Quieten me down for CCombe??!!
Quieten me down for CCombe??!!
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redleicester

Original Poster:

6,869 posts

274 months

Thursday 27th July 2006
quotequote all
Chaps, thought I'd post this in general so all Chim / Griff drivers see it both past and present. A couple of us are doing the Bookatrack day at Castle Combe next wednesday, ad are rather worried that we're way over the noise regs.

Ruling is 100dB at 4500 / 45 degrees - last time I checked, my Chim 450 was closer to 108-110.

Some suggestions please for track-day silencer options?

stainless_steve

6,052 posts

287 months

Thursday 27th July 2006
quotequote all
Only rev it to 4,000 rpm

edited to add or buy a trackday silencer from ACT

www.actproducts.co.uk/trackdays.php

Edited by stainless_steve on Thursday 27th July 18:22

redleicester

Original Poster:

6,869 posts

274 months

Thursday 27th July 2006
quotequote all
Aye that ole chesnut..... used to do that in my old Chim..... unfortunately, in the current one, 4k is still well over 100dB....

stainless_steve

6,052 posts

287 months

Thursday 27th July 2006
quotequote all
see above then,just edited

redleicester

Original Poster:

6,869 posts

274 months

Thursday 27th July 2006
quotequote all


Ta chap, any other options?

gridgway

1,001 posts

274 months

Thursday 27th July 2006
quotequote all
you can buy add on bits from the motorsport/spares place at CC (Merlin?). The way it works is that they give you a suitable add on bit to try, you get noise tested and if it works you buy it and if it doesn't get you quiet enough then you dont buy it!

If you are really are 108-110 db then I reckon no (sensible) amount of add-ons in the world will get you down to 100 for the test. IME the bolt on bits can get you down 2-3db, not from 108 to 100.

mind you (and I'm sure you are, but) are you sure you are at 108 db static? That's really very loud indeed!!

Graham

redleicester

Original Poster:

6,869 posts

274 months

Thursday 27th July 2006
quotequote all
To be honest Graham, I'm not sure about exact volume - or to be precise, I trust my meter, and not those at Combe - last time I was there (two years ago before the furore about noise) the claimed my totally standard Chim400 was 99.5 and passed the car in front of me which was a decat with sports exhausts!

Hence my readings have given me 106dB ish with a following wind, and thus I'm trying to plan for the worst and assume that CC may insist it's far more than that. I think the full blot-on ACT approach is likely to be the best option

big_treacle

1,727 posts

289 months

Friday 28th July 2006
quotequote all
gridgway said:
you can buy add on bits from the motorsport/spares place at CC (Merlin?). The way it works is that they give you a suitable add on bit to try, you get noise tested and if it works you buy it and if it doesn't get you quiet enough then you dont buy it!

If you are really are 108-110 db then I reckon no (sensible) amount of add-ons in the world will get you down to 100 for the test. IME the bolt on bits can get you down 2-3db, not from 108 to 100.

mind you (and I'm sure you are, but) are you sure you are at 108 db static? That's really very loud indeed!!

Graham


I had to get some of those silencers at CC. As I remember my Chimaera (with baffles removed) was measured at 106.9db & the bolt on silencers dropped it to 97db.
So you might be OK. I'd say go there, try it and see what happens.
BTW the bolt on silencers were around about 100 quid.