When I was looking for aftermarket exhausts I saw our member Klingon with Predator exhausts mounted on his Trophy which looked appealing so went on this website and saw only what you see advertised which look like the stock Trophy exhausts. I inquired twice as to the ones Klingon had mounted but received no reply, and afterwards bought my exhausts from Trident which I have been very pleased with.
I used adaptors from Trident and Silencers from Delkevic for
a system that works for me.
No dyno graphs, but it does weigh less and sounds
better over stock.
Plus if you want volume, the baffles are removeable.
There is a company in Ohio, I think, EPCO, that will custom make some. They are stainless steel. I've had a few sets, for a Victory and for a Moto Guzzi, and they are a great product. Lead time is a little long.