Radical Quiet exhaust

Radical Quiet exhaust

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ChrisV

Original Poster:

7 posts

113 months

Sunday 8th February 2015
quotequote all
I'm looking for a quiet exhaust silencer for my Radical SR3 so I can do some testing during a 100db track day,
Anyone have a spare one going for a sensible price or a good contact for one that can be made ?

Cheers Chris Vinall.

BertBert

18,953 posts

210 months

Sunday 8th February 2015
quotequote all
I have got one in the garage you can have. I can't vouch for how quiet it is as it's ages since it has been used, but you are welcome to have it.

Just need to arrange collection/transport from Epsom.

Bert

splitpin

2,740 posts

197 months

Sunday 8th February 2015
quotequote all
BertBert said:
I have got one in the garage you can have. I can't vouch for how quiet it is as it's ages since it has been used, but you are welcome to have it.

Just need to arrange collection/transport from Epsom.

Bert
That's very kind of you Bert clap

If that's static, hmmmmn; best take the supertrapp and/or db eater.

Bert; give it a shake and if it rattles it's phucked - hey, that sounds like another one of those parties you are partial to wink

Sigmamark7

314 posts

160 months

Monday 9th February 2015
quotequote all
I have a SR3RS which came with a "quiet exhaust" and a race exhaust. The quiet exhaust typically came up at about 103dBA, so was a "no go" for Bedford and Castle Combe.
I had a twin silencer system manufactured with a spec to get the car below 100dBA for Combe (my local track), but first time out there, it managed 104dBA, so is now back being remanufactured!
I did once get out at Combe with the quiet exhaust and a supertrapp (with only 2 discs in!), but it strangled the motor so much that even reaching 7500 rpm for the test was a struggle. I'm also not sure what the reading actually was and part of me thinks that they passed it to stop me coming back to the test area for a 6th time.
On track, the car isn't noisy and never troubles the drive by tests and I've tried pretty much everything apart from turning up with a 2 metre extension to move the real exhaust noise away from the mechanical clattering going on at the back of the car, which I think is the real cause of the issue!
So good luck in getting the readings down and if you succeed, please let me know how, because for me, it's now only 105dBA days, to avoid the grief of turning up and getting sent home.

Blatter

852 posts

190 months

Monday 9th February 2015
quotequote all
Sigmamark7 said:
I have a SR3RS which came with a "quiet exhaust" and a race exhaust. The quiet exhaust typically came up at about 103dBA, so was a "no go" for Bedford and Castle Combe.
I had a twin silencer system manufactured with a spec to get the car below 100dBA for Combe (my local track), but first time out there, it managed 104dBA, so is now back being remanufactured!
I did once get out at Combe with the quiet exhaust and a supertrapp (with only 2 discs in!), but it strangled the motor so much that even reaching 7500 rpm for the test was a struggle. I'm also not sure what the reading actually was and part of me thinks that they passed it to stop me coming back to the test area for a 6th time.
On track, the car isn't noisy and never troubles the drive by tests and I've tried pretty much everything apart from turning up with a 2 metre extension to move the real exhaust noise away from the mechanical clattering going on at the back of the car, which I think is the real cause of the issue!
So good luck in getting the readings down and if you succeed, please let me know how, because for me, it's now only 105dBA days, to avoid the grief of turning up and getting sent home.
Chris V - Apologies for the thread hijack.

Hi Sigmamark7, I'm surprised your two-stage exhaust didn't make the grade - I have been getting 96-97 from it since it was built. I was actually disappointed when I turned up at Castle Combe for the first track day with it and the "noise Nazi's" only asked me to rev at 4500rpm. (heh-heh-heh) I came up on their noise-o-meter at 92dB for that one!
Did Neil make your version differently to mine?

