From http://www.ihpva.org/mailing_lists/hpv/archive/1995/v02/100/v02.n175 as of 2006/07.

From:      owner-hpv-digest
To:        hpv-digest@zippy.sonoma.edu
Reply-To:  hpv
Precedence: bulk
Subject:   hpv-digest V2 #175


hpv-digest                Wednesday, 29 March 1995      Volume 02 : 175

[...]

From: dgwilson@MIT.EDU (David Gordon Wilson )
Date: Wed, 29 Mar 1995 08:15:21 +0000
Subject: POSITECH BRAKE

Someone asked if s/he could get Positech brakes. Alas, no! The concept for these brakes was developed and patented by Brian Hanson and me, and we built many prototypes and I hawked them around to try to get them picked up by bike or brake companies. Positech, mainly Allen Armstrong, a super designer from Arlington MA, heard about the brake and we happily came to an agreement to work on the concept together. He improved on our design, patented it (generously keeping us in the picture) and made about five prototypes (additional huge cost). We tested them thoroughly - amazing performance, even on steel rims - and sent them to various companies for their tests. The brakes performed equally well in the companies' tests. No company wanted to take out a licence or to buy the brake rights. The only result was that a prominent company tried to design something to get around the patent and called it something like a double-leverage brake. Also we spent a huge amount of time and money. I used one of the prototypes for many years on my first SWB, which had a highly loaded Moulton 16x1-3/8 steel wheel, and it worked beautifully wet and dry. The hard pads we used lasted for years.

Allen has a paper on a tricycle he's designed and built in the next issue of Human Power (vol. 12 no. 1). You will see the quality of designer he is.

Dave Wilson

From: dgwilson@MIT.EDU (David Gordon Wilson )
Date: Wed, 29 Mar 1995 08:20:33 +0000
Subject: MAGURA BRAKES, PADS & STIFFENERS

I also bought a pair of Maguras for my Avatar LWB after an enthusiastic endorsement appeared here. They are great brakes. I also couldn't get stiffeners. I wanted one on my rear brakes, because they twist the small-diameter rear stays alarmingly. So apparently I shouldn't blame the store from where I bought them (also recommended here). Should I blame the store for not having any replacement brake pads? Any ideas where I can get these? Dave Wilson

End of hpv-digest V2 #175