I'm afraid it's true - I just ran across a copy of an old magazine (Penthouse) I was published in - I used to work for Arlen Ness and had a 2 page spread of the "Ferrari Bike" in that issue.
Cracking open the April 1991 issue, page 61-62 (Article entitled "The Right Stuff") I looked back at that old photograph - and really saw the front brake for the first time...Rotor mounted to the rim, caliper running on the inside.
Most people eyes, mine included, always got stuck on the twin blowers and 4x dual throat Del' Ortos...but Arlen was running inverted forks and ZTL brakes in 1990...
No real point to this, just thought you'd like to know. ZTL patent (if there is one) could easily be knocked down as prior art.
The ZTL patent is not that vague. There are specifics to the size, orientation, mounting blocks and hardware, etc. Erik used these factors to circumvent the Buell patents (owned by HD) when he put the perimeter brake on the EBRs. For example- on the XB, the mounting boss is centered between wheel spokes. On the EBR front wheel, they are off center to one spoke. This is verified because the Buell B2 Baracuda wheel, which I once owned, looks like the EBR front wheel, but has the mounting boss centered between the spokes like the XB wheels.
If the Geek in you needs a fix . . . just dive right into the FMVSS. . . and head straight to the motorcycle portion.
A person can learn a lot.
It'll give you a heightened understanding of things like homologation and how a company, like Buell, that was producing something like 19 model variants at a time, has to think and operate.
You'll understand things like how turn signals are located and you'll know that there are no crash standards for motorcycles (Buell made their own . . . things like "slap down wheelie") for reasons that didn't require the feds making them do anything.
Google . . . "FMVSS Motorcycles" and you'll find yourself about 3 months worth of juicy reading that will clear up a LOT of things and you''' understand wha Engineers like Brankin (1313) do . . .
You'll also understand why Vetrix's petition was granted . . . . and why so many manufacturers go out of business.
II. How This Rulemaking Began—Granting Vectrix's Petition
As described in the notice of proposed rulemaking (NPRM) published in the Federal Register (68 FR 65667) on November 21, 2003, this rulemaking began with NHTSA's decision to grant a petition for rulemaking from Vectrix Corporation. We granted the petition in light of a number of petitions we received requesting temporary exemption from the rear brake location requirement of FMVSS No. 123, i.e., temporary exemptions from S5.2.1 (Table 1) of FMVSS No. 123. These petitions have come from manufacturers of scooters with automatic transmissions and handlebar-mounted brake controls, which is a common arrangement for scooters sold in Europe, Asia, and other parts of the world outside of the United States. These manufacturers wished to sell their scooters in the United States but were prevented from doing so by the requirement that motorcycles be equipped with a right foot control for the rear brake.
NHTSA then focused its discussion on the first manufacturer, Aprilia S.p.A. of Noale, Italy, to petition for a temporary exemption from S5.2.1 (Table 1) of FMVSS No. 123. For the rear brakes, Aprilia's Leonardo 150 motorcycle had a left handlebar control, not the right foot control specified in FMVSS No. 123. Aprilia petitioned to be permitted to use the left handlebar as the location for the rear brake control for the Leonardo 150. The Leonardo's 150 cc engine produces more than the five horsepower maximum permitted for motor-driven cycles, so it was not permitted to have its rear brake controlled by a lever on the left handlebar.