Cadwell track day

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the duke · #31 Post by **the duke** » Sat Apr 21, 2007 1:29 pm

I might be going as well if i can afford new tyres and a track day in the same month.

How loud is 105 db. Cos my bike is LOUD, a pair of old art cans with all the wadding now blown out.
I might have to throw the standards on but i don't really want to.

Where do they hold the db meter when testing as my mate could get hold of one for me to use.

Ben

Nooj · #32 Post by **Nooj** » Sat Apr 21, 2007 7:13 pm

105 is quite loud apparently, no idea how they test it.

Gio · #33 Post by **Gio** » Sat Apr 21, 2007 10:09 pm

If you take 80Db as the base then for every 3 increase ie, 80/83/86 double the volume so 105 Db is about 8 times as loud as 80.

Much more than that and your eardrums could be ruptured (blood etc.)

D-Rider · #34 Post by **D-Rider** » Sat Apr 21, 2007 11:21 pm

Gio wrote:If you take 80Db as the base then for every 3 increase ie, 80/83/86 double the volume so 105 Db is about 8 times as loud as 80.

Much more than that and your eardrums could be ruptured (blood etc.)

Every 3dB represents a doubling of acoustic power rather than volume. So for your example in comparing 105dB with 80dB (well lets compare with 81dB as it gives a whole number of multiples of 3dB):
105dB-81dB = 24dB

24 dB represents 8 doublings of power .... or 256 times the acoustic power.

It won't sound 256 times as loud though as the ear doesn't have a linear response.

Nevertheless, 105dB is a lot louder than 80dB.

This link gives some examples that may give an understanding of what you may experience at different dB levels:
Sound Pressure

Nooj · #35 Post by **Nooj** » Sun Apr 22, 2007 5:21 pm

Subway (not the sandwich shop) 100db

I dunno though, my Dad's a noisy eater.

Gio · #36 Post by **Gio** » Sun Apr 22, 2007 10:12 pm

D-Rider wrote:
Gio wrote:If you take 80Db as the base then for every 3 increase ie, 80/83/86 double the volume so 105 Db is about 8 times as loud as 80.

Much more than that and your eardrums could be ruptured (blood etc.)
Every 3dB represents a doubling of acoustic power rather than volume. So for your example in comparing 105dB with 80dB (well lets compare with 81dB as it gives a whole number of multiples of 3dB):
105dB-81dB = 24dB

24 dB represents 8 doublings of power .... or 256 times the acoustic power.

It won't sound 256 times as loud though as the ear doesn't have a linear response.

Nevertheless, 105dB is a lot louder than 80dB.

This link gives some examples that may give an understanding of what you may experience at different dB levels:
Sound Pressure

I wasn't aware that ears heard in acoustic alogrithms.

Samray · #37 Post by **Samray** » Sun Apr 22, 2007 10:19 pm

Gio wrote:
I wasn't aware that ears heard in acoustic alogrithms.

Some peoples hardly hear at all do they Gio?

the duke · #38 Post by **the duke** » Tue Apr 24, 2007 11:16 am

Two Questions:

At what revs/distance from the bike do they measure the DB

Has anyone had any experience of DB killers. How much do they take off the noise in case my bikes to loud.

Also. I'm booked in now, for the intermediates. Hope i'm in the right class as i've not done a track day for the last five years.
Hope the weather doesn't spoil it and see you there

Ben

DavShill · #39 Post by **DavShill** » Tue Apr 24, 2007 1:51 pm

See you there Duke. The last time I was tested was at Oulton. The guy stood immediately behind the bike (a couple of paces) and held the sensor at waist hight in front of him and I had to hold the revs steady at 7k.

Don't really know what 105db sounds like .. so I'm not much use really am I

I am running twin port Blue Flame Evo - Baffles in but bungs on the lower port removed. I will be taking the bungs and circlips just in case they need to go back in.

Cheers

Nooj · #40 Post by **Nooj** » Tue Apr 24, 2007 5:27 pm

Ridiculous really, do they test the BSB bikes and refuse them entry if they're too loud? And Cadwell's in the middle of nowhere, who's going to hear it any way? Fuckin' stupid if you ask me.

Samray · #41 Post by **Samray** » Tue Apr 24, 2007 6:30 pm

Nooj wrote: do they test the BSB bikes and refuse them entry if they're too loud?

Most tracks have a very limited number of w/e's a year they can make that sort of noise.

scottyni · #42 Post by **scottyni** » Wed Apr 25, 2007 8:23 am

not sure if this is relevant.. i ran my falco with the old non-baffled twin ports at cadwell last august. noone came near the bike to test for noise. nothing was said either.

this may be a new thing they have started.

did find out that my bike could be heard all round the track while sitting at the mountain

be interesting to know if they do check the bikes, if they do then let us know by what means. might do another there and donny but if they check then i'm most probably stuffed.

when is the trackday?

sabestian · #43 Post by **sabestian** » Wed Apr 25, 2007 11:41 am

the duke wrote: Has anyone had any experience of DB killers. How much do they take off the noise in case my bikes to loud.

I used to use Ebay universal type with my Suzuki SV's M4 racing can. It was much quieter, fueling unaffected (carbs, mind), fitting reasonably easy (you may need to drill a small hole for a retaining screw - I managed with worm drives), cheap too (tenner).

the duke · #44 Post by **the duke** » Wed Apr 25, 2007 12:10 pm

Thanks seb

Anyone going there in a van. I will be riding there but i was wondering if someone had a van if i could leave some bits and bobs there.
Just a small rucksack. I was going to take the mirrors off and tape up the lights, then a bit off food and drink. Also a tyre pressure guage.

Does anyone know how many psi you should drop for going on the track.

Ben

Pierre · #45 Post by **Pierre** » Wed Apr 25, 2007 2:45 pm

They test the noisest bikes at croft now, they never bothered last year and I saw them testing race bikes at the auto66 meeting on saturday so I'm gonna take my standard cans with me just in case like

And there'll be plenty of vehicles to throw stuff in duke, you cant miss mine. Its the metalic gold honda 4wd pimpmobile with a fightered falco and 300yr old cbr6 on a hand painted blue trailer

edit: i run 30/30 cos I know no better although I did try 75 in the front but didnt like it