Can anyone help,I once heard a story about a bike engine kit going through sva with a diy emmision system on it.I amd building and nearly finished ready for sva an mk gt1,it has a yamaha 1000cc thunderace engine in it,i have made my exhaust manifold them fitted a small cat off a car,then have fitted a late type yamaha R1 end can silencer which has a cat in it also so i have 2 cats in the system,my carbs have 4 x plugged vacuum pipes for carb tuning,i beliveve you can fit 4 x adjustable fish tank vent valves into the end of the pipes,and they act like reeed valves,and open and let more air in to lean the mixture off as the revs and vacuum increase.
Has anyone got any info on this,like make and part number or name of vent valves and where i can get them from,or has anybody out there done the above succsefully,if not does anyone have a cat kit they want to sell,or hire having only used it once for your sva?

Thanks Simon

contact snoopy, he's the man for bec sva emissions, fish tank valves n things.

we dont use the fish tank valves, the key is getting the cat as close to the manifold as poss
we have an sva silencer for our cars that has a catalyst welded in right where the collector form the headers ends, this makes sure the cat gets hot enough to work ( exhaust melted sva mans probe last time )
so far this has worked on 2 x 99 r1 engines 3 x fireblade and 1 x zx9r
think the cat that i used in the system came from a 98 fiesta si 1.2 16v

hope this helps

best regards

marc

With two cats.... It will PURR very nicely

thanks for the advice guys will be taking it for mot soon so will have a chance to check it before sva,the 1st cat is about 2ft from collector,so we will have to wait and see.

cheers Simon.

I passed with a cat from a fiesta, I would agree get the system as hot as possible. I fitted air bleed valve's but didn't need to use them.