| The system is a Termignoni, I purchased it through JHP. The quality of the welds on the outside looks fine, it is the inside that is terrible.
I used a carbide tip with an air powered high speed grinder to clean it all up.
Had the same problem with the captive nut assemblies and used ground down nuts made to fit.
The system is definately the 57mm. My friends 54mm Termi system measures in at 53.5mm external diameter.
The issue with power seems quite simple as the bikes appear to be very sensitive to cam timing.
I have graphs with three sets of cam timing with a variance of 8rwhp (128-136hp).
The job took around 3hours total, at least one of that was making things fit.
A big thanks to Rob at MPR in Melbourne who showed me how to install the system, lent me his workshop and tools and ended up doing most of the work. | 
Threaded Mode