111dB

is 111dB considered a bit loud for a bike exhaust? Is there any set figure
it should meet?

 

Err... yes, just a tad...

Depends on the capacity & age of the bike.
http://www.dft.gov.uk/stellent/groups/dft_roads/documents/page/dft_roads
_506856.hcsp

 

that's only at full tilt mind about a meter away from the zorst, it's around
85 db on tick over ISTR.

 

I don't know how they test it for road use. The ACU test for
competition use is a metre away at 45 degrees & 50% of max RPM iirc,
although for off-road competitions the RPM depends on the engine
capacity.

 

That's still too loud, my Bandit says 80 dBA on its exhaust.

 

define too loud. This is an afermarket home brew type thing ;-) It's got
the BSAU thingy on it though.

 

I'd take the BS thingy off if I were you - at least you won't get done
for fraud or deception or whatever it is then.

 

I don't think that matters now anyway.. the mot people are supposed to
listen to it. Granted, something that has 111 db is taking the piss just
a little.

 

Why would it be fraud or deception? Perhaps I should ask MTC exhausts to
take it out of their manufacturing process then? That's the aftermarket bit
as is the link pipe, the middle connector section rusted away so I welded
the headers direct to the link pipe so that's the home brew bit. No baflles
removed or anything like that though, I've not played with it apart from
welding the two pipes directly together.

 

111dB is only when you wang open the throttle and hold it on the red line,
tick over is much much lower.

The MOT guy said "The exhaust is a touch on the noisey side." Still passed
it though

 

Oh my car is the same volume too when you step on the loud pedal, holding it
at red line its a bit lower, but when you step on the gas it is noiseier to
start with. That's a fully road legal exhaust system that has no problems
with anything apart from old people thinking I'm speeding.. Why are cars
treated so differently to bikes?

 

Holding it the red line, I'd expect the mechanical sound to figure
heavily in that 111 db reading too.

Excellent, desired result then. I want a link pipe for my Bandit that
has a center stand bump stop on it. Then I can keep my center stand, and
have a nicer pipe.

 

I had considered getting one for my new [1] Laser K2 system, but at tickover
it's quite civilised so I don't think I'll bother. Mind you, at full chat
it's somewhat cacophenous.

[1] new, as in new to me thanks to Ebay.

--
Dan L (Oldbloke)
My bike 1996 Kawasaki ZR1100 Zephyr
M'boy's bike 2003 Honda NSR125R (Going)
Spare Bike 1990 Suzuki TS50X (Patio Ornament)
BOTAFOT #140 (KotL 2005), X-FOT#000, DIAABTCOD #26, BOMB#18 (slow)

 

I welded a plate in place on the pipe - should yours not come with one I'd
be happy to do the same for you.

 

That sounds like a plan to me. I can't have my center stand hitting my
nice alloy swing arm can i?

 

nope, you canne have that! My came with a sort of plate on but it was the
wrong size and they'd drilled out a massive great big hole which was too big
to take the stop from the old one.... so I welded in a nice stainless one


Welding is so satisfying, although when I did that one I had a short sleeve
shirt and didnt bother with gloves, I've a nice tan and some slight 'sun'
burn now :-(

 

Stainless is really nasty stuff to drill. I may have a go at making up a
stop to go onto the pipe soon, when I get my other projects out of the
way first.

Would sun block have helped I wonder?

 

should do I'd have thought.

 

Ah right, I assumed the "home brew" bit referred to the can. No problem
then if you haven't modified that.

 

Same thing happened to me recently while doing a couple of hours
welding. I got a lovely UV burn on my left inner forearm from not
wearing gauntlets or long-sleeved shirt.

Lesson learned for next time.