Sigmamark7

314 posts

160 months

Monday 9th February 2015
quotequote all
Adrian
The system was based on your system, with only the mounting changed. I went to Donington and a friend measured it at over 102dBA at 7500, so the CC test at 104dBA was disappointing, not least because I had just fitted a new engine and was a bit reluctant to take it to 7500 for the test. I tried everything including removing the rear bodywork to see it that helped (which it didn't!), so I put it back on the trailer and took the car home.
Neil has got the system back, but I'm not sure that he knows any better that I do quite what to do with it, other than fitting some restrictors in the system, which clearly won't help my lap times!
Have you been back to Combe recently?

mad4amanda

2,410 posts

163 months

Monday 9th February 2015
quotequote all
A radical with a bike engine should only be revved to 5500 rpm for a static test !
Worth putting a rev counter in if you dont have one and only have shift lights as they can be troublesome .
There are different exhausts though and the trick is to fit the right one for track days as the race can will fail drive by but a simple bung may well cause backfiring on the overrun and also be called in .
make sure older exhausts are repacked as necessary too

Sigmamark7

314 posts

160 months

Monday 9th February 2015
quotequote all
mad4amanda said:
A radical with a bike engine should only be revved to 5500 rpm for a static test !
Worth putting a rev counter in if you dont have one and only have shift lights as they can be troublesome .
There are different exhausts though and the trick is to fit the right one for track days as the race can will fail drive by but a simple bung may well cause backfiring on the overrun and also be called in .
make sure older exhausts are repacked as necessary too
Hi mad4amanda

From memory, you are down at Brands, so a MSV venue.
At Bedford with the Radical, they wanted 7500 rpm and at Oulton Park a week ago, they wanted 3/4 max revs from my Clio - both MSV venues, so where does the 5500 rpm come from, because it would make a huge difference to my track day choices this year?

ChrisV

Original Poster:

7 posts

113 months

Monday 9th February 2015
quotequote all
Firstly thanks for the info guys, it is somewhat frustrating that we can't just take our wonderful machines out so easily.
Bert that's a great offer of your exhaust Thankyou and I would certainly like to take your offer, however if it works I will be certainly paying you for it. Email me privately on team_akb@yahoo.co.uk with your addressdetails and I'll have it collected.

For proper race cars we are probably asking for too much really, however there should be some solution within reason without too much flow restriction of the exhaust and choking of the engine.


ChrisV

Original Poster:

7 posts

113 months

Monday 9th February 2015
quotequote all
Blatter where did you have your system made ?

Sigmamark7

314 posts

160 months

Monday 9th February 2015
quotequote all
ChrisV said:
Blatter where did you have your system made ?
Chris

Blatter and I both had the systems made by Neil Handbury Racing in Taunton. Adrian's was the first one Neil produced and because it was so well made and was giving the right results, I had a copy made and fitted to my car. I have no idea why the results are so different and Neil now has mine back to try and come up with a solution. I only dropped it back a couple of weeks ago, so I don't know yet what Neil is doing to it.
One thing's for sure, the quality of the system is superb, but I need a guaranteed sub 100dBA reading to make my Radical the perfect car I want it to be!

ChrisV

Original Poster:

7 posts

113 months

Monday 9th February 2015
quotequote all
Well that's handy as I live in Honiton. I'll look him up with an enquiry perhaps that will jog his memory with yours !
Can I ask why you didn't think of trying the Radical quiet exhaust, I was told by them 95db with around 100-101db with the tester.

Sigmamark7

314 posts

160 months

Monday 9th February 2015
quotequote all
ChrisV said:
Well that's handy as I live in Honiton. I'll look him up with an enquiry perhaps that will jog his memory with yours !
Can I ask why you didn't think of trying the Radical quiet exhaust, I was told by them 95db with around 100-101db with the tester.
I have the Radical "quiet exhaust". It isn't quiet!!! Either the Radical noise tester has a hearing problem, or their noise meter is broken. If you buy one, my advice would be to get it on sale or return based on it being as quiet as they claim.
I'm just north of Bristol if you want to borrow my so called quiet silencer to try.

ChrisV

Original Poster:

7 posts

113 months

Monday 9th February 2015
quotequote all
Thanks and a kind offer ! I'll give the guys at Taunton a call tomorrow and go from there.

mad4amanda

2,410 posts

163 months

Tuesday 10th February 2015
quotequote all
Sigmamark7 said:
mad4amanda said:
A radical with a bike engine should only be revved to 5500 rpm for a static test !
Worth putting a rev counter in if you dont have one and only have shift lights as they can be troublesome .
There are different exhausts though and the trick is to fit the right one for track days as the race can will fail drive by but a simple bung may well cause backfiring on the overrun and also be called in .
make sure older exhausts are repacked as necessary too
Hi mad4amanda

