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So I was walking down George St at lunch today and a bus pulls up near me and PSSSSHT.

I was less than 1m than the bus... so 2 questions come to mind.

a. why dont they get defected? (and this is PURELY rhetorical so dont up shit about this)

b. why can't I sue them for hurting my ear?

... anyone wanna take my case on?

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So I was walking down George St at lunch today and a bus pulls up near me and PSSSSHT.

I was less than 1m than the bus... so 2 questions come to mind.

a. why dont they get defected? (and this is PURELY rhetorical so dont up shit about this)

b. why can't I sue them for hurting my ear?

... anyone wanna take my case on?

Its public transport... the government couldnt give two shits about peoples ears if its saving them money.

EXACTLY!!!

Why can't you have a fulsikhectic megaphone BOV in ur car if it uses MAP fueling?

Standard Cop response- " 'Cause it's noise pollution, sir."

WELL WHAT ABOUT THE FKN M#$%ERF#$%ER BUSES THEN???

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Not a BOV, it's the air compressor unloading.

When the air sysyem pumps up to working pressure, about 120psi, the compressor unloads and freewheels. The noise is the air released from the pipework between the compressor and the unloader valve.

Air brake noise is the air released from the brake system when the brakes are released.

Engine brake noise ( Jacob's engine brake) is much much louder and not usually heard in cities for obvious reasons.

Proper diesels don't need BOV's as they have no throttle butterfly. Only toy stuff like the old Toyota diesels had a butterfly as a cheap way to get vacuum for the brakes.

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I thought the deisels still had something like a BOV because on the biggins trucks, Big rigs and stuff, you hear the high pitched "powwwwwww" sound between gears.

Not a whistle, not a hiss, a "powwwwww"

make sence?

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Well, diesels, turbo diesels too have no throttle, its all controlled by the injectors and not a throttle plate, so seeing as backpressure is created by a pressure difference between the manifold and turbo outlet pipe when a throttle plate closes, they dont have to worry about a pressure wave going the wrong way down the tube and belting into the blades.

Considering even most of the little 4cylinder turbo diesels seem to run a minimum of 14-15psi and trucks run about 40+psi and they dont have a BOV it seems surplus to requirements.

Theres all kinds of pnuematic assistance on big trucks and buses for all kinds of shit, not sure which shit it is making the noise I'd have to ask my dad he used to work for International.

edit- and yes in noisy environments with trucks using compression brakes, buses and noisy fuggen bikes I hardly think some noob with a noisy BOV is hardly going to kill anyone from a ruptured eardrum.

Edited by MK2
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It would all be pnuematic reliefs. Buses like trucks use air, as its inifinite in supply, so long as the compressor is filling the tanks, and there are no leaks or wankers constantly hitting the pikes for no reason.

The noise people talk about when they change gears cant really be anything, unless that certain truck has an air assisted clutch...but truckies with some ability dont use the clutch at all unless they are stopping, starting, engaging PTO and in some trucks like volvos engaging splitter for high range (not all trucks have to use the clutch for this). I work around trucks a fair bit, and i drive them around occassionally around and out of the yard. So yeh...who knows, might be some truck with mechanical issues and is making funny noises.

Edited by r33_racer
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