This style of frame was also made by Runwell Cycle Co of Birmingham. In their 1939 catalogue, they describe it as "...Registered design Safety Frame", and offer it as an alternative to their standard diamond frame on their "Runwell La Grande Gent's Roadster" bicycle.
The idea is, it would appear, to achieve a lower stand-over height, thereby avoiding possible damage to the undercarriage, which is always a hazard when riding the conventional frame. This is borne out by the name of their diamond-framed model, the"Runwell Nutcracker Gent's Roadster" bicycle.*
* Not really. Sorry, Dan.
Neil Foddering Weymouth, Dorset, England
>From: "Dan Kehew" <dan.kehew@gmail.com>
>To: "Classic Rendezvous" <classicrendezvous@bikelist.org>
>Subject: [CR]Gaspipe freakshow: Oh yeah, I'm there!
>Date: Wed, 2 May 2007 18:33:57 -0700
>
>I ride some good stuff, sure, but I'll admit to having a weakness for
>bikes that ... okay, they're junk. But they're INTERESTING junk. So
>join me in gaping at the lowered-toptube Vindec frameset that just
>eased off of the UK eBay for a cool $150:
>
>Item 230122186234 or
><http://ebay.com/<blah>
>
>Delightfully inelegant. Brutally square lugs. Painful seat cluster.
>The closeup of that seatcluster also reveals something going on
>partway down the seatstays, maybe just bad paint, maybe leprosy, I
>dunno.
>
>And if anyone has a logical explanation for the top tube arrangement,
>I wanna hear it. Keep it clean, people.
>
>Dan Kehew
>Davis (They're all good bikes here. Except Magnas. And Mt. Furys.), CA USA