[CR] Return Spring for Simplex Rigidex RD

Example: Framebuilding:Restoration

Date: Wed, 27 May 2009 13:40:37 -0700
From: Jerome & Elizabeth Moos <jerrymoos@sbcglobal.net>
To: CR discussion list <Classicrendezvous@bikelist.org>
Subject: [CR] Return Spring for Simplex Rigidex RD

Slowing beginning to accumulate parts to build the Duravia. I bought a Simplex Rigidex 35 chainstay mounted RD, but it is missing the return spring. This was was a long spring that the eBay seller describes as a "screen-door" spring, which hooks to the RD at its rear end and to an eyelet on the chainstay at its front end, The Duravia does have such a chainstay eyelet, but I think many brands/models of RD's used a similar spring, so the frame wasn't recessarily designed for this RD. Anyone know where I might find a spring or if some generic spring from the hardware can be adapted to work?

There seem to be other very similar Simplex RD's but made for a different type of chainstay mounting bracket. Must one use a complete RD for the appropriate plate on the frame, or is the RD part which attaches to the frame one that can be changed out from one Simplex RD to another?

Also related to the Duravia, which seems to be a 1954, some have suggested that MAFAC Dural Forge brakes would be period correct. Anyone have a timeline for MAFAC brakes that might help me confirm this? What about a CLB timeline?

Finally, the rear spacing measures about 115 mm. Was this a common spacing in the 50's? If one cannot find a 115 mm hub, would it more likely work to reduce spacing on a 120mm or to space out something narrower (110 maybe)?


Jerry Moos
Big Spring, Texas, USA