These are NOT the E-series White brothers product, they are a Supertrap muffler that they are calling E-series on there rebadge job.
Steve - Respectfully, you are incorrect. The only similarity they share is a belief in radial diffusion and the tuneable disc approach. I would have thought with your extensive background you would know the obvious differences between them. Since I worked for both SuperTrapp/Kerker and White Brothers for over 20 years, and now with Fuel Moto for the last 6 years, I can best shed light on the subject and facts.
In the simplest “form” – The SuperTrapp is round; the E-Series is elliptical. When I designed and patented the E-Series in 1998 while at White Brothers, this was one of many important elements incorporated to clearly differentiate the products. SuperTrapp was so impressed with the design and performance aspects of the E-Series, they started a long due diligence process negotiating the purchase of the E-Series division from us (we declined).
There have been several “rebadged” versions of the SuperTrapp; many of which I approved (CCI/Revtech, Arlen Ness, Jardine, etc.). There were also companies that incorporated the product as original and/or aftermarket equipment such as Buell, Cagiva, H-D, etc. Perhaps since you worked with the Moco as well, we dealt with many of the same staff members when they first started working with us on our XR750 & XR1000 products (SuperTrapp), in addition to our Kerker Screaming Eagle line. Even with the original E-Series, we “rebadged” them for several companies including Polaris (V92SC) and Yamaha (GYTR). But neither SuperTrapp or E-Series are “rebadged” upon themselves as they are completely different entities.
The Fuel Moto E-Series is an evolved version of my original design. Incorporating a vast amount of changes to improve on the function and performance aspects of the design.