Decibels

[Wombat]

Thanks for the link Rossco; I'll hold onto that.
It almost looks too simple - and it's far more stylish and aerodynamic than the 20lt drum full of sawdust I tried to mount on mine.

and did you see the MX doona covers and matching sheet sets on that website?!
I'll have to show my boy; it's MY birthday in June...

[Rosco400]

Theyve got some good stuff by the looks of it, I was not aware of this site until a mate came in and showed me today, now only if they sold Crusty Babes

[mboddy]

Nice on rosco, thats a clever little device if it works.  Couldnt be hard to make somthing similar.

Best that only one of us buys it and tests it first. I am sceptical.

[Nathan S]

FWIW:

FatBoy and some bloke from MA were doing the voluntary noise testing at CD5. On Saturday afternoon, they had had less than a dozen bikes front up to be tested!
The RPM tester is some funky little spiral spring thing (like a builder's tape measure) that is pressed up against the engine cases while the engine if revved - when the spring resonates, the engine is revving to the pre-set number of revs.

My YZ125C blew 100.7dB. It's a stocker with no packing in the muffler, and none of the rubber dampers between the cylinder fins (and a fair bit of piston slap...). When it was out on the track, it sounded like one of the louder bikes out there, at least among the two strokes.

Noel's 77 CR125 was quieter than the YZ, and KB's XR75 was much louder (but I can't remember the figures for either).

[Noel]

I had my 2 bikes tested
My 77' CR125, stock chamber with home made extra silencer freshly packed 99.2 Db


77 xt 500 with home made silencer combo of concentric tubes and packed straight through 97.4 Db


I then added some disc's that I had made to fit on the end and that dropped it to 90.0 Db


I was amazed at this reading drop as when reving the bike it did not sound that much quieter
but at the testing revs the Db's just fell away



cheers
Noel

[oldfart]

Tested the Drm 400 ( 4 stroker ) and it gave a reading of 98.9 which was a pass as they have to round the reading down to  ( 98 db )   you beauty

[Freakshow]

i heard only 12 of the 40 or so bikes tested passed.  that tells a story.  

I noticed one open piped duke, would have loved to see that on the gizmo, be interested to see if it pumps for water or booms be interested in what you got planned there Mr. F

[KB171]

The XR75 pumped out 112 db at 8.500 rpm

[Wombat]

Yeah bugger, I missed my opportunity to have my bike tested.
I thought the testing was an all weekend feature but when I saw Fatboy at the test spot on Sunday morning he said it was all over and done with.
So I souvenired the noise test sign and Joel signed it.

Not to worry, rules is rules and I'm sure I'll see another noise meter in due course...

[Doc]

The record on the day was 116db by some Suzuki Would have been a 125S I'm guessing as they are pretty raspy when on the pipe. The little TM ran out at 100db on the nose so I was pretty impressed with that..won't take much to get it down from there 

[OZYKTM]

The record on the day was 116db by some Suzuki Would have been a 125S I'm guessing as they are pretty raspy when on the pipe. The little TM ran out at 100db on the nose so I was pretty impressed with that..won't take much to get it down from there 

The bike that got that 116db reading was an old DR-500 with a hot dog muffler.

[Doc]

A DR500!  okay 4 smokers can wn this title!!..not a record I'd wanna challenge really 

[evo550]

Doc,
It's about the only thing those suzies will win

[090]

I was told an xr75 with what looked like a megaphone type muffler went off the scale. I took a cr480rd,a cr125ra and a cr125m. The125 breezed in at 93db and the 480 was under also. The 125m went 102 with the dg pipe.

[KB171]

Buggered if i know who that might ave been  )But it did cause Ken Smith to run out of the tent yelling to shut it down,i think they may have been interveiwing some Belgium chap, oops. :