bonesetter
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posted on 24/8/10 at 09:52 PM |
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TD noise fail help ZX10R
Attended my first TD in the new Mac#1 at Donny tonight and after just half a dozen laps was black flagged for 101DB drive by fail which meant the end
of my night's driving The limit is 98 so that meant 101 was twice as loud...??
Jonny has said I can come along for Thursday's session FOC, which is the final evening session this season.
So, I need to find ways of making the car quieter between now and then...
I was talking to a driver of an MK 'blade fitted with what looked like the identical exhaust can, he said he had been short shifting at 9K
through fear of the noise police. His car sounded fairly loud, as did many of the others there...
Anyway, do I need to just need to find a different can, and if so can you point in the right direction.
Cheers
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austin man
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posted on 24/8/10 at 09:55 PM |
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cant you fit a reducer in the end of the can, sometimes the induction roar is the problem as well. As said some just watch their revs at certain
points where the noise police are sitting
Life is like a bowl of fruit, funny how all the weird looking ones are left alone
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YQUSTA
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posted on 24/8/10 at 10:24 PM |
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not cheap but I had around 5 db reduction
link
"If in doubt flat out"
Colin McRae
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MikeRJ
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posted on 24/8/10 at 11:20 PM |
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quote: Originally posted by bonesetter
The limit is 98 so that meant 101 was twice as loud...??
No, 10dB is a doubling of perceived loudness, not 3dB.
You simply need a bigger/more effective silencer. If you have a re-packable silencer then try repacking it, and make sure you put enough packing in -
too much or too little will reduce the effectiveness.
Using the original bike silencer would be a good move for low noise...
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Flamez
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posted on 25/8/10 at 05:49 AM |
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I had cat fitted as well as a custom air box from .Mac1 and got the noise down to 101.
You won't get it much lower I don't think.
Some tracks are more lenient than others and look for loud days.
my build mac1motorsports
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snapper
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posted on 25/8/10 at 06:20 AM |
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quote:
You won't get it much lower I don't think.
You can get it as low as you want, bigger can, more baffles
An air box over the carbs
A quick fix is a baffle tube fitted in the connecting pipe before the can, Rally Design
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
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RIE
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posted on 25/8/10 at 07:17 AM |
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If you've got a bike can, search ebay for 'db killer' - I've known of them knocking off about 7db in a static noise test (with
a fair amount of exhaust wadding too, lol).
quote: Originally posted by MikeRJ
No, 10dB is a doubling of perceived loudness, not 3dB.
No, he was right first time. From wiki: "A change in power ratio by a factor of 10 is a 10 dB change. A change in power ratio by a factor of two
is approximately a 3 dB change."
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Flamez
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posted on 25/8/10 at 07:19 AM |
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quote: Originally posted by snapper
quote:
You won't get it much lower I don't think.
You can get it as low as you want, bigger can, more baffles
An air box over the carbs
A quick fix is a baffle tube fitted in the connecting pipe
before the can, Rally Design
But there is a limit of noise over performance, not much point in having a quiet bec that can't pull the skin off a rice pudding.
my build mac1motorsports
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ReMan
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posted on 25/8/10 at 07:20 AM |
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I have one of these for when very quiet is needed.
Not been measured, but almost too quiet!
You just need a flange-slip on adaptor also ebayable
http://cgi.ebay.co.uk/Suzuki-Bandit-1200-Exhaust-Can-/130423580842?pt=UK_Motorcycle_Parts
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snapper
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posted on 25/8/10 at 10:12 AM |
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If the exhaust is to loud then you need a much bigger, diameter and length, straight through exhaust this will absorb more noise energy but not stop
the exhaust flow.
However you posted for a quick fix so decible insert is quick and cheap, engine may run richer and you will loose bhp
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
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russbost
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posted on 25/8/10 at 10:42 AM |
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What snapper said is correct, I stock the Db killers, & have tried one in my exhaust & yes noticeably quieter, it will affect power but is a
cheap quick fix.
I haven't got them on the website yet but can do them for £9.95 + £2.95 P & P if it's any help?
I no longer run Furore Products or Furore Cars Ltd, but would still highly recommend them for Acewell dashes, projector headlights, dominator
headlights, indicators, mirrors etc, best prices in the UK! Take a look at http://www.furoreproducts.co.uk/ or find more parts on Ebay, user names
furoreltd & furoreproducts, discounts available for LCB users.
Don't forget Stainless Steel Braided brake hoses, made to your exact requirements in any of around 16 colours.
http://shop.ebay.co.uk/furoreproducts/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
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NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
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snapper
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posted on 25/8/10 at 12:09 PM |
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If the exhaust is to loud then you need a much bigger, diameter and length, straight through exhaust this will absorb more noise energy but not stop
the exhaust flow.
However you posted for a quick fix so decible insert is quick and cheap, engine may run richer and you will loose bhp
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
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Lightning
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posted on 25/8/10 at 01:25 PM |
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These work
Merlin
Motorsport
Steve
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bonesetter
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posted on 25/8/10 at 01:26 PM |
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Thanks for the replies everyone
I'm not sure the dB killer will work with the silencer I have as that needs 210mm of straightish pipe after the can to work (I've been
reliably informed by Russ - thanks)
Is there a muffler which can be fitted to the end of the pipe?
[img]http://flic.kr/p/8vhSMZ[/img]
[Edited on 25/8/10 by bonesetter]
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Lightning
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posted on 25/8/10 at 01:29 PM |
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see above
Steve
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bonesetter
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posted on 25/8/10 at 02:02 PM |
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Decided to go with a Db killer from Russ which he thinks will work, and if it doesn't I can fit fiberglass wool between it and the inside of the
tail pipe...
Fingers crossed
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progers
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posted on 25/8/10 at 02:37 PM |
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quote: Originally posted by bonesetter
Decided to go with a Db killer from Russ which he thinks will work, and if it doesn't I can fit fiberglass wool between it and the inside of the
tail pipe...
Fingers crossed
Not a good option IMHO. DB killers strangle your exhaust and reduce the power of your engine. In some cases it can cause incorrect fuelling resulting
in engine damage in the long term. Don't forget you are dealing with a highly tuned BEC, not a lightly tuned boat anchor :-).
I personally would hate to be running full bore on a trackday knowing that a) you should be going faster and b) wondering how much damage you are
doing to the engine. Db killers are just an emergency device to get you through a day if you have problems.
Its much, much better to bite the bullet and get a larger exhaust can - its the cost of one trackday. Also run with an airbox (if you haven't
already got one).
My ZX12r engined racecar has no problems with noise at trackdays and pumps out its full quota of 180bhp. Its purely down to well designed 7"
exhaust can.
As I said, just my opinion, but based one based on running BEcs for the last 7 years at various trackdays.
Paul
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bonesetter
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posted on 25/8/10 at 03:15 PM |
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Agreed totally
I initially am after, and originally posted for, a quick fix for Thursday's evening session. I suppose I should have just gone for the larger
can option straight away as that would have taken as long to arrive as the dB Killer...
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