IVA results

[Big Vern]

Hi Ash,

See here for convex glass mirrors and replacement glass

http://www.minispares.com/Product.aspx?ty=pb&pid=37061

Regards BV.

[dogwood]

Just called in on Ash.
We were discussing the mirrors.
Plus some other bits he failed on that others have passed with ok
Seemed strange mine and several others have passed
with the same mirrors, and his failed.
They are Yamaha R1 mirrors.
Seems they are ok for everyone but him.

[davidimurray]

Out of interest have you compared the position of yours and Ash mirrors? Wonder if Ash are slightly further back?

[dogwood]

Originally Posted by davidimurray

Out of interest have you compared the position of yours and Ash mirrors? Wonder if Ash are slightly further back?

Nope, in exactly the same place.
Ash checked on mine before fitting his.
To try and avoid this exact problem

[Big Vern]

I suspect there are several minor issues here.

IVA Inspectors are probably required to follow normal type approval techniques in conducting field of view checks which wasn't always the case with SVA. ie rotating head but torso must remain in stationary position.

Small mirrors will have a smaller field of view from any particular viewing point.

I have also conducted a test with a small make up mirror which indicates motor cycle mirrors may not be suitable - with the mirror to my left just 18" from my head and with the right side of my face on the right hand edge of the image in the mirror I can see quite a lot behind my left shoulder and to the left of this! but when I move 50" away from the mirror and try again I can see very little of what is behind my left shoulder......
I wonder if this reduces the field of vision when using motor cycle mirrors.

As for the noise issue, I'm assuming Ash didn't use an SVA compliant muffler?
The trouble with straight through mufflers if they're LOUD
but I would have thought SVA compliant mufflers would have been available for some time so being over the limit by 2db would be understandable but by 7db.hhmmm.

Does the tailpipe exit horizontally or is it angled downward?

BV.

[AshG]

well the mirrors were a fair bit bigger than the size required in the iva manual so im still not sure why i had the issue. like dave said they are in the same place as his and he passed the with the same tester at the same test station doing the same test with the same equipment. Mirror tests are the same for sva and iva. i dont know why i failed but if i fit the convex mirror glass that i acquired today the tester should be happy with the improved view.

as for the noisy exhaust I bought it off blackcab on locost builders he sold it to me because he thought it wasn't loud enough lol. what i thought about after the test was that my exhaust was actually tested with the bonnet off which i suspect slightly inflated the the reading although I think it still would have been over. i have managed to acquire a very good quality calibrated db meter off of the chairman of my flying club so will be conducting some tests later in the week with the bonnet on and off.

[Bonzo]

Hi Ash

Do you happen to know what sound weighting is used for the IVA test .. A or C

As you Know my nearest IVA centre is a 200 + mile round trip for me

Really, really don't want sound to be an issue .... I am thinking along the lines of a cheapo GBS silencer, combined with an intermediate can !!??

I can buy a lo-cost ching chong decibel meter for general guidance .... I know it will be poor quality but should give a general idea of noise levels !!

I guess aim for about 96 - 97 db & sort out the silencer propper, post IVA

I'll be OK for steering/suspension set up & have access to a rolling road for brake setup .

I would like to give my build the best chance possible & have taken into account, your recent advice .... Thank's for sharing that with us all

[Big Vern]

Hi Ash,
What type of intake system are you running? is it stock from the sierra?
Side draught webers and bike carbs will make a lot of noise so you'll definitly need the bonnet on/good air cleaner.
As you have access to a noise meter do you have a chance to rotate the angle of the exhaust outlet to see what affect that has on noise?

BV.