I just failed SVA on this - there were 2 issues, one was documentary proof of engine age. Is there a link to an engine number database, or are yamaha likely to be helpful if I write to them, or would a local bike shop be able to provide it?
Have people been able to meet the requirements by adjusting standard carbs on the day or should I invest in some "fishtank valves"?
Note I was stymied a bit by brand new test kit at oldham which they were not very good at driving....
On the + side, R1, no airbox, sausage filter sticking out the top of the bonnet, MK 421 exhaust to a cat then a stock R1 can, passed the noise test at 7500rpm no bother. I was so stunned I heard myself asking " are you sure ?"... It sounded bloody loud to me but the meter said 100dB
cheers
Bob

All R1 engines are later than 98 and so mean a cat test for SVA. You shouldn't need to prove the engine's age as if you can't, you have to to a cat test anyway. Proof of age is only for 95 and earlier engines.

I only needed to adjust the carb mixtures to pass SVA - once I'd fitted a bigger cat. The idle mixture screws provide all the control at 2500 RPM and no load. I could adjust right through the lambda range with room to spare. This gave low CO readings too. My only difficulty was getting HC down, which I did, just, with a big cat.

Cheers for that - I'd like to be SURE of a pass on the retest. I saw lambda readings of 0.6 so I believe I'm way lean - the mixture screws are air bleed yes? so screw 'em in to richen the mixture?
Bob

Be careful screwing them in at all hard as the pin on the end of 2 of mine snapped off and I had to get new ones. Frustratingly you have to wind them in and then back out to know that they're all the same. Otherwise you could be rich on 1 cylinder and lean on the others, giving really bad results.

I think on the R1, the idle mixture screw flows frothy fuel - air and fuel to supplement the bit that comes out of the mains. I can't remember if you have to turn them out to make them richer or not.

Mine passed by adusting the idle mixture screws. Screwing them out will richen it. If your reading is 0.6 then you are running rich so screw them in. I was allowed to tweek mine at the test, it doesn't take much, we're talking an eigth to a quarter of a turn at a time. Also I blanked of the Air Induction System with a valve in the pipe which would allow me bleed air in if necessary. I guess you've blanked yours off if your not running the standard airbox. I also used a highflow performance CAT, which I could smell before it was hot enough to pass the test. This also resulted in melting three of the SVA man's emissions probes!

I wonder if there was something wrong with the kit then - I was seeing HC at 28ppm and CO vestigial but lambda 0.6 - does not compute........
Thanks for the info
Bob

Take your car down to a local tyre fitting and MOT type place when they're not to busy and use their exhaust gas machine. you can set up your levels there. I did and they didn't charge me.

I second that. I got mine set up by my local garage and got a printout of the readings so I knew it should pass. However it still didn't pass on the SVA man's machine, but I knew it was close so I could tweak it at the test. The garage did charge me a small fee, but then the exhaust melted their gas analyser as well.