From memory, you are down at Brands, so a MSV venue.
At Bedford with the Radical, they wanted 7500 rpm and at Oulton Park a week ago, they wanted 3/4 max revs from my Clio - both MSV venues, so where does the 5500 rpm come from, because it would make a huge difference to my track day choices this year?
Cars are tested at 3/4 max revs apart from bike engined cars which are tested at specified rpm ie 5500 for a 4 cyl 1000 cc + . That is in our Standard operating procedure. Unless bedford have modified the process for radicals as they were having too many pass static and fail drive by ?

splitpin

2,740 posts

197 months

Tuesday 10th February 2015
quotequote all
mad4amanda said:
Cars are tested at 3/4 max revs apart from bike engined cars which are tested at specified rpm ie 5500 for a 4 cyl 1000 cc + . That is in our Standard operating procedure. Unless bedford have modified the process for radicals as they were having too many pass static and fail drive by ?
Could you please point us in the direction of where we can download that MSV Standard Operating Procedure? - I personally need a to print off some copies so I can stick it under the nose of the Noise Tester(s) at Snett (and other MSV Circuits apparently) who seem to have been totally unaware of it for yonks.

Without wishing to be a party pooper, not that what you've said really makes much sense to me in the real world - a) accepting that its total application is by no means mandatory as far as TDs are concerned, the Oh So Grey Book doesn't differentiate between bike or car engines and b) there is no way any four cylinder bike-engine will be in it's meaningfully usable power band @ 5500rpm - not even a 'torquey' (everything is relative!) Busa, let alone a generally significant higher revving modern 1000cc.

Who is trying to kid who and why?


mad4amanda

2,410 posts

163 months

Tuesday 10th February 2015
quotequote all
Bike noise test rev limits are set by the ACU and focus on mean piston speed of 11 m/sec for a 4 stroke engine.

Im sure a quick google will bring up the ACU regs.

U will make inquiries as to the reason for the inconsistency between tracks as I was under the impression we all did the same!



andylaurence

438 posts

210 months

Tuesday 10th February 2015
quotequote all
Sigmamark7 said:
So good luck in getting the readings down and if you succeed, please let me know how, because for me, it's now only 105dBA days, to avoid the grief of turning up and getting sent home.
Sounds like you need to enter sprints instead of track days. 105dB at Combe for the sprints. Come and join in Sports Libre - we're a friendly bunch!

http://bristolmc.org.uk/gws-notice/

splitpin

2,740 posts

197 months

Tuesday 10th February 2015
quotequote all
mad4amanda said:
Bike noise test rev limits are set by the ACU and focus on mean piston speed of 11 m/sec for a 4 stroke engine.

Im sure a quick google will bring up the ACU regs.

U will make inquiries as to the reason for the inconsistency between tracks as I was under the impression we all did the same!
'U will' as in you (not me) will (and post up on here) or you want me to? If the latter, being mildly aware of the mysteries & imaginations of Palmer World, I think I'd probably have more success pushing water uphill?

I'm familiar with the ACU Regs, but referencing the regs of the governing body for bike racing is surely somewhat unlikely to cut much mustard with the noise tester on a Car Trackday is it? Unless I can keep him on one side (unlikely given the central exhaust) so he doesn't notice the other two wheels?

Here's an extract I've just copied and pasted from http://www.msvtrackdays.com/car/faq.aspx. Can't see any mention of 'except if it has a' etc ..........


STATIC NOISE TESTING

These days, all racing circuits have noise restrictions. It is extremely important that we operate in compliance with our set limits. We must act in accordance with the regulations to ensure the future of trackdays for everyone that abides by the rules. Please help us by making your vehicle as quiet as possible before taking part in any on circuit activity. Anyone wishing to have their car tested before a track day is more than welcome to come to one of our circuits during our events and have a noise test free of charge. It takes just a few minutes.

The initial test is a static test which is carried out using a handheld meter. Each car is measured 0.5 meters away from the exhaust at a 45 degree angle when the engine is being held at ¾ of the maximum RPM. In cases where the vehicle has two separated exhausts the measurement will be taken as below from the median point between the two.






mad4amanda

2,410 posts

163 months

Wednesday 11th February 2015
quotequote all
Sorry banana fingers I will..... infact I have already raised a query.