Probably old ground but the search facility is a bit un refined when i comes to searching for something specific.

Do the main jets provide fuel when on fast idle test at SVA?

Reason i ask is that my carbs came with 132 jets in and they were a bit gummed up and i had a spare set of mains - 140's so popped them in to get it running.

I failed my SVA running too rich at fast idle.

Would putting the 132 mains back in (cleaned of course) put me towards the right direction to lean it up a bit?

Nope. Fast idle will basically just be the idle jets....

The R1 carbs have 3 holes near the butterfly that are connected to the same place as the idle mixture screw hole. At base idle, two and a half of the holes are blocked by the butterfly, as the throttle opens a little, the other holes are exposed one by one giving more fuel at low engine revs.

A little bit of fuel comes up through the main jets but not much.

i passed sva with 144's on, it was my understanding that fast idle doesnt really use the custom needles and jets.

Thanks Guys,

I will leave it as it is then.