Yamaha TRX850 Enthusiasts Forum

Just looking at track opportunities - sadly the PB thing at Cadwell is just too far away - but there are bike trackdays at Castle Combe which is only an hour from me...

Their requirements include standard exhausts (ha - fat chance there!) but in any event a 105dB limit. So, given that our bikes do tend to sound better when the volume's turned up a bit, is a TRX with a set of sport pipes likely to get through a 105dB limit?

I know it's hard to judge, but my Akra is a pretty growly chap and I'd hate to book only to be told I'm too loud..

G

IIRC you have to have standard cans fitted to get in. Even if I'm wrong on that - it's worth getting it checked out properly if you can Greg, they're VERY strict on noise limit there as they've had a lot of trouble with local residents. A guy of my local forum was turned down with a Micron on a ZXR400.

When CC say standard exhausts that is exactly what they mean - and they are very very strict - I wouldn't expect any race pipe to get through

As for the 105db limit, it all very much depends on how and where it is measured

Last time we were at Cadwell, Out of the 3 Daves 2 of us were at 96 db and Trixynut was at 99 db. That at 5000 revs, held. A GSXR 1000 failed and he was told to he couldn't run, and no sticker.

Dave E.

slow codger wrote: Last time we were at Cadwell, Out of the 3 Daves 2 of us were at 96 db and Trixynut was at 99 db. That at 5000 revs, held. A GSXR 1000 failed and he was told to he couldn't run, and no sticker.

Dave E.

5,000 rpm is the ACU suggested level for twins - should be measured 1 metre behind bike and one metre from floor.

Last time mine was measured like that it 104.7

Well If it was supposed to be a metre............. It was nearer 2 ft as I remember. And he was so busy watching the exhaust that he didnt notice that most of us were in the 4500 - 4750 re range.

Dave E.

phuk72 wrote:

slow codger wrote: Last time we were at Cadwell, Out of the 3 Daves 2 of us were at 96 db and Trixynut was at 99 db. That at 5000 revs, held. A GSXR 1000 failed and he was told to he couldn't run, and no sticker.

Dave E.

5,000 rpm is the ACU suggested level for twins - should be measured 1 metre behind bike and one metre from floor.

Last time mine was measured like that it 104.7

was that with the 60mm pipe or the standard 52mm akra

slow codger wrote: Well If it was supposed to be a metre............. It was nearer 2 ft as I remember. And he was so busy watching the exhaust that he didnt notice that most of us were in the 4500 - 4750 re range.

Dave E.

Just read on the MSV website that they measure from 0.5m

cheesie wrote: Last time mine was measured like that it 104.7

was that with the 60mm pipe or the standard 52mm akra[/quote]

That was with the Devil pipe - the standard Akra is relatively quiet next to mine (and I'm not joking)

Here in OZ I have never had to submit the TRX to a niose test, which is lucky as it was recently tested for a roadworthy and was rated at 107dB