodge nature, is probably a big call....

Makes sense tho to have.

1) Standardised meter type and brand
2) Standard location established for all tracks (position, distance etc)
3) Basic training of operator or an easy to follow guidline sheet that any muppet can follow
4) 95 is the max, so would suggest a "heads-up" warning at 93 be given to riders that reach that
5) Three passes at 95 or more in a single session and ya gotta get it fixed
6) Continued passing after fixing & still over limit - Welcome to Mr Black flag


Whilst the above guidlines might make 'common sense" they DO NOT fit in with the current rule book + they DO NOT fit in with the sound safetycrats (particularily line 5)